Third eon of the geologic timescale, last eon of the Precambrian Supereon
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In this episode, we chat with Travis Schwertfeger, Executive Chairman of Many Peaks, a junior miner focusing on adding value through cost- effective minerals exploration and discovery and who are advancing gold and copper projects in West Africa. Travis is a geologist with over 20 years of global industry experience primarily in gold and copper projects working across Australia, Africa, and South and North America. He discusses how Many Peaks formed, what they are looking to achieve in West Africa, and discusses the geology across West Africa and why it's unique about the region. KEY TAKEAWAYS Many Peaks is concentrating its efforts on mineral exploration in West Africa, particularly in Côte d'Ivoire, which is seen as a promising region for gold and copper discoveries due to its geological similarities to other prolific mining areas. The company is employing innovative exploration methods, such as auger drilling and hyperspectral imagery, to navigate the unique geological challenges of West Africa, including the presence of iron-rich layers that complicate traditional geochemical techniques. Many Peaks has three key projects in Côte d'Ivoire, with the Ferke project being the flagship. The company is building on previous exploration successes and aims to expand the known mineralization through systematic drilling. With a tight corporate structure and a current enterprise value significantly lower than comparable companies, Many Peaks presents an attractive opportunity for investors, especially with the potential for substantial re-rates following successful drill results. BEST MOMENTS "Côte d'Ivoire hosts the largest proportion of this greenstone belt. Over 30% of the Proterozoic terrain hosting gold is there, but proportionally it's seen the least amount of exploration versus those neighbouring countries." "We believe Côte d'Ivoire is quite ripe for a generation of discoveries over this coming decade." "We're implementing a lot of auger drilling just to be able to drill through that cuirass... to get into the clay saprolite where you'll see the true endowment of gold in the rock." "We have a very tight corporate structure... with a few successful drill holes, we would quite quickly see a substantial re-rate in terms of company valuation." VALUABLE RESOURCES Mail: rob@mining-international.org LinkedIn: https://www.linkedin.com/in/rob-tyson-3a26a68/ X: https://twitter.com/MiningRobTyson YouTube: https://www.youtube.com/c/DigDeepTheMiningPodcast Web: http://www.mining-international.org https://manypeaks.com.au/ https://www.linkedin.com/company/many-peaks-gold/ https://www.linkedin.com/in/travis-schwertfeger-09745927/ https://x.com/ManyPeaksASX ABOUT THE HOST Rob Tyson is the Founder and Director of Mining International Ltd, a leading global recruitment and headhunting consultancy based in the UK specialising in all areas of mining across the globe from first-world to third-world countries from Africa, Europe, the Middle East, Asia, and Australia. We source, headhunt, and discover new and top talent through a targeted approach and search methodology and have a proven track record in sourcing and positioning exceptional candidates into our clients' organisations in any mining discipline or level. Mining International provides a transparent, informative, and trusted consultancy service to our candidates and clients to help them develop their careers and business goals and objectives in this ever-changing marketplace. CONTACT METHOD rob@mining-international.org https://www.linkedin.com/in/rob-tyson-3a26a68/ Podcast Description Rob Tyson is an established recruiter in the mining and quarrying sector and decided to produce the “Dig Deep” The Mining Podcast to provide valuable and informative content around the mining industry. He has a passion and desire to promote the industry and the podcast aims to offer the mining community an insight into people's experiences and careers covering any mining discipline, giving the listeners helpful advice and guidance on industry topics.
Let's learn about upscaling LA-ICP-MS pyrite results to whole rock geochemistry data using PCA. On the way we'll hear about the life and times of an early career geochemist and some of the ins and outs of being a geochemical consultant. For this episode we read: Using whole rock and in situ pyrite chemistry to evaluate authigenic and hydrothermal controls on trace element variability in a Zn mineralized Proterozoic subbasin (Magnall et al., 2022) --- Support this podcast: https://podcasters.spotify.com/pod/show/geochemistea/support
Today, Matt Powell explains to us why he doesn't believe that making a big pile of little things is possible. He might not ever come up with any new arguments, but there's always a new level of idiocy to be found
Dr. Andrew Knoll is a professor of Natural History and Earth and Planetary Sciences at Harvard University, renowned for his research on the evolution of life and Earth's surface environments. His work, particularly focused on the Archean and Proterozoic eons, delves into paleontology, biogeochemistry, and the critical transitions in life's history, such as the rise of eukaryotic organisms and complex life forms. Additionally, Dr. Knoll explores the causes and effects of mass extinctions and the development of early microbial life. His expertise extends to astrobiology, where he contributes to Mars exploration, applying his understanding of Earth's ancient life to the search for life on other planets. Through his research and publications, Dr. Knoll plays a pivotal role in advancing our comprehension of life's intricate history on Earth and beyond.
Namibia is a country of diverse geology and mineral deposits that is also embracing the green energy transition. The diversity of critical minerals and metals and the expansion of green energy sources for mining are all exciting for the future of Namibia. Namibia is 'elephant country' in more than one way! The Society of Economic Geologists is thrilled to collaborate with our partners the Geoscience Council of Namibia and the Geological Society of Namibia to host the SEG 2024 conference in Windhoek, September 27-30. This episode explores the geology and mineral deposits, from the Proterozoic to the present and the mineral potential that exists throughout the country. We hope you will listen in and then join us in Windhoek in a few months!Anna Nguno, Deputy Director at the Geological Survey of Namibia (GSN), Ministry of Mines and Energy and co-chair of SEG 2024 introduces the episode with a conference teaser: what to expect at the conference, the main themes, technical sessions, field trips, and more. Geological Mineral and Information System - Namibia (Geological Survey of Namibia)Next Roy Miller, previous Director of the Geological Survey of Namibia, provides an overview of the regional geology and tectonic history of Namibia, including the mineral deposits and economic potential of the various belts. Paleoproterozoic basement rocks contain the 1.2 Haib porphyry deposit.Mesoproterozoic rocks in the country are divided into 3 complexes, none of which contain extensive mineralization. The Neoproterozoic to Cambrian Damara Supergroup is the most extensive succession in Namibia, contains a wealth of different types of ore deposits, and is found in three belts: 1) the Damara belt in central Namibia; 2) the Kaoko belt in the northwest; and 3) the Gariep in the southwestThe Carboniferous to Jurassic Karoo Supergroup contains thin lenses of coal and sandstone aquifers. Cretaceous continental breakup resulted in Etendeka flood basalts.At the end of the Cretaceous the region became semi-arid and the Kalahari Desert began to form. In wetter periods, the Orange River flooded and deposited diamonds from inland to the coast, 90% of which are gem quality and mined today by De Beers. From 21 million years ago, sand began to accumulate in major dune fields. Finally, Mary Barton, Principal Geoscientist at Odikwa Geoservices, talks about her introduction to the field of geology and what a day in the life of a Namibian greenfields exploration geologist looks like. She discusses above ground risks in the country (including lions and cheetahs!), the placer diamond mining industry, and what opportunities the green transition might bring to the country. Theme music is Confluence by Eastwindseastwindsmusic.com
The Kiruna Mining District, 200km north of the Arctic Circle in Sweden, is well known for the giant Kiruna Iron-Oxide-Apatite (IOA) deposit. The district has a long history of iron production extending back to the late 1800s. Less well known are the copper deposits that are spatially associated with Kiruna. New work by both researchers and explorationists is providing a better understanding of the complicated relationships in these Proterozoic rocks. A shift in mindset is allowing for new perspectives and an opportunity for discovery. We first talked to Leslie Logan, PhD candidate at Luleå University of Technology. Her study focuses on the tectonic framework of the Svecokarelian greenstone belt and uses a mineral systems approach to understand mineral occurrences in the district. The origin of the copper deposits has long been debated. Leslie's work provides new data and interpretation to understand the origins and relationship of the deposits with each other. Leslie Logan - Luleå University of TechnologyOur second guest was Marcello Imaña, Chief Geologist from Copperstone Resources to talk about the history of Viscaria Cu-Fe deposit which is immediately adjacent to the giant Kiruna IOA deposit. Mining at Viscaria was carried out from 1982 to 1997. Most recently, Copperstone Resources acquired the deposit and are aiming to be in full production again in 2026 after a very successful exploration phase. Their secret was going to an old place with new ideas. Marcello shares how they changed their mindsets staying away from models and relying on what they saw in the rocks. He believes that successful efforts at Viscaria will transform and promote the Kiruna Mining District for copper.Copperstone Resources ViscariaOur music is Confluence by Eastwinds.
WELCOME TO TAKING STOCK, IT'S A ROUND UP OF TODAY'S BUSINESS NEWS & INVESTMENT VIEWS. INDICES FTSE 100 7,425 -0.5% (down 6 days in a row) 12 MONTH HIGH: 8,014 - 16/02/2023 12 MONTH LOW: 6,826 - 13/10/2022 FTSE 250 FTSE 250 17,966 -0.54% 12 MONTH HIGH: 20,614 - 01/02/23 12 MONTH LOW: 16,611 - 12/10/2022 FTSE AIM All-Share 764 -0.37% LAST TIME IT WAS THIS LEVEL WAS 22ND APRIL 2020 12 MONTH HIGH: 934 - 15/08/2022 12 MONTH LOW: 764 - 26/06/2023 3 Top Business Stories 1. The UK Prime Minister has urged homeowners and borrowers to "hold their nerve" over rising interest rates aimed at bringing down stubborn inflation. Rishi Sunak told Sunday with Laura Kuenssberg: "I want people to be reassured that we've got to hold our nerve, stick to the plan and we will get through this." This week the Bank of England raised interest rates to a 15-year high of 5%. (Click here to read more) 2. Struggling cinema chain Cineworld has said its screens will remain open despite the company planning to file for administration in the UK. The move is part of a restructuring plan for the world's second-largest cinema chain that will see its shares being suspended. The company filed for bankruptcy protection in the US last year as it struggled with debts of $5bn. But the firm said it was still business as usual for its cinemas. (Click here to read more) 3. The prospect of a new battery factory in Northumberland has suffered a setback after the buyer of Britishvolt was raided by Australian police. Investigators went to the offices of Scale Facilitation and SaniteX, owned by Australian entrepreneur David Collard over alleged tax fraud. Recharge Industries, a subsidiary of Scale Facilitation, bought Britishvolt this year after it collapsed. (Click here to read more) WINNERS & LOSERS WINNERS 1. Wildcat Petroleum #WCAT - MOU signed re Funding Wildcat has entered into a Memorandum of Understanding (MOU) with a third party that has expressed an interest to carry out due diligence on deals that Wildcat can source from Sudan. This third party will then decide whether or not to invest directly into a deal up to an amount of US$25 million. 2. IOG PLC #IOG - Successful Blythe H2 Intervention Rupert Newall, CEO, commented: "We have successfully completed the wireline intervention at Blythe H2 well, which has now flowed at a maximum stabilised rate around 42 mmscf/d, slightly above our original 30-40 mmscf/d guidance. Production will now be managed up from 20 mmscf/d towards the maximum rate to further dewater the pipeline. The team has worked very well to identify the issue and remediate it safely and efficiently. The significant improvement in our operating team performance is also demonstrated by Blythe operating efficiency increasing from 59% in 2022 to 93% over 1H23 to date. 3. Aston Martin Lagonda #AML - Aston Martin Lagonda and Lucid Group, Inc. to enter in to strategic supply agreement to create industry-leading ultra-luxury high performance electric vehicles Under the terms of the proposed agreement, Aston Martin would issue 28,352,273 new ordinary shares to Lucid and make phased cash payments to Lucid, with the aggregate value of shares issued and cash payments totalling approximately $232m (£182m) Lucid Group would become a c. 3.7% shareholder in Aston Martin Lagonda Global Holdings plc LOSERS 1. Microsaic Systems #MSYS - DeepVerge: debtor update As announced on 18 April 2023, approximately £1.4 million of overdue trade receivables were owed by DeepVerge to the Company on that date. Following further receipt of payments and Microsaic equipment from DeepVerge, this amount has further reduced to approximately £1.35 million as at 31 May 2023. The Directors believe that, after a slower start to the year, the Company's growth plans and sales pipeline prospects offer a cautiously optimistic outlook. In the event of no further reduction in the debtor balance owed to the Company by Deepverge, which seems likely given their announcement made today, Microsaic will need to raise further working capital during Q3, 2023. 2. Premier African Minerals #PREM - Offtake and Prepayment Agreement Update Premier African Minerals provides a further update on the progress of the revision of the Offtake and Prepayment Agreement entered into between Premier and Canmax Technologies. Whilst Canmax and Premier continue to engage no amendment has been signed to date, nor will an amendment containing certain of the terms now currently proposed by Canmax, be acceptable to Premier. And a formal state of Force Majeure is now in effect. (Click here to read the RNS) 3. Cineworld Group #CINE - Chapter 11 Update The Proposed Restructuring, will involve the release of approximately $4.53 billion of the Group's funded indebtedness, the execution of a rights offering to raise gross proceeds of $800 million and the provision of $1.46 billion in new debt financing. Given the level of existing debt that is expected to be released under the Plan, the Proposed Restructuring does not provide for any recovery for holders of Cineworld's existing equity interests. Most Read RNS's 1. Premier African Minerals #PREM - Offtake and Prepayment Agreement Update 2. Deepverge #DVRG - Sale or closure of subsidiaries; share suspension The Company has been seeking to sell one or more of the principal business units with the aim of raising sufficient funds to enable the remainder of the Group to continue to trade. Despite receiving indicative offers for both the Labskin (including Skin Trust Club and Rinocloud) and Modern Water businesses, in the Board's opinion none of these offers appears likely to reach a successful conclusion on a timely basis. The Board's current expectation is that this process will result in the sale, closure or administration of all Group subsidiaries. 3. Greatland Gold #GGP - Drilling commences at Paterson South Project § Drilling has commenced at the Stingray target which is an underexplored magnetic anomaly within the Budjidowns tenement § Drilling will commence shortly at the Decka target which is a combined magnetic and conductive anomaly within Proterozoic sediments, similar to Havieron § Both targets are modelled within 250m of surface, making them shallower than Havieron
Samso Insight Episode 112 is with Anna Petts, Program Coordinator - Characterising South Australia's Cover at Geological Survey of South Australia. To many people the Gawler Craton is famous for IOCG deposits (Iron Oxide Copper Gold). The most famous mine, Olympic Dam started the rush for these giant deposits. When it was announced that there was this monster of a drill intercept, RD10 with 145m at 2.2% copper together with uranium and gold. This news created a rush like the wild west where everyone flocked to the region. Subsequent to the rush, two other famous discoveries was made and they are Prominent Hill and Carrapateena. However, it was not until 2001 when Prominent Hill was discovered and in 2005 that Carrapateena was discovered. All this action was in the eastern region of the Gawler Craton and this region was named the Olympic Metallogenic Belt or the IOCG Belt. Figure 1: The Olympic Cu-Au Province in the context of the geology of southern Australia. The main lithotectonic units of the Gawler Craton and Curnamona Province are shown and are interpreted from surface observation and geophysical data. The Olympic Cu-Au Province occurs in the eastern Gawler Craton and also indicated is the Central Gawler Gold Province, a gold-dominated metallogenic province formed during the same early Mesoproterozoic tectonic event that formed the Olympic Cu-Au Province. Inset shows the location of the Gawler Craton and Curnamona Province in the context of major Archean and Proterozoic terranes of Australia. (Source: Reid, Anthony. (2019). The Olympic Cu-Au Province, Gawler Craton: A Review of the Lithospheric Architecture, Geodynamic Setting, Alteration Systems, Cover Successions and Prospectivity. Minerals. 9. 371. 10.3390/min9060371. The complexity of the surrounding area is not for the faint hearted as they are still arguing about the origins and formation of Olympic Dam. Figure 1 gives a high level summary of the Gawler Craton and its different geological events. There is no doubt that there is no simple answer but what the mineral explorers do know very well, is that their Return On Investment (ROI) here is not high. For this reason, the Gawler remains one of the least explored regions on the Australian continent. Hence, this discussion with Anna Petts is all about the prospectivity of the Gawler and what the Geological Survey of South Australia is doing to help explorers have the edge and the resources to understand and explore the region. Gold Discovery in the Gawler Craton In 1995, there was the discovery of a gold mine in the other half of the Gawler Craton. The more "boring" part which birth the Challenger Gold Mine. This set up a rush to the area, however, till today, there is no Challenger replica. To me, this has got to be one of the mysteries of Australian mineral exploration. If you draw a radius of 100km from the Challenger Gold Mine, there is nothing that is better than a prospect to be found (Figure 2). It will be pretty safe to say that the lack of discoveries is probably due to the fact that the last 20 years of exploration has been few and far in between due to a lack of exploration funding and the historical low ROI in looking for minerals in the Gawler Craton. Figure 2: The spatial emptiness of big discoveries within the Gawler Craton. The comparison to a typical mining town like Kalgoorlie, there is too many producing assets to count.(Source: Taiton Resource Limited) Why I like the Gawler Craton My first introduction to the Gawler Craton was way back in 2019 when I looked over the Jumbuck project. Figure 2 was the result of that exercise when I was involved in trying to list a company with the project. I could see that there had not been any serious exploration in the region. The conversation that I had with people was that it is hard to make discoveries. The geophysics were not picking anything up. There were not enough data out publicly that companies could use to make discoveries. The lack of success was biting into exploration funding. Imagine a province like the Gawler Craton that still hides major discoveries. Look at the statistical probability of not finding another Challenger. This has to be a great place for the average mineral explorer who has the courage to test their exploration skill. Looking at the western province of the Gawler, the western part of the Stuart Highway, there are no producing mines currently. There are three deposits (Challenger is closed) that exist and two are currently being drilled out to see if they make the cut to become producing gold mines. In one conversation, I was told that while drilling for iron ore, they came across a Gossan. This shows the variability of the area. It was only two to three years ago that the south-western part of the Gawler was identified as a new nickel sulphide area. Samso's Conclusion So what do I make out of this conversation with Anna. What I got out of it is that there is now a flow of fata that is being made public for explorers. The understanding of the Gawler is going to take a magnitude step forward in the near future, if not already. The testing of theories are now being played out with companies such as, Indiana Resources Limited (ASX: IDA), Cobra Resources Limited PLC, Investigator Resources Limited (ASX: IVR), Petratherm Limited (ASX: PTR), Barton Gold Holdings Limited (ASX: BGD), Marmota Limited (ASX: MEU) Taiton Resources Limited (ASX: T88) The company that I am involved with is testing the concept that there is a unloved and unrecognised mineral system in between the Olympic Dam Belt and the Gawler Craton gold province, see Figure 3. The concept of a theory like this can be easily considered to be shooting with a long bow, but the recent announcement has made good evidence that there could be some truth to the madness. Figure 3: The region that Taiton Resources Limited is testing its theory that there is a mineral system in the region (Red) which is now proven to be tapping the same source as the Olympic IOCG Belt (Green). The zircon test has come back with age of 1597.8 Ma, which is atypical of Olympic Dam. (source: Taiton Resources Limited). The concept is that the red region (Figure 3) has been misinterpreted in the past and there lies a mineral system that may be fertile and endowed with mineralisation. This is the postulation and as mineral explorers, we are supposed to be testing the boundaries of believe. The role of the explorer is to come up with the ideas and the concept and of finding minerals when others have missed. The role of the Geological Survey is to provide the tools and the solutions to aid discovery. After speaking with Anna, I feel that the Geological Survey is contributing a lot at the moment. The theory for Taiton Resources came about due to the data release in around 2020. The idea was born and the money was raised to test the theory. As a director of the company and as the person who spoke to the vendor of the Highway project, David McSkimming, I will say that the theory for Highway is the best I have heard. I like the idea that there is a different thinking to understanding the mineral system in this region. What the company has done to date has proven that this theory is still valid. Not only have we proven our original story is valid, we think that we could be on the edge of two tectonic event and that would make us siting on the margin of a major structural feature. We all know that major structural features are the blessing for an exploration project. None of what I had described would not have been possible without the work generated by the Geological Survey of South Australia. Anna has clearly described what the Survey is doing and what datasets are now available. The new datasets will allow future explorers to take on what is potentially the last mineral province that has not been searched with intent for the last twenty years. Chapters: 00:00 Start 00:20 Introduction 01:51 About Anna Petts 02:24 Disclaimer 03:04 The potential at Gawler Craton 06:07 The cover at Gawler Craton 10:39 Uncovering the lack of recent significant exploration stories 16:52 The exploration government initiatives 20:05 Potential mining hotspots 25:17 Understanding the overall complex of the big discoveries 29:01 Prospectively at Gawler Craton 32:31 All about the Ultrafine+ project 44:39 Potential mining location worth looking at 46:10 Conclusion
Simon Rollason CEO of Aterian #ATN says the results that indicate the presence of sediment-hosted copper mineralisation, at the Company's recently acquired Tata Project in Morocco, is very exciting given they still have a significant strike length of over 25 km to explore and sample. Highlights: · Stratiform sediment-hosted copper mineralisation identified within Adoudounian sediments occurring on the flanks of a Proterozoic inlier. · 2.05 % Cu reported from a dolomite float sample located adjacent to the contact between Adoudounian sediments and the Proterozoic inlier. · Results include 0.95 % Cu from a 4 m thick dolomitic sequence and 0.87% Cu from an 8 m thick sequence of dolomite and marl. · 25.5 km of Adoudou Formation strike extension remains untested within the Project. · Copper mineralisation is also identified within younger units overlying the Adoudou Formation. · The Project hosts a mapped historical copper-gold and gold occurrence. · The Project is located 50 km southeast of the Tizert copper mine (mineralisation hosted at Tizert is not necessarily indicative of mineralisation at Tata). · The Company's recently acquired Moroccan projects are located in established current and historic copper and silver mining districts. · The Company holds 15 highly prospective projects in Morocco, totalling 762 km2. To read the full RNS click here
A single fertilised egg generates an embryo. Different cell types in this embryo develop into various organs of a new human being, including a new human brain. Everything starts with a single fertilised egg, and in the embryo, some embryonic cells develop into neural stem cells that construct the brain. By the time a baby is born, its brain is already made up of billions of precisely designed neurons that are connected by trillions of synapses to form a small, compact but incredibly powerful supercomputer. In his recent book “Zero to Birth: How the Human Brain Is Built” pioneering experimental neurobiologist professor William Harris takes the reader on an incredible journey to the very edge of creation, from the moment an egg is fertilised to every stage of a human brain's development in the womb — and even a bit beyond. In this episode of Bridging the Gaps, I speak with Professor William Harris the process of how the brain is built. William Harris is professor emeritus of anatomy at the University of Cambridge. He is the coauthor of Development of the Nervous System and Genetic Neurobiology and the co-editor of Retinal Development. He is a fellow of the Royal Society. We begin by examining the evolutionary history of the brain, which spans billions of years and in the Proterozoic eon, when multicellular animals first descended from single-celled organisms, and then we discuss how the development of a fetal brain over the course of nine months reflects the brain's evolution through the ages. We discuss the emergence of first neural stem cells and how the formation of the neural plate and then its progress to the neural tube give the first glimpses of the development of the brain in an embryo. We discuss in detail how cells divide and create neural stem cells and then how these stem cells start producing neurons. A fascinating topic that we then cover is how individual neurons form connections with other neurons. Professor Harris explains how comparative animal studies have been crucial to understanding what makes a human brain human, and how advances in science are assisting us in understanding many qualities that don't manifest until later in life. This has been a fascinating discussion on an intriguing topic. Complement this discussion with “The Spike: Journey of Electric Signals in Brain from Perception to Action with Professor Mark Humphries” available at: https://www.bridgingthegaps.ie/2021/06/the-spike-journey-of-electric-signals-in-brain-from-perception-to-action-with-professor-mark-humphries/ And then listen to “The Self-Assembling Brain” and the Quest for Artificial General Intelligence with Professor Peter Robin Hiesinger available at: https://www.bridgingthegaps.ie/2021/11/the-self-assembling-brain-and-the-quest-for-artificial-general-intelligence-with-professor-peter-robin-hiesinger/
The line from Brazil had some connection issues, so apologies for the poor sound quality in places.Altamira Gold Corp. is a Canada-based junior natural resource company. The Company is principally engaged in the acquisition, exploration, development and mining of mineral properties. The Company's Cajueiro Project comprises a land package of approximately 28,557 hectares (ha) and is located in the Alta Floresta Gold Belt, a Proterozoic calc-alkaline volcanic arc, which includes the metamorphic crustal segments. Its Apiacas Project is located approximately 50 kilometers (km) west of Cajueiro Project within the Alta Floresta Belt, which is approximately 82,000 ha land package. Its Santa Helena Project is located approximately 60 km south west of Anglo American's porphyry copper discovery at Jaca. Its Porta Aberta Project area is located approximately 13 km SSW of the Cajueiro Project. Its other projects include Colider, Nova Canaa and Vila Rica, among others.
We often use the phrase ‘it's the end of an era' to signify some great change in our lives, like leaving school forever. But actual eras are far, far longer than our brains can comprehend, usually lasting several hundred million years, with dramatic, global ecological changes as their finale. Around 541 million years ago, there was such an ending. As the Neoproterozoic era came to a close, so did the Proterozoic eon, and nearly 3.5 billion years of bacterial rule. Suddenly the prokaryotic mats were breaking apart and the slow, soft-bodied organisms that characterised the late Neoproterozoic were dying. Following this mass extinction, the new Cambrian period brought stunning increases in the diversity and complexity of life. These increases are called the Cambrian explosion. But what caused such a striking shift?This episode I will start with the fundamentals and work our way to the theorised explanations for the Cambrian explosion. I'll explain how evolution works, summarise the great history of life on Earth, and outline the methods that scientists use to examine this history. Then I'll draw our attention to the border between Ediacaran and Cambrian periods. We will see what was so significant about the evolutionary changes there, before assessing some of the most plausible reasons why the Cambrian explosion happened, and why it happened then of all times. https://whatwedontknow.buzzsprout.com/
Ethan Panner the rockmanethan on all social medias, Binghamton University master student specializing in tectonic geomorphology.check out Ethan Tik Tok as he cracks open rock that have not seen the light of day in millions of years.Ethan Tik Tok https://vm.tiktok.com/TTPdrX2PB3/Linktr.eehttps://linktr.ee/ethpenSubscribe YouTube https://www.youtube.com/channel/UCb-X7wvMYSyywC1X3kUjHUAR2 Cents Instagram https://www.instagram.com/r2_cents/R2 cents Twitterhttps://twitter.com/r2_cents_R2 Cents Tik Tokhttps://vm.tiktok.com/ZMe4GkPev/R2 Cents reddithttps://www.reddit.com/u/r2_oscar_mike_cents?utm_medium=android_app&utm_source=share Produced by: Oscar CRBuzzsprout - Let's get your podcast launched! Start for FREEDisclaimer: This post contains affiliate links. If you make a purchase, I may receive a commission at no extra cost to you.
Willeson Metals is a Canadian-based, privately-owned mineral exploration company focused on the acquisition, exploration, and development of high-quality gold projects in the province of Manitoba, with a particular emphasis on Proterozoic terrains, which have long been under-explored in Canada for gold. The company's portfolio of four, 100%-owned, gold projects are all located within the Proterozoic Lynn Lake greenstone belt of northern Manitoba.Willeson Metals' vision is to explore for and discover Tier 1 gold deposits in the Proterozoic terrains of Canada and to do so in a responsible, safe and sustainable manner in order to create long-term value for all stakeholders.
Placer Gold Puzzles starts with the Witwatersrand, South Africa and the long debate over the model for gold formation. After that, we head to Brazil to see how quality geochemical data analysis assisted by machine learning helped decipher a Proterozoic paleo placer. Lastly we consider changing mindsets about legacy mining through a new model that aims to create net benefit from the mining of placer gold. Professor Hartwig Frimmel (University of Wuerzburg) takes us through the history and the science of ore deposit models for the Witwatersrand, providing insights into what makes our work relevant and how do we can do our best work. From the Archaean in South Africa we go to Tristar Gold's Castelo de Sonhos Project to find out how Britt Bluemel (Goldspot Discoveries) used geochemical analysis of large data sets helped create a geologic model for exploration. We finish up with Stephen D'Esposito (President and CEO of Resolve NGO). Steve spearheaded, Salmon Gold, a new venture that works with placer gold miners to rehabilitate streams in Alaska, the Yukon and British Columbia. Can we do more than just the minimum and create net-benefit for biodiversity? He suggests a change in mindset, where we start looking at legacy of mining as an opportunity.Theme music is Confluence by Eastwindseastwindsmusic.com
Dr Daniel Mills is a Post-Doc at Stanford University. His research primarily concerns the co-evolution of the Proterozoic biosphere (Earth's ‘middle age,' 2.5-0.541 billion years ago) and eukaryotic life — a topic he approaches by studying modern organisms and environments.As we chat, we give credence to the discoveries of Vladimir Vernadsky, a Russian mineralogist who, in the early 20th century published a book called The Biosphere. Vernadsky realised that the geology, chemistry and biology on earth are intricately intertwined. They influence each other. His ideas were a precursor to the Gaia hypothesis, that the earth is a living breathing entity. Her systems work to bring balance via geological and biological processes.Visit Dan at:https://www.danielbradymills.com/context See acast.com/privacy for privacy and opt-out information.
This week we are joined by Dr Peter Crockford from Princeton University and the Weizmann Institute of Science. Peter is the author of 'Triple oxygen isotope evidence for limited mid-Proterozoic primary productivity'. Join us to discover more about the earth's biosphere 1.5 billion years ago. What evidence is there for fluctuating oxygen levels 2.5 billion years ago? How have computing techniques evolved over time? What is it like to work in two academic institutes? In this episode, Peter answers all of these questions and more.We will also gain further insights into 'Triple oxygen isotope evidence for limited mid-Proterozoic primary productivity', its impacts and the motivation behind Peter's work.In today's episode, we discuss:Peter describes his academic background and the paper in question. [01:00]We are guided through the Monte Carlo sampling methodology. [03:45]Peter tells us how oxygen isotopes created life on earth. [08:51]What is life like working in two different academic institutions? [13:22]What topics are hot in the field? [15:21]Finally, Peter gives us his tips to increase academic output alongside his one piece of advice for anyone undertaking a PhD. [16:36]Read the article here!This podcast is brought to you by RESEARCHER, the free app that makes it easy for academics and scientists to stay on top of new research in their area. Download it for free on iOS, Android or find us on your browser at www.researcherapp.io. See acast.com/privacy for privacy and opt-out information.
Raymond Pierrehumbert, holder of the Halley Professorship of Physics at Oxford, gives the 2017 annual Wolfson Haldane Lecture. The lecture is introduced by Hermione Lee, College President. The Proterozoic is the period of Earth history extending from approximately 2.5 billion years ago to 550 million years ago, and makes up something over half of all Earth history to date. It begins with a dramatic rise in oxygen in the atmosphere, global “snowball” glaciations, and major disturbances of the carbon cycle, and ends with another period of carbon cycle fluctuations accompanied by the two Snowball glaciations; shortly after the exit from the second of these, the first multicellular life appears in the fossil record, and not long thereafter comes the Cambrian explosion. However, between the two eras of great climate disruption extends a period of about a billion years in which nothing much is happening, either from the standpoint of evolutionary innovation (insofar as visible for single-celled life in the fossil record) or from the standpoint of glaciation or biogeochemical cycling. This is the “boring billion” — the geological waiting room for the modern era of the Phanerozoic leading to the appearance of intelligent life on Earth. But what was the pacemaker determining the exit from the Boring Billion? Were we unlucky in the duration of the wait? Were we just lucky, and could it have been the Boring Two Billion? That would have in fact precluded the emergence of complex life on Earth, or any other planet orbiting a star like the Sun, since the gradual brightening of a Sunlike star over time throws an Earthlike planet into a runaway greenhouse state after about 4.5 billion years (roughly a half billion years from now), whereafter the planet loses its oceans and turns into an uninhabitable Venus-like world. Thus, the nature of the Boring Billion, and the factors that terminated it, have a very great bearing on whether we are alone in the universe. Dim red dwarf stars, which age more slowly than Sunlike stars, are known to have planets and perhaps offer more chances for complex life to emerge, but have their own challenges, which will also be discussed in this lecture.
The Marine-Life Era on Urantia (672.1) 59:0.1 WE RECKON the history of Urantia as beginning about one billion years ago and extending through five major eras: (672.2) 59:0.2 1. The prelife era extends over the initial four hundred and fifty million years, from about the time the planet attained its present size to the time of life establishment. Your students have designated this period as the Archeozoic. (672.3) 59:0.3 2. The life-dawn era extends over the next one hundred and fifty million years. This epoch intervenes between the preceding prelife or cataclysmic age and the following period of more highly developed marine life. This era is known to your researchers as the Proterozoic. (672.4) 59:0.4 3. The marine-life era covers the next two hundred and fifty million years and is best known to you as the Paleozoic. (672.5) 59:0.5 4. The early land-life era extends over the next one hundred million years and is known as the Mesozoic. (672.6) 59:0.6 5. The mammalian era occupies the last fifty million years. This recent-times era is known as the Cenozoic. (672.7) 59:0.7 The marine-life era thus covers about one quarter of your planetary history. It may be subdivided into six long periods, each characterized by certain well-defined developments in both the geologic realms and the biologic domains. (672.8) 59:0.8 As this era begins, the sea bottoms, the extensive continental shelves, and the numerous shallow near-shore basins are covered with prolific vegetation. The more simple and primitive forms of animal life have already developed from preceding vegetable organisms, and the early animal organisms have gradually made their way along the extensive coast lines of the various land masses until the many inland seas are teeming with primitive marine life. Since so few of these early organisms had shells, not many have been preserved as fossils. Nevertheless the stage is set for the opening chapters of that great “stone book” of the life-record preservation which was so methodically laid down during the succeeding ages. (672.9) 59:0.9 The continent of North America is wonderfully rich in the fossil-bearing deposits of the entire marine-life era. The very first and oldest layers are separated from the later strata of the preceding period by extensive erosion deposits which clearly segregate these two stages of planetary development. 1. Early Marine Life in the Shallow Seas The Trilobite Age (673.1) 59:1.1 By the dawn of this period of relative quiet on the earth’s surface, life is confined to the various inland seas and the oceanic shore line; as yet no form of land organism has evolved. Primitive marine animals are well established and are prepared for the next evolutionary development. Amebas are typical survivors of this initial stage of animal life, having made their appearance toward the close of the preceding transition period.* (673.2) 59:1.2 400,000,000 years ago marine life, both vegetable and animal, is fairly well distributed over the whole world. The world climate grows slightly warmer and becomes more equable. There is a general inundation of the seashores of the various continents, particularly of North and South America. New oceans appear, and the older bodies of water are greatly enlarged. (673.3) 59:1.3 Vegetation now for the first time crawls out upon the land and soon makes considerable progress in adaptation to a nonmarine habitat. (673.4) 59:1.4 Suddenly and without gradation ancestry the first multicellular animals make their appearance. The trilobites have evolved, and for ages they dominate the seas. From the standpoint of marine life this is the trilobite age. (673.5) 59:1.5 In the later portion of this time segment much of North America and Europe emerged from the sea. The crust of the earth was temporarily stabilized; mountains, or rather high elevations of land, rose along the Atlantic and Pacific coasts, over the West Indies, and in southern Europe. The entire Caribbean region was highly elevated. (673.6) 59:1.6 390,000,000 years ago the land was still elevated. Over parts of eastern and western America and western Europe may be found the stone strata laid down during these times, and these are the oldest rocks which contain trilobite fossils. There were many long fingerlike gulfs projecting into the land masses in which were deposited these fossil-bearing rocks. (673.7) 59:1.7 Within a few million years the Pacific Ocean began to invade the American continents. The sinking of the land was principally due to crustal adjustment, although the lateral land spread, or continental creep, was also a factor. (673.8) 59:1.8 380,000,000 years ago Asia was subsiding, and all other continents were experiencing a short-lived emergence. But as this epoch progressed, the newly appearing Atlantic Ocean made extensive inroads on all adjacent coast lines. The northern Atlantic or Arctic seas were then connected with the southern Gulf waters. When this southern sea entered the Appalachian trough, its waves broke upon the east against mountains as high as the Alps, but in general the continents were uninteresting lowlands, utterly devoid of scenic beauty. (673.9) 59:1.9 The sedimentary deposits of these ages are of four sorts: (673.10) 59:1.10 1. Conglomerates — matter deposited near the shore lines. (673.11) 59:1.11 2. Sandstones — deposits made in shallow water but where the waves were sufficient to prevent mud settling. (673.12) 59:1.12 3. Shales — deposits made in the deeper and more quiet water. (673.13) 59:1.13 4. Limestone — including the deposits of trilobite shells in deep water. (673.14) 59:1.14 The trilobite fossils of these times present certain basic uniformities coupled with certain well-marked variations. The early animals developing from the three original life implantations were characteristic; those appearing in the Western Hemisphere were slightly different from those of the Eurasian group and from the Australasian or Australian-Antarctic type. (674.1) 59:1.15 370,000,000 years ago the great and almost total submergence of North and South America occurred, followed by the sinking of Africa and Australia. Only certain parts of North America remained above these shallow Cambrian seas. Five million years later the seas were retreating before the rising land. And all of these phenomena of land sinking and land rising were undramatic, taking place slowly over millions of years. (674.2) 59:1.16 The trilobite fossil-bearing strata of this epoch outcrop here and there throughout all the continents except in central Asia. In many regions these rocks are horizontal, but in the mountains they are tilted and distorted because of pressure and folding. And such pressure has, in many places, changed the original character of these deposits. Sandstone has been turned into quartz, shale has been changed to slate, while limestone has been converted into marble. (674.3) 59:1.17 360,000,000 years ago the land was still rising. North and South America were well up. Western Europe and the British Isles were emerging, except parts of Wales, which were deeply submerged. There were no great ice sheets during these ages. The supposed glacial deposits appearing in connection with these strata in Europe, Africa, China, and Australia are due to isolated mountain glaciers or to the displacement of glacial debris of later origin. The world climate was oceanic, not continental. The southern seas were warmer then than now, and they extended northward over North America up to the polar regions. The Gulf Stream coursed over the central portion of North America, being deflected eastward to bathe and warm the shores of Greenland, making that now ice-mantled continent a veritable tropic paradise.* (674.4) 59:1.18 The marine life was much alike the world over and consisted of the seaweeds, one-celled organisms, simple sponges, trilobites, and other crustaceans — shrimps, crabs, and lobsters. Three thousand varieties of brachiopods appeared at the close of this period, only two hundred of which have survived. These animals represent a variety of early life which has come down to the present time practically unchanged. (674.5) 59:1.19 But the trilobites were the dominant living creatures. They were sexed animals and existed in many forms; being poor swimmers, they sluggishly floated in the water or crawled along the sea bottoms, curling up in self-protection when attacked by their later appearing enemies. They grew in length from two inches to one foot and developed into four distinct groups: carnivorous, herbivorous, omnivorous, and “mud eaters.” The ability of the latter group largely to subsist on inorganic matter — being the last multicelled animal that could — explains their great increase and long survival. (674.6) 59:1.20 This was the biogeologic picture of Urantia at the end of that long period of the world’s history, embracing fifty million years, designated by your geologists as the Cambrian. 2. The First Continental Flood Stage The Invertebrate-Animal Age (674.7) 59:2.1 The periodic phenomena of land elevation and land sinking characteristic of these times were all gradual and nonspectacular, being accompanied by little or no volcanic action. Throughout all of these successive land elevations and depressions the Asiatic mother continent did not fully share the history of the other land bodies. It experienced many inundations, dipping first in one direction and then another, more particularly in its earlier history, but it does not present the uniform rock deposits which may be discovered on the other continents. In recent ages Asia has been the most stable of all the land masses. (675.1) 59:2.2 350,000,000 years ago saw the beginning of the great flood period of all the continents except central Asia. The land masses were repeatedly covered with water; only the coastal highlands remained above these shallow but widespread oscillatory inland seas. Three major inundations characterized this period, but before it ended, the continents again arose, the total land emergence being fifteen per cent greater than now exists. The Caribbean region was highly elevated. This period is not well marked off in Europe because the land fluctuations were less, while the volcanic action was more persistent. (675.2) 59:2.3 340,000,000 years ago there occurred another extensive land sinking except in Asia and Australia. The waters of the world’s oceans were generally commingled. This was a great limestone age, much of its stone being laid down by lime-secreting algae. (675.3) 59:2.4 A few million years later large portions of the American continents and Europe began to emerge from the water. In the Western Hemisphere only an arm of the Pacific Ocean remained over Mexico and the present Rocky Mountain regions, but near the close of this epoch the Atlantic and Pacific coasts again began to sink. (675.4) 59:2.5 330,000,000 years ago marks the beginning of a time sector of comparative quiet all over the world, with much land again above water. The only exception to this reign of terrestrial quiet was the eruption of the great North American volcano of eastern Kentucky, one of the greatest single volcanic activities the world has ever known. The ashes of this volcano covered five hundred square miles to a depth of from fifteen to twenty feet. (675.5) 59:2.6 320,000,000 years ago the third major flood of this period occurred. The waters of this inundation covered all the land submerged by the preceding deluge, while extending farther in many directions all over the Americas and Europe. Eastern North America and western Europe were from 10,000 to 15,000 feet under water. (675.6) 59:2.7 310,000,000 years ago the land masses of the world were again well up excepting the southern parts of North America. Mexico emerged, thus creating the Gulf Sea, which has ever since maintained its identity. (675.7) 59:2.8 The life of this period continues to evolve. The world is once again quiet and relatively peaceful; the climate remains mild and equable; the land plants are migrating farther and farther from the seashores. The life patterns are well developed, although few plant fossils of these times are to be found. (675.8) 59:2.9 This was the great age of individual animal organismal evolution, though many of the basic changes, such as the transition from plant to animal, had previously occurred. The marine fauna developed to the point where every type of life below the vertebrate scale was represented in the fossils of those rocks which were laid down during these times. But all of these animals were marine organisms. No land animals had yet appeared except a few types of worms which burrowed along the seashores, nor had the land plants yet overspread the continents; there was still too much carbon dioxide in the air to permit of the existence of air breathers. Primarily, all animals except certain of the more primitive ones are directly or indirectly dependent on plant life for their existence. (676.1) 59:2.10 The trilobites were still prominent. These little animals existed in tens of thousands of patterns and were the predecessors of modern crustaceans. Some of the trilobites had from twenty-five to four thousand tiny eyelets; others had aborted eyes. As this period closed, the trilobites shared domination of the seas with several other forms of invertebrate life. But they utterly perished during the beginning of the next period. (676.2) 59:2.11 Lime-secreting algae were widespread. There existed thousands of species of the early ancestors of the corals. Sea worms were abundant, and there were many varieties of jellyfish which have since become extinct. Corals and the later types of sponges evolved. The cephalopods were well developed, and they have survived as the modern pearly nautilus, octopus, cuttlefish, and squid. (676.3) 59:2.12 There were many varieties of shell animals, but their shells were not then so much needed for defensive purposes as in subsequent ages. The gastropods were present in the waters of the ancient seas, and they included single-shelled drills, periwinkles, and snails. The bivalve gastropods have come on down through the intervening millions of years much as they then existed and embrace the mussels, clams, oysters, and scallops. The valve-shelled organisms also evolved, and these brachiopods lived in those ancient waters much as they exist today; they even had hinged, notched, and other sorts of protective arrangements of their valves.* (676.4) 59:2.13 So ends the evolutionary story of the second great period of marine life, which is known to your geologists as the Ordovician. 3. The Second Great Flood Stage The Coral Period — The Brachiopod Age (676.5) 59:3.1 300,000,000 years ago another great period of land submergence began. The southward and northward encroachment of the ancient Silurian seas made ready to engulf most of Europe and North America. The land was not elevated far above the sea so that not much deposition occurred about the shore lines. The seas teemed with lime-shelled life, and the falling of these shells to the sea bottom gradually built up very thick layers of limestone. This is the first widespread limestone deposit, and it covers practically all of Europe and North America but only appears at the earth’s surface in a few places. The thickness of this ancient rock layer averages about one thousand feet, but many of these deposits have since been greatly deformed by tilting, upheavals, and faulting, and many have been changed to quartz, shale, and marble. (676.6) 59:3.2 No fire rocks or lava are found in the stone layers of this period except those of the great volcanoes of southern Europe and eastern Maine and the lava flows of Quebec. Volcanic action was largely past. This was the height of great water deposition; there was little or no mountain building. (676.7) 59:3.3 290,000,000 years ago the sea had largely withdrawn from the continents, and the bottoms of the surrounding oceans were sinking. The land masses were little changed until they were again submerged. The early mountain movements of all the continents were beginning, and the greatest of these crustal upheavals were the Himalayas of Asia and the great Caledonian Mountains, extending from Ireland through Scotland and on to Spitzbergen. (677.1) 59:3.4 It is in the deposits of this age that much of the gas, oil, zinc, and lead are found, the gas and oil being derived from the enormous collections of vegetable and animal matter carried down at the time of the previous land submergence, while the mineral deposits represent the sedimentation of sluggish bodies of water. Many of the rock salt deposits belong to this period. (677.2) 59:3.5 The trilobites rapidly declined, and the center of the stage was occupied by the larger mollusks, or cephalopods. These animals grew to be fifteen feet long and one foot in diameter and became masters of the seas. This species of animal appeared suddenly and assumed dominance of sea life. (677.3) 59:3.6 The great volcanic activity of this age was in the European sector. Not in millions upon millions of years had such violent and extensive volcanic eruptions occurred as now took place around the Mediterranean trough and especially in the neighborhood of the British Isles. This lava flow over the British Isles region today appears as alternate layers of lava and rock 25,000 feet thick. These rocks were laid down by the intermittent lava flows which spread out over a shallow sea bed, thus interspersing the rock deposits, and all of this was subsequently elevated high above the sea. Violent earthquakes took place in northern Europe, notably in Scotland. (677.4) 59:3.7 The oceanic climate remained mild and uniform, and the warm seas bathed the shores of the polar lands. Brachiopod and other marine-life fossils may be found in these deposits right up to the North Pole. Gastropods, brachiopods, sponges, and reef-making corals continued to increase. (677.5) 59:3.8 The close of this epoch witnesses the second advance of the Silurian seas with another commingling of the waters of the southern and northern oceans. The cephalopods dominate marine life, while associated forms of life progressively develop and differentiate. (677.6) 59:3.9 280,000,000 years ago the continents had largely emerged from the second Silurian inundation. The rock deposits of this submergence are known in North America as Niagara limestone because this is the stratum of rock over which Niagara Falls now flows. This layer of rock extends from the eastern mountains to the Mississippi valley region but not farther west except to the south. Several layers extend over Canada, portions of South America, Australia, and most of Europe, the average thickness of this Niagara series being about six hundred feet. Immediately overlying the Niagara deposit, in many regions may be found a collection of conglomerate, shale, and rock salt. This is the accumulation of secondary subsidences. This salt settled in great lagoons which were alternately opened up to the sea and then cut off so that evaporation occurred with deposition of salt along with other matter held in solution. In some regions these rock salt beds are seventy feet thick. (677.7) 59:3.10 The climate is even and mild, and marine fossils are laid down in the arctic regions. But by the end of this epoch the seas are so excessively salty that little life survives. (677.8) 59:3.11 Toward the close of the final Silurian submergence there is a great increase in the echinoderms — the stone lilies — as is evidenced by the crinoid limestone deposits. The trilobites have nearly disappeared, and the mollusks continue monarchs of the seas; coral-reef formation increases greatly. During this age, in the more favorable locations the primitive water scorpions first evolve. Soon thereafter, and suddenly, the true scorpions — actual air breathers — make their appearance. (678.1) 59:3.12 These developments terminate the third marine-life period, covering twenty-five million years and known to your researchers as the Silurian. 4. The Great Land-Emergence Stage The Vegetative Land-Life Period The Age of Fishes (678.2) 59:4.1 In the agelong struggle between land and water, for long periods the sea has been comparatively victorious, but times of land victory are just ahead. And the continental drifts have not proceeded so far but that, at times, practically all of the land of the world is connected by slender isthmuses and narrow land bridges. (678.3) 59:4.2 As the land emerges from the last Silurian inundation, an important period in world development and life evolution comes to an end. It is the dawn of a new age on earth. The naked and unattractive landscape of former times is becoming clothed with luxuriant verdure, and the first magnificent forests will soon appear. (678.4) 59:4.3 The marine life of this age was very diverse due to the early species segregation, but later on there was free commingling and association of all these different types. The brachiopods early reached their climax, being succeeded by the arthropods, and barnacles made their first appearance. But the greatest event of all was the sudden appearance of the fish family. This became the age of fishes, that period of the world’s history characterized by the vertebrate type of animal. (678.5) 59:4.4 270,000,000 years ago the continents were all above water. In millions upon millions of years not so much land had been above water at one time; it was one of the greatest land-emergence epochs in all world history. (678.6) 59:4.5 Five million years later the land areas of North and South America, Europe, Africa, northern Asia, and Australia were briefly inundated, in North America the submergence at one time or another being almost complete; and the resulting limestone layers run from 500 to 5,000 feet in thickness. These various Devonian seas extended first in one direction and then in another so that the immense arctic North American inland sea found an outlet to the Pacific Ocean through northern California. (678.7) 59:4.6 260,000,000 years ago, toward the end of this land-depression epoch, North America was partially overspread by seas having simultaneous connection with the Pacific, Atlantic, Arctic, and Gulf waters. The deposits of these later stages of the first Devonian flood average about one thousand feet in thickness. The coral reefs characterizing these times indicate that the inland seas were clear and shallow. Such coral deposits are exposed in the banks of the Ohio River near Louisville, Kentucky, and are about one hundred feet thick, embracing more than two hundred varieties. These coral formations extend through Canada and northern Europe to the arctic regions. (678.8) 59:4.7 Following these submergences, many of the shore lines were considerably elevated so that the earlier deposits were covered by mud or shale. There is also a red sandstone stratum which characterizes one of the Devonian sedimentations, and this red layer extends over much of the earth’s surface, being found in North and South America, Europe, Russia, China, Africa, and Australia. Such red deposits are suggestive of arid or semiarid conditions, but the climate of this epoch was still mild and even. (679.1) 59:4.8 Throughout all of this period the land southeast of the Cincinnati Island remained well above water. But very much of western Europe, including the British Isles, was submerged. In Wales, Germany, and other places in Europe the Devonian rocks are 20,000 feet thick. (679.2) 59:4.9 250,000,000 years ago witnessed the appearance of the fish family, the vertebrates, one of the most important steps in all prehuman evolution. (679.3) 59:4.10 The arthropods, or crustaceans, were the ancestors of the first vertebrates. The forerunners of the fish family were two modified arthropod ancestors; one had a long body connecting a head and tail, while the other was a backboneless, jawless prefish. But these preliminary types were quickly destroyed when the fishes, the first vertebrates of the animal world, made their sudden appearance from the north. (679.4) 59:4.11 Many of the largest true fish belong to this age, some of the teeth-bearing varieties being twenty-five to thirty feet long; the present-day sharks are the survivors of these ancient fishes. The lung and armored fishes reached their evolutionary apex, and before this epoch had ended, fishes had adapted to both fresh and salt waters. (679.5) 59:4.12 Veritable bone beds of fish teeth and skeletons may be found in the deposits laid down toward the close of this period, and rich fossil beds are situated along the coast of California since many sheltered bays of the Pacific Ocean extended into the land of that region. (679.6) 59:4.13 The earth was being rapidly overrun by the new orders of land vegetation. Heretofore few plants grew on land except about the water’s edge. Now, and suddenly, the prolific fern family appeared and quickly spread over the face of the rapidly rising land in all parts of the world. Tree types, two feet thick and forty feet high, soon developed; later on, leaves evolved, but these early varieties had only rudimentary foliage. There were many smaller plants, but their fossils are not found since they were usually destroyed by the still earlier appearing bacteria. (679.7) 59:4.14 As the land rose, North America became connected with Europe by land bridges extending to Greenland. And today Greenland holds the remains of these early land plants beneath its mantle of ice. (679.8) 59:4.15 240,000,000 years ago the land over parts of both Europe and North and South America began to sink. This subsidence marked the appearance of the last and least extensive of the Devonian floods. The arctic seas again moved southward over much of North America, the Atlantic inundated a large part of Europe and western Asia, while the southern Pacific covered most of India. This inundation was slow in appearing and equally slow in retreating. The Catskill Mountains along the west bank of the Hudson River are one of the largest geologic monuments of this epoch to be found on the surface of North America. (679.9) 59:4.16 230,000,000 years ago the seas were continuing their retreat. Much of North America was above water, and great volcanic activity occurred in the St. Lawrence region. Mount Royal, at Montreal, is the eroded neck of one of these volcanoes. The deposits of this entire epoch are well shown in the Appalachian Mountains of North America where the Susquehanna River has cut a valley exposing these successive layers, which attained a thickness of over 13,000 feet. (680.1) 59:4.17 The elevation of the continents proceeded, and the atmosphere was becoming enriched with oxygen. The earth was overspread by vast forests of ferns one hundred feet high and by the peculiar trees of those days, silent forests; not a sound was heard, not even the rustle of a leaf, for such trees had no leaves. (680.2) 59:4.18 And thus drew to a close one of the longest periods of marine-life evolution, the age of fishes. This period of the world’s history lasted almost fifty million years; it has become known to your researchers as the Devonian. 5. The Crustal-Shifting Stage The Fern-Forest Carboniferous Period The Age of Frogs (680.3) 59:5.1 The appearance of fish during the preceding period marks the apex of marine-life evolution. From this point onward the evolution of land life becomes increasingly important. And this period opens with the stage almost ideally set for the appearance of the first land animals. (680.4) 59:5.2 220,000,000 years ago many of the continental land areas, including most of North America, were above water. The land was overrun by luxurious vegetation; this was indeed the age of ferns. Carbon dioxide was still present in the atmosphere but in lessening degree. (680.5) 59:5.3 Shortly thereafter the central portion of North America was inundated, creating two great inland seas. Both the Atlantic and Pacific coastal highlands were situated just beyond the present shore lines. These two seas presently united, commingling their different forms of life, and the union of these marine fauna marked the beginning of the rapid and world-wide decline in marine life and the opening of the subsequent land-life period. (680.6) 59:5.4 210,000,000 years ago the warm-water arctic seas covered most of North America and Europe. The south polar waters inundated South America and Australia, while both Africa and Asia were highly elevated. (680.7) 59:5.5 When the seas were at their height, a new evolutionary development suddenly occurred. Abruptly, the first of the land animals appeared. There were numerous species of these animals that were able to live on land or in water. These air-breathing amphibians developed from the arthropods, whose swim bladders had evolved into lungs. (680.8) 59:5.6 From the briny waters of the seas there crawled out upon the land snails, scorpions, and frogs. Today frogs still lay their eggs in water, and their young first exist as little fishes, tadpoles. This period could well be known as the age of frogs. (680.9) 59:5.7 Very soon thereafter the insects first appeared and, together with spiders, scorpions, cockroaches, crickets, and locusts, soon overspread the continents of the world. Dragon flies measured thirty inches across. One thousand species of cockroaches developed, and some grew to be four inches long. (680.10) 59:5.8 Two groups of echinoderms became especially well developed, and they are in reality the guide fossils of this epoch. The large shell-feeding sharks were also highly evolved, and for more than five million years they dominated the oceans. The climate was still mild and equable; the marine life was little changed. Fresh-water fish were developing and the trilobites were nearing extinction. Corals were scarce, and much of the limestone was being made by the crinoids. The finer building limestones were laid down during this epoch. (681.1) 59:5.9 The waters of many of the inland seas were so heavily charged with lime and other minerals as greatly to interfere with the progress and development of many marine species. Eventually the seas cleared up as the result of an extensive stone deposit, in some places containing zinc and lead. (681.2) 59:5.10 The deposits of this early Carboniferous age are from 500 to 2,000 feet thick, consisting of sandstone, shale, and limestone. The oldest strata yield the fossils of both land and marine animals and plants, along with much gravel and basin sediments. Little workable coal is found in these older strata. These depositions throughout Europe are very similar to those laid down over North America. (681.3) 59:5.11 Toward the close of this epoch the land of North America began to rise. There was a short interruption, and the sea returned to cover about half of its previous beds. This was a short inundation, and most of the land was soon well above water. South America was still connected with Europe by way of Africa. (681.4) 59:5.12 This epoch witnessed the beginning of the Vosges, Black Forest, and Ural mountains. Stumps of other and older mountains are to be found all over Great Britain and Europe. (681.5) 59:5.13 200,000,000 years ago the really active stages of the Carboniferous period began. For twenty million years prior to this time the earlier coal deposits were being laid down, but now the more extensive coal-formation activities were in process. The length of the actual coal-deposition epoch was a little over twenty-five million years. (681.6) 59:5.14 The land was periodically going up and down due to the shifting sea level occasioned by activities on the ocean bottoms. This crustal uneasiness — the settling and rising of the land — in connection with the prolific vegetation of the coastal swamps, contributed to the production of extensive coal deposits, which have caused this period to be known as the Carboniferous. And the climate was still mild the world over. (681.7) 59:5.15 The coal layers alternate with shale, stone, and conglomerate. These coal beds over central and eastern United States vary in thickness from forty to fifty feet. But many of these deposits were washed away during subsequent land elevations. In some parts of North America and Europe the coal-bearing strata are 18,000 feet in thickness. (681.8) 59:5.16 The presence of roots of trees as they grew in the
Life Establishment on Urantia (664.1) 58:0.1 IN ALL Satania there are only sixty-one worlds similar to Urantia, life-modification planets. The majority of inhabited worlds are peopled in accordance with established techniques; on such spheres the Life Carriers are afforded little leeway in their plans for life implantation. But about one world in ten is designated as a decimal planet and assigned to the special registry of the Life Carriers; and on such planets we are permitted to undertake certain life experiments in an effort to modify or possibly improve the standard universe types of living beings. 1. Physical-Life Prerequisites (664.2) 58:1.1 600,000,000 years ago the commission of Life Carriers sent out from Jerusem arrived on Urantia and began the study of physical conditions preparatory to launching life on world number 606 of the Satania system. This was to be our six hundred and sixth experience with the initiation of the Nebadon life patterns in Satania and our sixtieth opportunity to make changes and institute modifications in the basic and standard life designs of the local universe. (664.3) 58:1.2 It should be made clear that Life Carriers cannot initiate life until a sphere is ripe for the inauguration of the evolutionary cycle. Neither can we provide for a more rapid life development than can be supported and accommodated by the physical progress of the planet. (664.4) 58:1.3 The Satania Life Carriers had projected a sodium chloride pattern of life; therefore no steps could be taken toward planting it until the ocean waters had become sufficiently briny. The Urantia type of protoplasm can function only in a suitable salt solution. All ancestral life — vegetable and animal — evolved in a salt-solution habitat. And even the more highly organized land animals could not continue to live did not this same essential salt solution circulate throughout their bodies in the blood stream which freely bathes, literally submerses, every tiny living cell in this “briny deep.” (664.5) 58:1.4 Your primitive ancestors freely circulated about in the salty ocean; today, this same oceanlike salty solution freely circulates about in your bodies, bathing each individual cell with a chemical liquid in all essentials comparable to the salt water which stimulated the first protoplasmic reactions of the first living cells to function on the planet. (664.6) 58:1.5 But as this era opens, Urantia is in every way evolving toward a state favorable for the support of the initial forms of marine life. Slowly but surely physical developments on earth and in adjacent space regions are preparing the stage for the later attempts to establish such life forms as we had decided would be best adapted to the unfolding physical environment — both terrestrial and spatial. (665.1) 58:1.6 Subsequently the Satania commission of Life Carriers returned to Jerusem, preferring to await the further breakup of the continental land mass, which would afford still more inland seas and sheltered bays, before actually beginning life implantation. (665.2) 58:1.7 On a planet where life has a marine origin the ideal conditions for life implantation are provided by a large number of inland seas, by an extensive shore line of shallow waters and sheltered bays; and just such a distribution of the earth’s waters was rapidly developing. These ancient inland seas were seldom over five or six hundred feet deep, and sunlight can penetrate ocean water for more than six hundred feet. (665.3) 58:1.8 And it was from such seashores of the mild and equable climes of a later age that primitive plant life found its way onto the land. There the high degree of carbon in the atmosphere afforded the new land varieties of life opportunity for speedy and luxuriant growth. Though this atmosphere was then ideal for plant growth, it contained such a high degree of carbon dioxide that no animal, much less man, could have lived on the face of the earth. 2. The Urantia Atmosphere (665.4) 58:2.1 The planetary atmosphere filters through to the earth about one two-billionth of the sun’s total light emanation. If the light falling upon North America were paid for at the rate of two cents per kilowatt-hour, the annual light bill would be upward of 800 quadrillion dollars. Chicago’s bill for sunshine would amount to considerably over 100 million dollars a day. And it should be remembered that you receive from the sun other forms of energy — light is not the only solar contribution reaching your atmosphere. Vast solar energies pour in upon Urantia embracing wave lengths ranging both above and below the recognition range of human vision.* (665.5) 58:2.2 The earth’s atmosphere is all but opaque to much of the solar radiation at the extreme ultraviolet end of the spectrum. Most of these short wave lengths are absorbed by a layer of ozone which exists throughout a level about ten miles above the surface of the earth, and which extends spaceward for another ten miles. The ozone permeating this region, at conditions prevailing on the earth’s surface, would make a layer only one tenth of an inch thick; nevertheless, this relatively small and apparently insignificant amount of ozone protects Urantia inhabitants from the excess of these dangerous and destructive ultraviolet radiations present in sunlight. But were this ozone layer just a trifle thicker, you would be deprived of the highly important and health-giving ultraviolet rays which now reach the earth’s surface, and which are ancestral to one of the most essential of your vitamins. (665.6) 58:2.3 And yet some of the less imaginative of your mortal mechanists insist on viewing material creation and human evolution as an accident. The Urantia midwayers have assembled over fifty thousand facts of physics and chemistry which they deem to be incompatible with the laws of accidental chance, and which they contend unmistakably demonstrate the presence of intelligent purpose in the material creation. And all of this takes no account of their catalogue of more than one hundred thousand findings outside the domain of physics and chemistry which they maintain prove the presence of mind in the planning, creation, and maintenance of the material cosmos. (666.1) 58:2.4 Your sun pours forth a veritable flood of death-dealing rays, and your pleasant life on Urantia is due to the “fortuitous” influence of more than two-score apparently accidental protective operations similar to the action of this unique ozone layer. (666.2) 58:2.5 Were it not for the “blanketing” effect of the atmosphere at night, heat would be lost by radiation so rapidly that life would be impossible of maintenance except by artificial provision. (666.3) 58:2.6 The lower five or six miles of the earth’s atmosphere is the troposphere; this is the region of winds and air currents which provide weather phenomena. Above this region is the inner ionosphere and next above is the stratosphere. Ascending from the surface of the earth, the temperature steadily falls for six or eight miles, at which height it registers around 70 degrees below zero F. This temperature range of from 65 to 70 degrees below zero F. is unchanged in the further ascent for forty miles; this realm of constant temperature is the stratosphere. At a height of forty-five or fifty miles, the temperature begins to rise, and this increase continues until, at the level of the auroral displays, a temperature of 1200° F. is attained, and it is this intense heat that ionizes the oxygen. But temperature in such a rarefied atmosphere is hardly comparable with heat reckoning at the surface of the earth. Bear in mind that one half of all your atmosphere is to be found in the first three miles. The height of the earth’s atmosphere is indicated by the highest auroral streamers — about four hundred miles. (666.4) 58:2.7 Auroral phenomena are directly related to sunspots, those solar cyclones which whirl in opposite directions above and below the solar equator, even as do the terrestrial tropical hurricanes. Such atmospheric disturbances whirl in opposite directions when occurring above or below the equator. (666.5) 58:2.8 The power of sunspots to alter light frequencies shows that these solar storm centers function as enormous magnets. Such magnetic fields are able to hurl charged particles from the sunspot craters out through space to the earth’s outer atmosphere, where their ionizing influence produces such spectacular auroral displays. Therefore do you have the greatest auroral phenomena when sunspots are at their height — or soon thereafter — at which time the spots are more generally equatorially situated. (666.6) 58:2.9 Even the compass needle is responsive to this solar influence since it turns slightly to the east as the sun rises and slightly to the west as the sun nears setting. This happens every day, but during the height of sunspot cycles this variation of the compass is twice as great. These diurnal wanderings of the compass are in response to the increased ionization of the upper atmosphere, which is produced by the sunlight. (666.7) 58:2.10 It is the presence of two different levels of electrified conducting regions in the superstratosphere that accounts for the long-distance transmission of your long- and short-wave radiobroadcasts. Your broadcasting is sometimes disturbed by the terrific storms which occasionally rage in the realms of these outer ionospheres. 3. Spatial Environment (666.8) 58:3.1 During the earlier times of universe materialization the space regions are interspersed with vast hydrogen clouds, just such astronomic dust clusters as now characterize many regions throughout remote space. Much of the organized matter which the blazing suns break down and disperse as radiant energy was originally built up in these early appearing hydrogen clouds of space. Under certain unusual conditions atom disruption also occurs at the nucleus of the larger hydrogen masses. And all of these phenomena of atom building and atom dissolution, as in the highly heated nebulae, are attended by the emergence of flood tides of short space rays of radiant energy. Accompanying these diverse radiations is a form of space-energy unknown on Urantia. (667.1) 58:3.2 This short-ray energy charge of universe space is four hundred times greater than all other forms of radiant energy existing in the organized space domains. The output of short space rays, whether coming from the blazing nebulae, tense electric fields, outer space, or the vast hydrogen dust clouds, is modified qualitatively and quantitatively by fluctuations of, and sudden tension changes in, temperature, gravity, and electronic pressures. (667.2) 58:3.3 These eventualities in the origin of the space rays are determined by many cosmic occurrences as well as by the orbits of circulating matter, which vary from modified circles to extreme ellipses. Physical conditions may also be greatly altered because the electron spin is sometimes in the opposite direction from that of the grosser matter behavior, even in the same physical zone. (667.3) 58:3.4 The vast hydrogen clouds are veritable cosmic chemical laboratories, harboring all phases of evolving energy and metamorphosing matter. Great energy actions also occur in the marginal gases of the great binary stars which so frequently overlap and hence extensively commingle. But none of these tremendous and far-flung energy activities of space exerts the least influence upon the phenomena of organized life — the germ plasm of living things and beings. These energy conditions of space are germane to the essential environment of life establishment, but they are not effective in the subsequent modification of the inheritance factors of the germ plasm as are some of the longer rays of radiant energy. The implanted life of the Life Carriers is fully resistant to all of this amazing flood of the short space rays of universe energy. (667.4) 58:3.5 All of these essential cosmic conditions had to evolve to a favorable status before the Life Carriers could actually begin the establishment of life on Urantia. 4. The Life-Dawn Era (667.5) 58:4.1 That we are called Life Carriers should not confuse you. We can and do carry life to the planets, but we brought no life to Urantia. Urantia life is unique, original with the planet. This sphere is a life-modification world; all life appearing hereon was formulated by us right here on the planet; and there is no other world in all Satania, even in all Nebadon, that has a life existence just like that of Urantia. (667.6) 58:4.2 550,000,000 years ago the Life Carrier corps returned to Urantia. In co-operation with spiritual powers and superphysical forces we organized and initiated the original life patterns of this world and planted them in the hospitable waters of the realm. All planetary life (aside from extraplanetary personalities) down to the days of Caligastia, the Planetary Prince, had its origin in our three original, identical, and simultaneous marine-life implantations. These three life implantations have been designated as: the central or Eurasian-African, the eastern or Australasian, and the western, embracing Greenland and the Americas. (668.1) 58:4.3 500,000,000 years ago primitive marine vegetable life was well established on Urantia. Greenland and the arctic land mass, together with North and South America, were beginning their long and slow westward drift. Africa moved slightly south, creating an east and west trough, the Mediterranean basin, between itself and the mother body. Antarctica, Australia, and the land indicated by the islands of the Pacific broke away on the south and east and have drifted far away since that day. (668.2) 58:4.4 We had planted the primitive form of marine life in the sheltered tropic bays of the central seas of the east-west cleavage of the breaking-up continental land mass. Our purpose in making three marine-life implantations was to insure that each great land mass would carry this life with it, in its warm-water seas, as the land subsequently separated. We foresaw that in the later era of the emergence of land life large oceans of water would separate these drifting continental land masses. 5. The Continental Drift (668.3) 58:5.1 The continental land drift continued. The earth’s core had become as dense and rigid as steel, being subjected to a pressure of almost 25,000 tons to the square inch, and owing to the enormous gravity pressure, it was and still is very hot in the deep interior. The temperature increases from the surface downward until at the center it is slightly above the surface temperature of the sun. (668.4) 58:5.2 The outer one thousand miles of the earth’s mass consists principally of different kinds of rock. Underneath are the denser and heavier metallic elements. Throughout the early and preatmospheric ages the world was so nearly fluid in its molten and highly heated state that the heavier metals sank deep into the interior. Those found near the surface today represent the exudate of ancient volcanoes, later and extensive lava flows, and the more recent meteoric deposits. (668.5) 58:5.3 The outer crust was about forty miles thick. This outer shell was supported by, and rested directly upon, a molten sea of basalt of varying thickness, a mobile layer of molten lava held under high pressure but always tending to flow hither and yon in equalization of shifting planetary pressures, thereby tending to stabilize the earth’s crust. (668.6) 58:5.4 Even today the continents continue to float upon this noncrystallized cushiony sea of molten basalt. Were it not for this protective condition, the more severe earthquakes would literally shake the world to pieces. Earthquakes are caused by sliding and shifting of the solid outer crust and not by volcanoes. (668.7) 58:5.5 The lava layers of the earth’s crust, when cooled, form granite. The average density of Urantia is a little more than five and one-half times that of water; the density of granite is less than three times that of water. The earth’s core is twelve times as dense as water. (668.8) 58:5.6 The sea bottoms are more dense than the land masses, and this is what keeps the continents above water. When the sea bottoms are extruded above the sea level, they are found to consist largely of basalt, a form of lava considerably heavier than the granite of the land masses. Again, if the continents were not lighter than the ocean beds, gravity would draw the edges of the oceans up onto the land, but such phenomena are not observable. (668.9) 58:5.7 The weight of the oceans is also a factor in the increase of pressure on the sea beds. The lower but comparatively heavier ocean beds, plus the weight of the overlying water, approximate the weight of the higher but much lighter continents. But all continents tend to creep into the oceans. The continental pressure at ocean-bottom levels is about 20,000 pounds to the square inch. That is, this would be the pressure of a continental mass standing 15,000 feet above the ocean floor. The ocean-floor water pressure is only about 5,000 pounds to the square inch. These differential pressures tend to cause the continents to slide toward the ocean beds. (669.1) 58:5.8 Depression of the ocean bottom during the prelife ages had upthrust a solitary continental land mass to such a height that its lateral pressure tended to cause the eastern, western, and southern fringes to slide downhill, over the underlying semiviscous lava beds, into the waters of the surrounding Pacific Ocean. This so fully compensated the continental pressure that a wide break did not occur on the eastern shore of this ancient Asiatic continent, but ever since has that eastern coast line hovered over the precipice of its adjoining oceanic depths, threatening to slide into a watery grave. 6. The Transition Period (669.2) 58:6.1 450,000,000 years ago the transition from vegetable to animal life occurred. This metamorphosis took place in the shallow waters of the sheltered tropic bays and lagoons of the extensive shore lines of the separating continents. And this development, all of which was inherent in the original life patterns, came about gradually. There were many transitional stages between the early primitive vegetable forms of life and the later well-defined animal organisms. Even today the transition slime molds persist, and they can hardly be classified either as plants or as animals. (669.3) 58:6.2 Although the evolution of vegetable life can be traced into animal life, and though there have been found graduated series of plants and animals which progressively lead up from the most simple to the most complex and advanced organisms, you will not be able to find such connecting links between the great divisions of the animal kingdom nor between the highest of the prehuman animal types and the dawn men of the human races. These so-called “missing links” will forever remain missing, for the simple reason that they never existed. (669.4) 58:6.3 From era to era radically new species of animal life arise. They do not evolve as the result of the gradual accumulation of small variations; they appear as full-fledged and new orders of life, and they appear suddenly. (669.5) 58:6.4 The sudden appearance of new species and diversified orders of living organisms is wholly biologic, strictly natural. There is nothing supernatural connected with these genetic mutations. (669.6) 58:6.5 At the proper degree of saltiness in the oceans animal life evolved, and it was comparatively simple to allow the briny waters to circulate through the animal bodies of marine life. But when the oceans were contracted and the percentage of salt was greatly increased, these same animals evolved the ability to reduce the saltiness of their body fluids just as those organisms which learned to live in fresh water acquired the ability to maintain the proper degree of sodium chloride in their body fluids by ingenious techniques of salt conservation. (669.7) 58:6.6 Study of the rock-embraced fossils of marine life reveals the early adjustment struggles of these primitive organisms. Plants and animals never cease to make these adjustment experiments. Ever the environment is changing, and always are living organisms striving to accommodate themselves to these never-ending fluctuations. (670.1) 58:6.7 The physiologic equipment and the anatomic structure of all new orders of life are in response to the action of physical law, but the subsequent endowment of mind is a bestowal of the adjutant mind-spirits in accordance with innate brain capacity. Mind, while not a physical evolution, is wholly dependent on the brain capacity afforded by purely physical and evolutionary developments. (670.2) 58:6.8 Through almost endless cycles of gains and losses, adjustments and readjustments, all living organisms swing back and forth from age to age. Those that attain cosmic unity persist, while those that fall short of this goal cease to exist. 7. The Geologic History Book (670.3) 58:7.1 The vast group of rock systems which constituted the outer crust of the world during the life-dawn or Proterozoic era does not now appear at many points on the earth’s surface. And when it does emerge from below all the accumulations of subsequent ages, there will be found only the fossil remains of vegetable and early primitive animal life. Some of these older water-deposited rocks are commingled with subsequent layers, and sometimes they yield fossil remains of some of the earlier forms of vegetable life, while on the topmost layers occasionally may be found some of the more primitive forms of the early marine-animal organisms. In many places these oldest stratified rock layers, bearing the fossils of the early marine life, both animal and vegetable, may be found directly on top of the older undifferentiated stone. (670.4) 58:7.2 Fossils of this era yield algae, corallike plants, primitive Protozoa, and spongelike transition organisms. But the absence of such fossils in the early rock layers does not necessarily prove that living things were not elsewhere in existence at the time of their deposition. Life was sparse throughout these early times and only slowly made its way over the face of the earth. (670.5) 58:7.3 The rocks of this olden age are now at the earth’s surface, or very near the surface, over about one eighth of the present land area. The average thickness of this transition stone, the oldest stratified rock layers, is about one and one-half miles. At some points these ancient rock systems are as much as four miles thick, but many of the layers which have been ascribed to this era belong to later periods. (670.6) 58:7.4 In North America this ancient and primitive fossil-bearing stone layer comes to the surface over the eastern, central, and northern regions of Canada. There is also an intermittent east-west ridge of this rock which extends from Pennsylvania and the ancient Adirondack Mountains on west through Michigan, Wisconsin, and Minnesota. Other ridges run from Newfoundland to Alabama and from Alaska to Mexico. (670.7) 58:7.5 The rocks of this era are exposed here and there all over the world, but none are so easy of interpretation as those about Lake Superior and in the Grand Canyon of the Colorado River, where these primitive fossil-bearing rocks, existing in several layers, testify to the upheavals and surface fluctuations of those faraway times. (670.8) 58:7.6 This stone layer, the oldest fossil-bearing stratum in the crust of the earth, has been crumpled, folded, and grotesquely twisted as a result of the upheavals of earthquakes and the early volcanoes. The lava flows of this age brought much iron, copper, and lead up near the planetary surface. (670.9) 58:7.7 There are few places on the earth where such activities are more graphically shown than in the St. Croix valley of Wisconsin. In this region there occurred one hundred and twenty-seven successive lava flows on land with succeeding water submergence and consequent rock deposition. Although much of the upper rock sedimentation and intermittent lava flow is absent today, and though the bottom of this system is buried deep in the earth, nevertheless, about sixty-five or seventy of these stratified records of past ages are now exposed to view. (671.1) 58:7.8 In these early ages when much land was near sea level, there occurred many successive submergences and emergences. The earth’s crust was just entering upon its later period of comparative stabilization. The undulations, rises and dips, of the earlier continental drift contributed to the frequency of the periodic submergence of the great land masses. (671.2) 58:7.9 During these times of primitive marine life, extensive areas of the continental shores sank beneath the seas from a few feet to half a mile. Much of the older sandstone and conglomerates represents the sedimentary accumulations of these ancient shores. The sedimentary rocks belonging to this early stratification rest directly upon those layers which date back far beyond the origin of life, back to the early appearance of the world-wide ocean. (671.3) 58:7.10 Some of the upper layers of these transition rock deposits contain small amounts of shale or slate of dark colors, indicating the presence of organic carbon and testifying to the existence of the ancestors of those forms of plant life which overran the earth during the succeeding Carboniferous or coal age. Much of the copper in these rock layers results from water deposition. Some is found in the cracks of the older rocks and is the concentrate of the sluggish swamp water of some ancient sheltered shore line. The iron mines of North America and Europe are located in deposits and extrusions lying partly in the older unstratified rocks and partly in these later stratified rocks of the transition periods of life formation. (671.4) 58:7.11 This era witnesses the spread of life throughout the waters of the world; marine life has become well established on Urantia. The bottoms of the shallow and extensive inland seas are being gradually overrun by a profuse and luxuriant growth of vegetation, while the shore-line waters are swarming with the simple forms of animal life. (671.5) 58:7.12 All of this story is graphically told within the fossil pages of the vast “stone book” of world record. And the pages of this gigantic biogeologic record unfailingly tell the truth if you but acquire skill in their interpretation. Many of these ancient sea beds are now elevated high upon land, and their deposits of age upon age tell the story of the life struggles of those early days. It is literally true, as your poet has said, “The dust we tread upon was once alive.” (671.6) 58:7.13 [Presented by a member of the Urantia Life Carrier Corps now resident on the planet.]
In this episode, the gang discusses two papers that look at the ecology of the early life forms of the Ediacaran period. Also, James discusses the American dream, Curt details the secrets of the podcast's "success", and Amanda is nearly murdered by her cat. References: Carbone, Calla, and Guy M. Narbonne. "When life got smart: the evolution of behavioral complexity through the Ediacaran and early Cambrian of NW Canada." Journal of Paleontology 88.2 (2014): 309-330. Cuthill, Jennifer F. Hoyal, and Simon Conway Morris. "Fractal branching organizations of Ediacaran rangeomorph fronds reveal a lost Proterozoic body plan." Proceedings of the National Academy of Sciences (2014): 201408542.
Fakultät für Geowissenschaften - Digitale Hochschulschriften der LMU
Although remote sensing has been widely used in geological investigations, the lithological classification of the area interested, based on medium-spatial and spectral resolution satellite data, is often not successful because of the complicated geological situation and other factors like inadequate methodology applied and wrong geological models. The study area of the present thesis is located in southwest of the Prieska sub-basin, Transvaal Supergroup, South Africa. This area includes mainly Neoarchean and Proterozoic sedimentary rocks partly uncomfortably covered by uppermost Paleozoic and lower Mesozoic rocks and Tertiary to recent soils and sands. The Precambrian rocks include various formations of volcanic and intrusive rocks, quartzites, shales, platform carbonates and Banded Iron Formations (BIF). The younger rocks and soils include dikes and shales, glacial sedimentary rocks, coarser siliciclastic rocks, calcretes, aeolian and fluvial sands, etc. Prospect activity for mineral deposits necessitates the detailed geological map (1:100000) of the area. In this research, a new rule-based classification system (RBS) was put forward, integrating spectral characteristics, textural features and ancillary data, such as general geological map (1:250000) and elevation data, in order to improve the lithological classification accuracy and the subsequent mapping accuracy in the study area. The proposed technique was mainly based on Landsat TM data and ASTER data with medium resolution. As ancillary data sets, topographic maps and general geological map were also available. Software like ERDAS©, Matlab©, and ArcGIS© supported the procedures of classification and mapping. The newly developed classification technique was performed by three steps. Firstly, the geographic and atmospheric correction was performed on the original TM and ASTER data, following the principal component analysis (PCA) and band ratioing, to enhance the images and to obtain data sets like principal components (PCs) and ratio bands. Traditional maximum-likelihood supervised classification (MLC) was performed individually on enhanced multispectral image and principal components image (PCs-image). For TM data, the classification accuracy based on PCs-image was higher than that based on multispectral image. For ASTER data, the classification accuracy of PCs- image was close to but lower, than that of multispectral image. As one of the encountered Banded Iron Formations, the Griquatown Banded Iron Formation (G-BIF) was recognized well in TM-principal components image (PCs-image). In the second step, textural features of different lithological types based on TM data were analyzed. Grey level co-occurrence matrix (GLCM) based textural features were computed individually from band 5 and the first principal component (PC1) of TM data. Geostatistics-based textural features were computed individually from the 6 TM multispectral bands and 3 principal components (PC1, PC2 and PC3). These two kinds of textural features were individually stacked as extra layers together with the original 6 multispectral bands and the 6 principal components to form several new data sets. Ratio bands were also individually stacked as extra layers with 6 multispectral bands and 6 principal components, to form other new data sets. In the same way new data sets were formed based on ASTER data. Then, all of the new data sets were individually classified using a maximum likelihood supervised classification (MLC), to produce several classified thematic images. The classification accuracy based on the new data sets are higher than that solely based on the spectral characteristics of original TM and ASTER data. It should be noticed that for one specific rock type, the class value in all classified images should correspond to its identified (ID) value in digital geological map. The third step was to perform the rule-based system (RBS) classification. In the first part of the RBS, two classified images were analyzed and compared. The analysis was based on the classification results in the first step, and the elevation data detracted from the topographic map. In comparison, the pixels with high possibility of being classified correctly (consistent pixels) and the pixels with high possibility of being misclassified (inconsistent pixels) were separately marked. In the second part of the RBS, the class values of consistent pixels were kept unchanged, and the class values of inconsistent pixels were replaced by their values in digital geological map (1:250000). Compared to the results solely based on spectral characteristics of TM data (54.3%) and ASTER data (66.41%), the new RBS classification improved the accuracy (83.2%) significantly. Based on the classification results, the detailed lithological map (1:100000) of the study area was edited. Photo-lineaments were interpreted from multi data source (MDS), including enhanced satellite images, slope images, shaded relief images and drainage maps. The interpreted lineaments were compared to those, digitized from general geological map and followed by a simple lineament analysis compared to published literatures. The results show the individual merits of lineament detection from MDS and general geological map. A final lineament map (1:100000) was obtained by integrating all the information. Ground check field work was carried out in 2009, to verify the classification and mapping, and the results were subsequently incorporated into the mapping and the classification procedures. Finally, a GIS-based detailed geological map (1:100000) of the study area was obtained, compiling the newly gained information from the performed classification and lineament analysis, from the field work and from published and available unpublished detailed geological maps. The here developed methods are proposed to be used for generation of new, detailed geological maps or updates of existent general geological maps by implementing the latest satellite images and all available ancillary data sets. Although final ground check field work is irreplaceable by remote sensing, the here presented research demonstrates the great potential and future prospects in lithological classification and geological mapping, for mineral exploration.
Transcript -- The ductility of structures of rocks from the Dalradian supergroup.
The ductility of structures of rocks from the Dalradian supergroup.
Transcript -- The ductility of structures of rocks from the Dalradian supergroup.
The ductility of structures of rocks from the Dalradian supergroup.
Melvyn Bragg and guests discuss the age of the Earth. It was once thought that the world began in 4004 BC. Lord Kelvin calculated the cooling temperature of a rock the size of our planet and came up with a figure of 20 million years for the age of the Earth. Now, the history of our planet is divided into four great Eons: the Hadean, the Archaen, the Proterozoic and the Phanerozoic. Together, they are taken to encompass an incredible four and a half billion years. How can we begin to make sense of such a huge swathe of time? And can we be sure that we have got the Earth's age right? Geologists use Eras, Periods and Epochs to further punctuate what's known as 'Deep Time', but can we be sure that the classifications we use don't obscure more than they reveal? With Richard Corfield, Research Associate in the Department of Earth Sciences at Oxford University; Hazel Rymer, Senior Lecturer in the Department of Earth Sciences at the Open University; Henry Gee, Senior Editor at Nature.
Melvyn Bragg and guests discuss the age of the Earth. It was once thought that the world began in 4004 BC. Lord Kelvin calculated the cooling temperature of a rock the size of our planet and came up with a figure of 20 million years for the age of the Earth. Now, the history of our planet is divided into four great Eons: the Hadean, the Archaen, the Proterozoic and the Phanerozoic. Together, they are taken to encompass an incredible four and a half billion years. How can we begin to make sense of such a huge swathe of time? And can we be sure that we have got the Earth's age right? Geologists use Eras, Periods and Epochs to further punctuate what's known as 'Deep Time', but can we be sure that the classifications we use don't obscure more than they reveal? With Richard Corfield, Research Associate in the Department of Earth Sciences at Oxford University; Hazel Rymer, Senior Lecturer in the Department of Earth Sciences at the Open University; Henry Gee, Senior Editor at Nature.
Fakultät für Geowissenschaften - Digitale Hochschulschriften der LMU
In the South Indian basement, several crustal-scale amphibolite facies shear zones occur between high-grade metamorphic units with a different geological history: the EW-trending Moyar Shear Zone (MSZ) is a zone of predominantly dip-slip transport separating the Archaean Dharwar Craton in the north from the late Archaean Nilgiri Block in the south. The NE-SW-trending, dextral-transpressive Bhavani Shear Zone (BSZ) constitutes the southern boundary of the Nilgiri Block in its western part and bounds the southern Dharwar Craton further east. South of the BSZ, the high-grade metasediments and metaintrusives of the Maddukarai region are separated from the 0.6 Ga-metamorphic Madurai Block by the EW-trending dextral Palghat Shear Zone (PSZ). MSZ, BSZ and PSZ are regarded as parts of the prominent Cauvery shear system. The N-S-trending sinistral Kollegal Shear Zone (KSZ), which transects the Dharwar Craton, is cut off by the Cauvery shear system. These shear zones play an important role in reconstructing the position of India within the East Gondwana terrane assembly. A combined Sm-Nd, Rb-Sr and U-Pb isotopic study was carried out on granulite remnants, amphibolite facies (mylonitic) gneisses and pre-, syn- und postmetamorphic intrusives in order to examine the tectonometamorphic evolution of the MSZ, BSZ, PSZ and KSZ. Whole rock data The majority of relic and retrogressed granulites from the MSZ (TDM 2.3–3.1 Ga) and BSZ (TDM 2.6-2.9 Ga) show late Archaean average crustal residence ages. With respect to their LIL-, Nb-depleted tonalitic nature and Nd-model ages, these rocks resemble the neighbouring Nilgiri granulites. Mylonitic gneisses and granulite remnants from the BSZ yielded a Sm-Nd-whole rock-age of 2520 ± 150 Ma (εNd(t) +0.6; MSWD = 2.2), which is interpreted as protolith age. I-Type granites and tonalites, which intruded the MSZ ~620 Ma ago (87Sr/86Sri 0.7039), gave unusually young Nd model ages of 1.8-1.9 Ma suggesting derivation from a Mid- to Neoproterozoic upper mantle source, presumably with minor contribution of an older crust. An allochthonous quarzite (TDM 3.3 Ga) of the BSZ is regarded as counterpart of the Archaean Sargur group, which is exposed in schist belts of the Dharwar Craton. As suggested by geochemical features (LIL-, Nd-rich granitoids) and Neoarchaean-Palaeoproterozoic Nd-model ages (TDM 2.3-3.0 Ga), the PSZ-gneisses show affinity to the adjacent Madurai Block. Sheared orthogneisses from the KSZ show Mesoarchaean average crustal residence ages (TDM 3.2-3.3 Ga) typical for Dharwar Craton gneisses. Mineral dating on granulites Mineral age data of relic granulites from the MSZ, BSZ and PSZ provide evidence for the metamorphic precursor history of the shear zone rocks: gnt-plag-px-granulites from low-strain domains yielded Sm-Ndgarnet- whole rock ages of 2355 ± 22 Ma (εNd(t) -1.4) for the MSZ and 2329 ± 19 Ma (εNd(t) -2.0) for the BSZ, both recording late-stage Palaeoproterozoic granulitisation of the rocks and corresponding with garnet data from the Nilgiri Block. Correlated low εNd-initial values reflect the short time span between crustal genesis and garnet crystallisation. Further Sm-Nd mineral data from BSZ-granulites are between 1275 ± 10 Ma and 1106 ± 48 Ma (garnet/plagioclase-whole rock-pairs; εNd(t) –5.8 to –25.4), indicating a Mesoproterozoic metamorphic imprint. A charnockite from the southern BSZ, which is interpreted as a separate lithological unit, yielded a reproducable Sm-Nd-garnet-whole rock age of 1705 ± 11 Ma (εNd(t) –12.4), presumably recording late Palaeoproterozoic metamorphism. Mineral dating on gneisses and younger intrusives Amphibolite facies rocks with younger fabrics yielded Neoproterozoic to early Palaeozoic mineral age data for the MSZ, BSZ and PSZ: Sm-Nd mineral ages from gneiss-mylonites imply a first stage of early Pan-African shearing in the MSZ ~745 Ma ago (garnet/plagioclase-hornblende-pairs: 743 ± 13 Ma, 747 ± 75 Ma) and in the BSZ ~730 Ma ago (garnetwhole rock-pair: 726 ± 9 Ma). This tectonic stage immediately followed a period of anorogenic alkalimagmatism in the eastern continuation of the BSZ suggesting that it may be attributed to an overall extensive regime. A second stage of late Pan-African shearing in the MSZ at ~620 Ma is constrained by statistically equivalent concordant U-Pb zircon ages that are interpreted to record crystallisation of syndeformative intrusives with Itype characteristics (granite: 616 ± 19 Ma, tonalite: 633 ± 23 Ma). Coeval to slightly younger metamorphic garnet growth in adjacent MSZ-gneisses and -mylonites is reflected by Sm-Nd-garnet-whole rock ages between 624 ± 9 Ma and 591 ± 5 Ma. Subsequent postdeformative cooling in the MSZ is constrained by Rb-Sr micawhole rock ages (muscovite: 594 ± 23 Ma; biotite: 603 ± 12 Ma to 547 ± 7 Ma). The 620 Ma-shearing event in the MSZ predates late Pan-African tectonometamorphism in the BSZ, which, according to garnet crystallisation, occurred ~550 Ma ago (Deters-Umlauf, 1997). Amphibolite facies shear deformation in the PSZ is even younger, as suggested by a Sm-Nd-garnet-whole rock age of 521 ± 8 Ma. A lower limit for the age of ductile shearing in the BSZ is provided by a Sm-Nd-garnet-whole rock-age of 513 ± 5 Ma reflecting postdeformative emplacement of a pegmatitic dyke in mylonitic host gneisses. According to Rb- Sr-mica age dating, postdeformative cooling of the sheared BSZ-gneisses (biotite-whole rock-pairs: 508 to 491 ± 12 Ma) and the undeformed dyke (muscovite-K'feldspar: 504 ± 13 Ma, biotite-K'feldspar: 488 ± 12 Ma) as well as cooling of the PSZ-gneisses (biotite-whole rock-pairs: 486, 487 and 488 ± 12 Ma) may have been slightly diachronous. In summary, the new geochronological data provide evidence for non-synchronousity of late Pan-African tectonometamorphism in the MSZ, BSZ and PSZ. At the time of structurally-controlled amphibolite facies metamorphism, all reworked gneisses had negative εNd(t) values (–24.7 to -9.4) reflecting their earlier crustal evolution. Sinistral shearing along the KSZ is not related to Pan-African processes, but has to be attributed to Palaeoproterozoic metamorphism in the Dharwar Craton: a lower limit for ductile tectonics is provided by a Sm- Nd-garnet-whole rock age of 2388 ± 16 Ma (εNd(t) –7.3). Strikingly younger Rb-Sr biotite-whole rock ages of 2137 ± 52 Ma and 2091 ± 51 Ma may be explained by local reheating of the crust that exceeded the closure temperature of biotite. The new results support the idea of a terrane boundary running along the southern BSZ. This terrane boundary separates the Archaean Dharwar/Nilgiri crustal province with 2.5 Ga metamorphism from the Proterozoic mobile belt of the Madurai province with a 0.6 Ga high-grade imprint. According to geochronological data, South India and Madagascar probably were subjected to different plate-tectonic regimes in the early Neoproterozoic. Late Neoproterozoic syndeformative emplacement of mantle-derived granitoids with crustal contamination both in the MSZ (~620 Ma) and in Central-Madagascar (~ 630 Ma) may point to a neighbouring position of the two East Gondwana continents at that time.
Lower Proterozoic stromatolites and associated clastic carbonate deposits of the Campbell Group, from the southern margin (Prieska area) of the Kaapvaal Craton, northern Cape Province, are described. Contrary to previous interpretations (Beukes, 1978; 1980a) shallow subtidal to supratidal facies are recognised and discussed in regional context. An alternative model for the facies development of the Campbell Group is proposed.