12.007 Geobiology Spring 2009
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Large and Robust Lenticular Microorganisms on the Young Earth ⇑ ⇑ Dorothy Z
Precambrian Research 296 (2017) 112–119 Contents lists available at ScienceDirect Precambrian Research journal homepage: www.elsevier.com/locate/precamres Large and robust lenticular microorganisms on the young Earth ⇑ ⇑ Dorothy Z. Oehler a, , Maud M. Walsh b, Kenichiro Sugitani c, Ming-Chang Liu d, Christopher H. House e, a Planetary Science Institute, Tucson, AZ 85719, USA b School of Plant, Environmental and Soil Sciences, Louisiana State University, Baton Rouge, LA 70803-2110, USA c Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan d Department of Earth, Planetary, and Space Sciences, University of California at Los Angeles, Los Angeles, CA 90095-1567, USA e Department of Geosciences, The Pennsylvania State University, University Park, PA 16802, USA article info abstract Article history: In recent years, remarkable organic microfossils have been reported from Archean deposits in the Pilbara Received 18 November 2016 craton of Australia. The structures are set apart from other ancient microfossils by their complex lentic- Revised 29 March 2017 ular morphology combined with their large size and robust, unusually thick walls. Potentially similar Accepted 11 April 2017 forms were reported in 1992 from the 3.4 Ga Kromberg Formation (KF) of the Kaapvaal craton, South Available online 26 April 2017 Africa, but their origin has remained uncertain. Here we report the first determination of in situ carbon isotopic composition (d13C) of the lenticular structures in the KF (obtained with Secondary Ion Mass Keywords: Spectrometry [SIMS]) as well as the first comparison of these structures to those from the Pilbara, using Archean morphological, isotopic, and sedimentological criteria. Spindle Lenticular Our results support interpretations that the KF forms are bona fide, organic Archean microfossils and Microfossil represent some of the oldest morphologically preserved organisms on Earth. -
Gangidine NASA Early Career Collaboration Follow-Up
NASA Astrobiology Early Career Collaboration Award Follow-up Report Andrew Gangidine, Ph.D Candidate, University of Cincinnati Project Title: A Step Back in Time – Ancient Hot Springs and the Search for Life on Mars Collaborator: Dr. Martin Van Kranendonk, UNSW, Australian Center for Astrobiology During Summer 2018 I travel to the Pilbara Craton in Western Australia in search of the earliest known evidence of life on land. Here I met up with Dr. Martin Van Kranendonk, director of the Australian Center for Astrobiology and expert on the Pilbara geology. Over the next two weeks, we traveled to many previously established sites of interest containing stromatolitic textures and evidence of past terrestrial hot spring activity, as well as new sites of interest which provided further evidence supporting the terrestrial hot spring hypothesis. Over the course of these two weeks, I collected samples of ~3.5Ga microbial textures in order to analyze such samples for their biosignature preservation potential. I also was able to spend some time mapping the Pilbara in order to understand the greater regional geologic context of the samples I collected. After this field work, Dr. Van Kranendonk and I returned to Sydney, where I met with Dr. Malcolm Walter at the University of New South Wales. Dr. Walter allowed me to search through the sample archive of the Australian Center for Astrobiology, where I collected younger samples from the mid-Paleozoic from terrestrial hydrothermal deposits. With these samples, I am able to perform a comparison study between modern, older, and ancient hydrothermal deposits in order to characterize what happens to potential biosignatures in these environments throughout geologic time. -
Bayesian Analysis of the Astrobiological Implications of Life's
Bayesian analysis of the astrobiological implications of life's early emergence on Earth David S. Spiegel ∗ y, Edwin L. Turner y z ∗Institute for Advanced Study, Princeton, NJ 08540,yDept. of Astrophysical Sciences, Princeton Univ., Princeton, NJ 08544, USA, and zInstitute for the Physics and Mathematics of the Universe, The Univ. of Tokyo, Kashiwa 227-8568, Japan Submitted to Proceedings of the National Academy of Sciences of the United States of America Life arose on Earth sometime in the first few hundred million years Any inferences about the probability of life arising (given after the young planet had cooled to the point that it could support the conditions present on the early Earth) must be informed water-based organisms on its surface. The early emergence of life by how long it took for the first living creatures to evolve. By on Earth has been taken as evidence that the probability of abiogen- definition, improbable events generally happen infrequently. esis is high, if starting from young-Earth-like conditions. We revisit It follows that the duration between events provides a metric this argument quantitatively in a Bayesian statistical framework. By (however imperfect) of the probability or rate of the events. constructing a simple model of the probability of abiogenesis, we calculate a Bayesian estimate of its posterior probability, given the The time-span between when Earth achieved pre-biotic condi- data that life emerged fairly early in Earth's history and that, billions tions suitable for abiogenesis plus generally habitable climatic of years later, curious creatures noted this fact and considered its conditions [5, 6, 7] and when life first arose, therefore, seems implications. -
THE ARCHAEAN and Earllest PROTEROZOIC EVOLUTION and METALLOGENY of Australla
Revista Brasileira de Geociências 12(1-3): 135-148, Mar.-Sel.. 1982 - Silo Paulo THE ARCHAEAN AND EARLlEST PROTEROZOIC EVOLUTION AND METALLOGENY OF AUSTRALlA DA VID I. OROVES' ABSTRACT Proterozoic fold belts in Austrália developed by lhe reworking of Archaean base mcnt. The nature of this basement and the record of Archaean-earliest Proterozoic evolution and metallogeny is best prescrved in the Western Australian Shield. ln the Yilgarn Craton. a poorly-mineralized high-grade gneiss terrain rccords a complex,ca. 1.0 b.y. history back to ca. 3.6b.y. This terrain is probably basement to lhe ca. 2.9~2.7 b.y. granitoid -greenstone terrains to lhe east-Cratonization was essentially complete by ca, 2.6 b.y. Evolution of the granitoid-greenstone terrains ofthe Pilbara Craton occurred between ca. 3.5b.y. ano 2.8 b.y. The Iectonic seuing of ali granitoid-greenstone terrains rcmains equivocaI. Despitc coincidcnt cale -alkalinc volcanism and granitoid emplacemcnt , and broad polarity analogous to modem are and marginal basin systcrns. thcre is no direct evidencc for plate tectonic processes. Important diffcrences in regional continuity of volcanic scqucnccs, lithofacies. regional tectonic pauerns and meta1Jogeny of lhe terrains may relate to the amount of crusta! extension during basin formation. At onc extreme, basins possibly reprcsenting low total cxrensíon (e.g. east Pilbara l are poorly mi ncralizcd with some porphyry-stylc Mo-Cu and small sulphute-rich volcanogenic 01' evaporitic deposits reflecting the resultam subaerial to shaJlow-water environment. ln contrast, basins inter prctcd to have formcd during greater crusta! cxrcnsion (e.g. -
Pilbara Conservation Strategy Main Karijini National Park
Pilbara Conservation Strategy Main Karijini National Park. Foreword Photo – Judy Dunlop Over the past eight years, the Liberal National The Pilbara Conservation Strategy is a strategic It is one of only 15 national biodiversity hotspots. these projects will be an important means of funding Government has delivered greater protection for the landscape-scale approach to enhance the region’s The region has many endemic species, including the strategic landscape-scale approach for managing environment than any other government in the history high biodiversity and landscape values across property one of the richest reptile assemblages in the world, fire, feral animals and weeds and meeting the key of this State. boundaries. This initiative by the Liberal National more than 125 species of acacia and more than 1000 outcomes listed in the strategy. Government provides a vision for conservation species of aquatic invertebrates. It is an international This includes the most comprehensive biodiversity in the region. It involves partnerships with local hotspot for subterranean fauna. I invite you to join the Liberal National Government conservation laws seen in Western Australia and land managers, traditional owners, pastoralists, as a partner in this ground-breaking initiative to the implementation of the $103.6 million Kimberley conservation groups, the wider community, industry, The region has a rich and living Aboriginal culture deliver a new level of conservation management for Science and Conservation Strategy — the biggest government and non-government organisations. with traditional owners retaining strong links to the Pilbara. conservation project ever undertaken in WA, which Together, we will deliver improved on-ground country and playing a key role in protecting cultural has implemented a range of measures to retain and management of the key threats to the region’s and natural heritage. -
Pillow Basalts from the Mount Ada Basalt, Warrawoona Group, Pilbara Craton: Implications for the Initiation of Granite-Greenstone Terrains D
Goldschmidt2015 Abstracts Pillow basalts from the Mount Ada basalt, Warrawoona group, Pilbara Craton: Implications for the initiation of granite-greenstone terrains D. T. MURPHY1*, J. TROFIMOVS1, R. A. HEPPLE1, D. WIEMER1, A. I. S. KEMP2 AND A. H. HICKMAN3 1Earth, Environmental and Biological Sciences, Queensland University of Technology, 4001, Australia (correspondence: [email protected]) 2School of Earth and Environment, The University of Western Australia, 6009, Australia 3Department of Mines and Petroleum, Western Australia The Pilbara Craton represents the archetypal Archean granite-greenstone terrain in which mafic volcanic dominated supercrustals are intruded by granitic domes. This crustal morphology reflects distinct tectonic settings that formed in a hotter early Earth. The ambient temperature in the Paleoarchean mantle is estimated to be 1600oC [1] and corresponds with the liquidus temperature of Barberton komatiites [2]. In the Paleoarchean mantle a pyrolite composition at depths of less than 100 km is expected to melt and generate ultramafic magmas. Here we present volcanology, petrology and geochemistry data of well-preserved basaltic lavas ascribed to the Mount Ada Basalt, Warrawoona Group from the Doolena Gap Greenstone Belt. The Mount Ada Basalt was coeval with the Callina plutonic event that marks the initiation of dome formation in the Pilbara Craton [3]. The Doolena Gap sequence is exclusively pillow basalts with MgO < 10%. Isotopically the basalts are indistinguishable from contemporary non-chondritic Bulk Earth (εNd, 1.0 ± 0.2 and εHf, 2.3 ± 0.2). Here we address the implications of Paleoarchean basalts with MgO% < 10 derived from melting of a source indistinguishable from non-chondritic Bulk Silicate Earth to the initiation and subsequent evolution of the Pilbara Craton. -
Thomas Spring Thesis (PDF 7MB)
RECONSTRUCTION OF THE PHYSICAL VOLCANOLOGICAL PROCESSES AND PETROGENESIS OF THE 3.5GA WARRAWOONA GROUP PILLOW BASALT OF THE WARRALONG GREENSTONE BELT, PILBARA CRATON WESTERN AUSTRALIA Thomas Frederick David Spring Bachelor of Applied Science (Geology) Submitted in fulfilment of the requirements for the degree of Master of Applied Science (Geoscience) School of Earth, Environment and Biological Science Faculty of Science and Engineering Queensland University of Technology 2017 Abstract The formation of Earth’s continental crust initiated in the early Archean and has continued to the present day. In the early Archean, the Earth was substantially hotter than the present day leading to dramatically different tectonic processes. Early Archean tectonic processes have to be inferred from the rare well-preserved remnants of Archean crust. Models for the formation of Archean crust include large scale mantle melting associated with mantle plumes to generate thick basaltic to ultramafic crust. This crust than undergoes partial melting and internal differentiation to more felsic compositions. The Pilbara craton provides an ideal area for research into the Archean crust, with some of Earth oldest crust being preserved in relatively low strain and low metamorphosed greenstone belts. The volcanic cycles preserved in the greenstone belts of the Paleoarchean East Pilbara Terrane of the Pilbara craton represent the type example of plume-derived volcanism in the early Earth. Here I investigate the lithostratigraphy, volcanology and depositional environment of a volcanic and sedimentary succession ascribed to the Warrawoona group of the East Pilbara Supergroup from the Eastern Warralong Greenstone belt of the East Pilbara Terrane. In addition, I investigate the petrogenesis of well-preserved basaltic samples from the pillow basalt sequence ascribed to the Mt Ada Basalts in the study area. -
Evidence from the Yilgarn and Pilbara Cratons 1 1 2 K.F
Origin of Archean late potassic granites: evidence from the Yilgarn and Pilbara Cratons 1 1 2 K.F. CASSIDY , D.C. CHAMPION AND R.H. SMITHIES 1 Geoscience Australia, Canberra, ACT, kevin.cassidy@doir. wa.gov.au, [email protected] 2 Geological Survey of Western Australia, East Perth, WA, [email protected] Late potassic granites are a characteristic feature of many Archean cratons, including the Yilgarn and Pilbara Cratons in Western Australia. In the Yilgarn Craton, these ‘low Ca’ granites comprise over 20 percent by area of the exposed craton, are distributed throughout the entire craton and intruded at c. 2655–2620 Ma, with no evidence for significant diachroneity at the craton scale. In the Pilbara Craton, similar granites are concentrated in the East Pilbara Terrane, have ages of c. 2890–2850 Ma and truncate domain boundaries. Late potassic granites are dominantly biotite granites but include two mica granites. They are ‘crustally derived’ with high K2O/Na2O, high LILE, LREE, U, Th, variable Y and low CaO, Sr contents. They likely represent dehydration melting of older LILE-rich tonalitic rocks at low to moderate pressures. High HFSE contents suggest high temperature melting, consistent with a water-poor source. Models for their genesis must take into account that: 1. the timing of late potassic granites shows no relationship with earlier transitional-TTG plutonism; 2. there is no relationship to crustal age, with emplacement ranging from c. 100 m.y. (eastern Yilgarn) to c. 800 m.y. (eastern Pilbara) after initial crust formation; 3. the emplacement of late granites reflects a change in tectonic environment, from melting of thickened crust and/or slab for earlier TTG magmatism to melting at higher crustal levels; 4. -
Convective Isolation of Hadean Mantle Reservoirs Through Archean Time
Convective isolation of Hadean mantle reservoirs through Archean time Jonas Tuscha,1, Carsten Münkera, Eric Hasenstaba, Mike Jansena, Chris S. Mariena, Florian Kurzweila, Martin J. Van Kranendonkb,c, Hugh Smithiesd, Wolfgang Maiere, and Dieter Garbe-Schönbergf aInstitut für Geologie und Mineralogie, Universität zu Köln, 50674 Köln, Germany; bSchool of Biological, Earth and Environmental Sciences, The University of New South Wales, Kensington, NSW 2052, Australia; cAustralian Center for Astrobiology, The University of New South Wales, Kensington, NSW 2052, Australia; dDepartment of Mines, Industry Regulations and Safety, Geological Survey of Western Australia, East Perth, WA 6004, Australia; eSchool of Earth and Ocean Sciences, Cardiff University, Cardiff CF10 3AT, United Kingdom; and fInstitut für Geowissenschaften, Universität zu Kiel, 24118 Kiel, Germany Edited by Richard W. Carlson, Carnegie Institution for Science, Washington, DC, and approved November 18, 2020 (received for review June 19, 2020) Although Earth has a convecting mantle, ancient mantle reservoirs anomalies in Eoarchean rocks was interpreted as evidence that that formed within the first 100 Ma of Earth’s history (Hadean these rocks lacked a late veneer component (5). Conversely, the Eon) appear to have been preserved through geologic time. Evi- presence of some late accreted material is required to explain the dence for this is based on small anomalies of isotopes such as elevated abundances of highly siderophile elements (HSEs) in 182W, 142Nd, and 129Xe that are decay products of short-lived nu- Earth’s modern silicate mantle (9). Notably, some Archean rocks clide systems. Studies of such short-lived isotopes have typically with apparent pre-late veneer like 182W isotope excesses were focused on geological units with a limited age range and therefore shown to display HSE concentrations that are indistinguishable only provide snapshots of regional mantle heterogeneities. -
Open Kosei.Pdf
The Pennsylvania State University The Graduate School Department of Geosciences GEOCHEMISTRY OF ARCHEAN–PALEOPROTEROZOIC BLACK SHALES: THE EARLY EVOLUTION OF THE ATMOSPHERE, OCEANS, AND BIOSPHERE A Thesis in Geosciences by Kosei Yamaguchi Copyright 2002 Kosei Yamaguchi Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy May 2002 We approve the thesis of Kosei Yamaguchi Date of Signature ____________________________________ _______________________ Hiroshi Ohmoto Professor of Geochemistry Thesis Advisor Chair of Committee ____________________________________ _______________________ Michael A. Arthur Professor of Geosciences ____________________________________ _______________________ Lee R. Kump Professor of Geosciences ____________________________________ _______________________ Raymond G. Najjar Associate Professor of Meteorology ____________________________________ _______________________ Peter Deines Professor of Geochemistry Associate Head for Graduate Program and Research in Geosciences iii ABSTRACT When did the Earth's surface environment become oxic? The timing and mechanism of the rise of atmospheric pO2 level in the early Precambrian have been long debated but no consensus has been reached. The oxygenation of the atmosphere and oceans has significant impacts on the evolution of the biosphere and the geochemical cycles of redox-sensitive elements. In order to constrain the evolution of the atmosphere, oceans, biosphere, and geochemical cycles of elements, a systematic and multidisciplinary -
Cause of Cambrian Explosion - Terrestrial Or Cosmic?
Progress in Biophysics and Molecular Biology xxx (2018) 1e21 Contents lists available at ScienceDirect Progress in Biophysics and Molecular Biology journal homepage: www.elsevier.com/locate/pbiomolbio Cause of Cambrian Explosion - Terrestrial or Cosmic? * Edward J. Steele a, j, , Shirwan Al-Mufti b, Kenneth A. Augustyn c, Rohana Chandrajith d, John P. Coghlan e, S.G. Coulson b, Sudipto Ghosh f, Mark Gillman g, Reginald M. Gorczynski h, Brig Klyce b, Godfrey Louis i, Kithsiri Mahanama j, Keith R. Oliver k, Julio Padron l, Jiangwen Qu m, John A. Schuster n, W.E. Smith o, Duane P. Snyder b, Julian A. Steele p, Brent J. Stewart a, Robert Temple q, Gensuke Tokoro o, Christopher A. Tout r, Alexander Unzicker s, Milton Wainwright b, j, Jamie Wallis b, Daryl H. Wallis b, Max K. Wallis b, John Wetherall t, D.T. Wickramasinghe u, J.T. Wickramasinghe b, N. Chandra Wickramasinghe b, j, o, Yongsheng Liu v, w a CY O'Connor ERADE Village Foundation, Piara Waters, WA, Australia b Buckingham Centre for Astrobiology, University of Buckingham, UK c Center for the Physics of Living Organisms, Department of Physics, Michigan Technological University, Michigan, United States d Department of Geology, University of Peradeniya, Peradeniya, Sri Lanka e University of Melbourne, Office of the Dean, Faculty Medicine, Dentistry and Health Sciences, 3rd Level, Alan Gilbert Building, Australia f Metallurgical & Materials Engineering IIT, Kanpur, India g South African Brain Research Institute, 6 Campbell Street, Waverly, Johannesburg, South Africa h University Toronto -
Paleontology1
PALEONTOLOGY1 Thoreau’s firm grasp of paleontology laid the groundwork for the climax of WALDEN, which describes the emergence of complexity and beauty from the simple flow of muddy sand at the Deep Cut. It also was the taproot of his lifelong frustration with Christian supernaturalists, who insisted on a fairly brief history of life. Paraphrasing Lyell’s PRINCIPLES, he jested [in A WEEK ON THE C ONCORD AND M ERRIMACK R IVERS]: “It took 100 years to prove that fossils are organic, and 150 more, to prove that they are not to be referred to the Noachian deluge.” Not everyone believes this, even today. Modern “young Earth” creationists still insist that the Elizabethan-era Mosaic chronology of Archbishop Ussher is the correct one, and that we twenty-first century scientists are in error. — Professor Robert M. Thorson, WALDEN’S SHORE, pages 60-1 1. (“Paleology” would be the study of antiques, how much they might fetch at auction.) HDT WHAT? INDEX PALEONTOLOGY PALEONTOLOGY 23,000 BCE Full glacial world, cold and dry; Stage 2 (includes the latest “Glacial Maximum”). This period includes the two ‘coldest phases’ –Heinrich Events– at something like 21,000 BCE-19,000 BCE and at something like 15,000 BCE-12,500 BCE. Music was produced by humans in what is now France; archaeological evidence includes cave paintings, footprints in caves that seem to be those of dancers, and carved bones that seem to be wind and percussion instruments. People made artifacts with primitive geometrical designs. THE WISCONSONIAN GLACIATION “NARRATIVE HISTORY” AMOUNTS TO FABULATION, THE REAL STUFF BEING MERE CHRONOLOGY “Stack of the Artist of Kouroo” Project Paleontology HDT WHAT? INDEX PALEONTOLOGY PALEONTOLOGY 18,000 BCE On the basis of Carbon-14 measurements, this was the last Glacial Maximum, the coldest period of the most recent Ice Age.