Nicholas L. Swanson-Hysell
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Neoproterozoic Glaciations in a Revised Global Palaeogeography from the Breakup of Rodinia to the Assembly of Gondwanaland
Sedimentary Geology 294 (2013) 219–232 Contents lists available at SciVerse ScienceDirect Sedimentary Geology journal homepage: www.elsevier.com/locate/sedgeo Invited review Neoproterozoic glaciations in a revised global palaeogeography from the breakup of Rodinia to the assembly of Gondwanaland Zheng-Xiang Li a,b,⁎, David A.D. Evans b, Galen P. Halverson c,d a ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) and The Institute for Geoscience Research (TIGeR), Department of Applied Geology, Curtin University, GPO Box U1987, Perth, WA 6845, Australia b Department of Geology and Geophysics, Yale University, New Haven, CT 06520-8109, USA c Earth & Planetary Sciences/GEOTOP, McGill University, 3450 University St., Montreal, Quebec H3A0E8, Canada d Tectonics, Resources and Exploration (TRaX), School of Earth and Environmental Sciences, University of Adelaide, SA 5005, Australia article info abstract Article history: This review paper presents a set of revised global palaeogeographic maps for the 825–540 Ma interval using Received 6 January 2013 the latest palaeomagnetic data, along with lithological information for Neoproterozoic sedimentary basins. Received in revised form 24 May 2013 These maps form the basis for an examination of the relationships between known glacial deposits, Accepted 28 May 2013 palaeolatitude, positions of continental rifting, relative sea-level changes, and major global tectonic events Available online 5 June 2013 such as supercontinent assembly, breakup and superplume events. This analysis reveals several fundamental ’ Editor: J. Knight palaeogeographic features that will help inform and constrain models for Earth s climatic and geodynamic evolution during the Neoproterozoic. First, glacial deposits at or near sea level appear to extend from high Keywords: latitudes into the deep tropics for all three Neoproterozoic ice ages (Sturtian, Marinoan and Gaskiers), al- Neoproterozoic though the Gaskiers interval remains very poorly constrained in both palaeomagnetic data and global Rodinia lithostratigraphic correlations. -
A Community Effort Towards an Improved Geological Time Scale
A community effort towards an improved geological time scale 1 This manuscript is a preprint of a paper that was submitted for publication in Journal 2 of the Geological Society. Please note that the manuscript is now formally accepted 3 for publication in JGS and has the doi number: 4 5 https://doi.org/10.1144/jgs2020-222 6 7 The final version of this manuscript will be available via the ‘Peer reviewed Publication 8 DOI’ link on the right-hand side of this webpage. Please feel free to contact any of the 9 authors. We welcome feedback on this community effort to produce a framework for 10 future rock record-based subdivision of the pre-Cryogenian geological timescale. 11 1 A community effort towards an improved geological time scale 12 Towards a new geological time scale: A template for improved rock-based subdivision of 13 pre-Cryogenian time 14 15 Graham A. Shields1*, Robin A. Strachan2, Susannah M. Porter3, Galen P. Halverson4, Francis A. 16 Macdonald3, Kenneth A. Plumb5, Carlos J. de Alvarenga6, Dhiraj M. Banerjee7, Andrey Bekker8, 17 Wouter Bleeker9, Alexander Brasier10, Partha P. Chakraborty7, Alan S. Collins11, Kent Condie12, 18 Kaushik Das13, Evans, D.A.D.14, Richard Ernst15, Anthony E. Fallick16, Hartwig Frimmel17, Reinhardt 19 Fuck6, Paul F. Hoffman18, Balz S. Kamber19, Anton Kuznetsov20, Ross Mitchell21, Daniel G. Poiré22, 20 Simon W. Poulton23, Robert Riding24, Mukund Sharma25, Craig Storey2, Eva Stueeken26, Rosalie 21 Tostevin27, Elizabeth Turner28, Shuhai Xiao29, Shuanhong Zhang30, Ying Zhou1, Maoyan Zhu31 22 23 1Department -
The History of Ice on Earth by Michael Marshall
The history of ice on Earth By Michael Marshall Primitive humans, clad in animal skins, trekking across vast expanses of ice in a desperate search to find food. That’s the image that comes to mind when most of us think about an ice age. But in fact there have been many ice ages, most of them long before humans made their first appearance. And the familiar picture of an ice age is of a comparatively mild one: others were so severe that the entire Earth froze over, for tens or even hundreds of millions of years. In fact, the planet seems to have three main settings: “greenhouse”, when tropical temperatures extend to the polesand there are no ice sheets at all; “icehouse”, when there is some permanent ice, although its extent varies greatly; and “snowball”, in which the planet’s entire surface is frozen over. Why the ice periodically advances – and why it retreats again – is a mystery that glaciologists have only just started to unravel. Here’s our recap of all the back and forth they’re trying to explain. Snowball Earth 2.4 to 2.1 billion years ago The Huronian glaciation is the oldest ice age we know about. The Earth was just over 2 billion years old, and home only to unicellular life-forms. The early stages of the Huronian, from 2.4 to 2.3 billion years ago, seem to have been particularly severe, with the entire planet frozen over in the first “snowball Earth”. This may have been triggered by a 250-million-year lull in volcanic activity, which would have meant less carbon dioxide being pumped into the atmosphere, and a reduced greenhouse effect. -
Timing and Tempo of the Great Oxidation Event
Timing and tempo of the Great Oxidation Event Ashley P. Gumsleya,1, Kevin R. Chamberlainb,c, Wouter Bleekerd, Ulf Söderlunda,e, Michiel O. de Kockf, Emilie R. Larssona, and Andrey Bekkerg,f aDepartment of Geology, Lund University, Lund 223 62, Sweden; bDepartment of Geology and Geophysics, University of Wyoming, Laramie, WY 82071; cFaculty of Geology and Geography, Tomsk State University, Tomsk 634050, Russia; dGeological Survey of Canada, Ottawa, ON K1A 0E8, Canada; eDepartment of Geosciences, Swedish Museum of Natural History, Stockholm 104 05, Sweden; fDepartment of Geology, University of Johannesburg, Auckland Park 2006, South Africa; and gDepartment of Earth Sciences, University of California, Riverside, CA 92521 Edited by Mark H. Thiemens, University of California, San Diego, La Jolla, CA, and approved December 27, 2016 (received for review June 11, 2016) The first significant buildup in atmospheric oxygen, the Great situ secondary ion mass spectrometry (SIMS) on microbaddeleyite Oxidation Event (GOE), began in the early Paleoproterozoic in grains coupled with precise isotope dilution thermal ionization association with global glaciations and continued until the end of mass spectrometry (ID-TIMS) and paleomagnetic studies, we re- the Lomagundi carbon isotope excursion ca. 2,060 Ma. The exact solve these uncertainties by obtaining accurate and precise ages timing of and relationships among these events are debated for the volcanic Ongeluk Formation and related intrusions in because of poor age constraints and contradictory stratigraphic South Africa. These ages lead to a more coherent global per- correlations. Here, we show that the first Paleoproterozoic global spective on the timing and tempo of the GOE and associated glaciation and the onset of the GOE occurred between ca. -
The Arc of the Snowball: U-Pb Dates Constrain the Islay Anomaly and the Initiation of the Sturtian Glaciation
The arc of the Snowball: U-Pb dates constrain the Islay anomaly and the initiation of the Sturtian glaciation Scott MacLennan1, Yuem Park2, Nicholas Swanson-Hysell2, Adam Maloof1, Blair Schoene1, Mulubrhan Gebreslassie3, Eliel Antilla2, Tadele Tesema3, Mulugeta Alene3, and Bereket Haileab4 1Department of Geosciences, Princeton University, Princeton, New Jersey 08544, USA 2Earth and Planetary Sciences Department, University of California, Berkeley, California 94720, USA 3School of Earth Sciences, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia 4Department of Geology, Carleton College, Northfield, Minnesota 55057, USA ABSTRACT Models for the mechanisms driving Sturtian Snowball initiation In order to understand the onset of Snowball Earth events, pre- include enhanced organic production and remineralization under anaer- cise geochronology and chemostratigraphy are needed on complete obic conditions (Tziperman et al., 2011), increased CO2 sequestration sections leading into the glaciations. While deposits associated with through weathering of large volumes of mafic extrusions at equatorial lati- the Neoproterozoic Sturtian glaciation have been found on nearly tudes (Goddéris et al., 2003; Macdonald et al., 2010), and sulfate injection every continent, time-calibrated stratigraphic sections that record into the stratosphere caused by equatorial basaltic eruptions (Macdonald paleoenvironmental conditions leading into the glaciation are exceed- and Wordsworth, 2017). Regardless of the initiation mechanism, once ice ingly rare. Instead, the transition to glaciation is normally expressed sheet extent reaches ~30° of latitude, numerical models predict that ice as erosive contacts with overlying diamictites, and the best existing expansion to the equator should occur over thousands of years due to the geochronological constraints come from volcanic successions with ice albedo feedback (Baum and Crowley, 2001). -
Predominantly Ferruginous Conditions in South China During
Article Predominantly Ferruginous Conditions in South China during the Marinoan Glaciation: Insight from REE Geochemistry of the Syn‐glacial Dolostone from the Nantuo Formation in Guizhou Province, China Shangyi Gu 1,*, Yong Fu 1 and Jianxi Long 2 1 College of Resource and Environmental Engineering, Guizhou University, Guiyang 550025, China; [email protected] 2 Guizhou Geological Survey, Bureau of Geology and Mineral Exploration and Development of Guizhou Province, Guiyang 550081, China; with‐[email protected] * Correspondence: [email protected]; Tel.: +86‐0851‐83627126 Received: 23 April 2019; Accepted: 3 June 2019; Published: 5 June 2019 Abstract: The Neoproterozoic Era witnessed two low‐latitude glaciations, which exerted a fundamental influence on ocean‒atmosphere redox conditions and biogeochemical cycling. Climate models and palaeobiological evidence support the belief that open waters provided oases for life that survived snowball Earth glaciations, yet independent geochemical evidence for marine redox conditions during the Marinoan glaciation remains scarce owing to the apparent lack of primary marine precipitates. In this study, we explore variability in rare earth elements (REEs) and trace metal concentrations in dolostone samples of the Cryogenian Nantuo Formation taken from a drill core in South China. Petrological evidence suggests that the dolostone in the Nantuo Formation was formed in near‐shore waters. All the examined dolostone samples featured significant enrichment of manganese (345‒10,890 ppm, average 3488 ppm) and middle rare earth elements (MREEs) (Bell Shape Index: 1.43‒2.16, average 1.76) after being normalized to Post‐Archean Australian Shale (PAAS). Most dolostone samples showed slight to no negative Ce anomalies (Ce*/Ce 0.53‒1.30, average 0.95), as well as positive Eu anomalies (Eu*/Eu 1.77‒3.28, average 1.95). -
2019 AGU Section Awardees and Named Lecturers - Eos 8/1/19, 3 59 PM
2019 AGU Section Awardees and Named Lecturers - Eos 8/1/19, 359 PM 2019 AGU Section Awardees and Named Lecturers Eighty-two distinguished scientists receive accolades from groups representing their disciplines within AGU, the world’s largest Earth and space science society. By Robin Bell and Mary Anne Holmes ! 31 July 2019 The 2019 section awardees and named lecturers have been selected, and AGU staff, leaders, and selection committees wholeheartedly congratulate these awardees! Our colleagues have been selected for these prestigious honors for their sustained and unique contributions to advancing our understanding of Earth, its atmosphere and oceans, and planets and astral bodies beyond our own. The sciences encompassed by AGU are crucial for the health and well-being of our planet’s inhabitants. These awardees have contributed to both that understanding and the planetary health and well-being through their scientific advancements and outstanding service to the science and to AGU. https://eos.org/agu-news/2019-agu-section-awardees-and-named-lecturers Page 1 of 7 2019 AGU Section Awardees and Named Lecturers - Eos 8/1/19, 359 PM This year’s cohort of awardees reflects the diversity that is integral to the Earth and space sciences. Among the 25 sections of AGU there are 65 such awards; 21 are for early- career scientists (up to 10 years post-Ph.D.) and 6 are for midcareer (10 to 20 years post-Ph.D.). Twenty-seven awards provide named lectureships that offer unique opportunities to highlight the meritorious accomplishments of the awardees. AGU inaugurated the Bowie Lecture in 1989 to commemorate the 50th presentation of the William Bowie Medal, which is named for AGU’s first president and is the highest honor given by the organization. -
Bibliography of Precambrian Glaciation (1871 to Present) (Total; Pprot-Archean; Ediacaran; Cryogenian; Geophys.; Geochem.; Geobiol.; Geol.)
Bibliography of Precambrian Glaciation (1871 to present) (Total; PProt-Archean; Ediacaran; Cryogenian; Geophys.; Geochem.; Geobiol.; Geol.) 2020: 16 3 1 12 1 4 6 Burzinski, G., Dececchi, T.A., Narbonne, G.M., Dalrymple, R.W. 2020. Cryogenian Aspidella from northwestern Canada. Precambrian Research 000, 000-000. Del Cortona, A., Jackson, C.J., Bucchini, F., Van Bel, M., D’hondt, S., Škaloud, P., Delwiche, C.F., Knoll, A.H., Raven, J.A., Verbruggen, H., Vandepoele, K., De Clerck, O., Leliaert, F. 2020. Neoproterozoic origin and multiple transitions to macroscopic growth in green seaweeds. Proceedings of the National Academy of Sciences 117, 2551-2559. Erickson, T.M., Kirkland, C.L., Timms, N.E., Cavosie, A.J., Davison, T.M. 2020. Precise radiometric age establishes Yarrabubba, Western Australia, as Earth’s oldest recognized meteorite impact structure. Nature Communications 00, 000-000. Hallmann, C., Nettersheim, B.J., Brocks, J.J., Schwelm, A., Hope, J.M., Not, F., Lomas, M., Schmidt, C., Schiebel, R., Nowack, E.C.M., De Decker, P., Pawlowski, J., Bowser, S.S., Bobrowskiy, I., Zonneveld, K., Stuhr, M. 2020. Reply to: Sources of C30 steroid biomarkers in Neoproterozoic-Cambrian rocks and oils. Nature Ecology & Evolution 4, 37-39. Hiatt, E.E., Pufahl, P.K., Guimarães da Silva, L. 2020. Iron and phosphorus biochamical systems and the Cryogenian−Ediacaran transition, Jacadigo basin, Brazil: Implications for the Neoproterozoic Oxygenation Event. Precambrian Research 337, 105533. Lan, Z.W., Huyskens, M.H., Lu, K., Li, X.H., Zhang, G.Y., Lu, D.B., Yin, Q.Z. 2020. Toward refining the onset age of Sturtian glaciation in South China. -
Svalbard Marinoan and Sturtian Glacial Suites Marked by Contrasting Sulfate Multi- Isotope Compositions HUIMING BAO1, IAN J
Goldschmidt Conference Abstracts 155 Svalbard Marinoan and Sturtian glacial suites marked by contrasting sulfate multi- isotope compositions HUIMING BAO1, IAN J. FAIRCHILD2, PETER M. WYNN3 1 Department of Geology & Geophysics, Louisiana State University, Baton Rouge, Louisiana, U.S.A. 2 School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK 3 Lancaster Environment Centre, University of Lancaster, Lancaster, UK Two episodes of panglaciation, the Sturtian and Marinoan, are generally recognized in the Cryogenian Period (720 to 635 Ma) of the Neoproterozoic Era of the Earth history worldwide. One of the most pronounced features of the Marinoan glacial packages has been the occurrence of distinct non- mass-dependent 17O depletion in barite sulfate and/or carbonate-associated sulfate (CAS). Since the Marinoan 17O depletion (MOSD) has so far been identified in most Marinoan glacial deposits, MOSD has essentially become a marker for Marinoan glacial deposits. However, if the Sturtian glaciation behaved the same way as the Marinoan one in that the “Snowball Earth” was also melt back owing to an ultra-high pCO2, we should expect to pick up a corresponding Sturtian 17O depletion or SOSD signature as well. Unfortunately, we currently do not have a reference section to test this hypothesis. In the classic Neoproterozoic sections of NE Spitsbergen, Svalbard, occurrence of both the Sturtian and Marinoan glacial packages have been supported by an array of evidence. Importantly, due to its continental or close-to-continent deposition setting throughout the Cryogenian, Svalbard should be the most likely place to preserve SOSD if there was one. Here we present a set of δ34S-δ18O-∆17O data triplets for CAS traversing the entire Cryogenian sedimentary sequence, including the Elbobreen (E1, E2, E3, and E4), Wilsonbreen (W1, W2, and W3), and Dracoisen (D1, D2, and D3) formations. -
Dennis V. Kent
Dennis Kent cv December 2020 p. 1 DENNIS V. KENT Paleomagnetics Laboratory Lamont-Doherty Earth Observatory of Columbia University Palisades, NY 10964-8000 USA [email protected] EDUCATION 1974 Ph.D. (Marine Geology & Geophysics) Columbia University, NY 1968 B.S. (Geology) City College of New York, NY APPOINTMENTS 2020– Board of Governor Professor Emeritus, Rutgers University 2007–2020 Board of Governor Professor, Rutgers University 2003 Gastprofessor, Institüt für Geophysik, ETH, Zürich (also in 1982 and 1987) 2003 Visiting Scholar, Scripps Institution of Oceanography, UCSD, La Jolla, CA 1998–2007 Distinguished Professor, Department of Earth & Planetary Sciences, Rutgers University 1998– Adjunct Senior Research Scientist, Lamont-Doherty Earth Observatory 1993 Director of Research, Lamont-Doherty Earth Observatory 1989–90 Interim Director, Lamont-Doherty Earth Observatory 1987–89 Associate Director for Oceans & Climate, Lamont-Doherty Earth Observatory 1987–98 Adjunct Professor, Dept. of Earth & Environmental Sciences, Columbia University 1984–99 Doherty Senior Scientist, Lamont-Doherty Earth Observatory 1981–87 Adjunct Associate Professor, Dept. of Geological Sciences, Columbia University 1979–84 Senior Research Scientist, Lamont-Doherty Earth Observatory 1974–79 Research Associate, Lamont-Doherty Earth Observatory, Columbia University PRINCIPAL RESEARCH INTERESTS Paleomagnetism, geomagnetism, rock magnetism and their application to geologic problems. Current interests include astrochronometric polarity time scales; paleogeography, paleoclimatology and the long-term carbon cycle; paleointensity; magnetic properties of sediments and polar ice. HONORS Fellow of the American Academy of Arts and Sciences (2012) Arduino Lecture, University of Padova (2010) William Gilbert Award, American Geophysical Union (2009) Petrus Peregrinus Medal, European Geosciences Union (2006) Docteur honoris causa, Sorbonne, Universities of Paris-IPGP (2005) Member of the U.S. -
Appendices Due to Concerns Over the Quality of the Data Collected
APPENDIX A WSU 2014-19 STRATEGIC PLAN Appendix A: WSU Strategic Plan 2014-15 Strategic Plan 2014-2019 President Elson S. Floyd, Ph.D. Strategic Plan 2014-2019 Introduction The 2014-19 strategic plan builds on the previous five-year plan, recognizing the core values and broad mission of Washington State University. Goals and strategies were developed to achieve significant progress toward WSU’s aspiration of becoming one of the nation’s leading land-grant universities, preeminent in research and discovery, teaching, and engagement. The plan emphasizes the institution’s unique role as an accessible, approachable research institution that provides opportunities to an especially broad array of students while serving Washington state’s broad portfolio of social and economic needs. While providing exceptional leadership in traditional land-grant disciplines, Washington State University adds value as an integrative partner for problem solving due to its innovative focus on applications and its breadth of program excellence. The plan explicitly recognizes the dramatic changes in public funding that have occurred over the duration of the previous strategic plan, along with the need for greater institutional nimbleness, openness, and entrepreneurial activity that diversifies the University’s funding portfolio. In addition, the plan reaffirms WSU’s land-grant mission by focusing greater attention system-wide on increasing access to educational opportunity, responding to the needs of Washington state through research, instruction, and outreach, and contributing to economic development and public policy. While the new plan retains the four key themes of the previous plan, its two central foci include offering a truly transformative educational experience to undergraduate and graduate students and accelerating the development of a preeminent research portfolio. -
Snowball Earth
Snowball Earth The Snowball Earth hypothesis proposes that during one or more of Earth's icehouse climates, Proterozoic snowball periods (millions of years) Earth's surface became entirely or nearly entirely Baykonurian frozen, sometime earlier than 650 Mya (million -550 — years ago) during the Cryogenian period. – ← Gaskiers Proponents of the hypothesis argue that it best -600 — explains sedimentary deposits generally regarded Ediacaran as of glacial origin at tropical palaeolatitudes and – other enigmatic features in the geological record. Marinoan[1] -650 — Opponents of the hypothesis contest the implications of the geological evidence for global – Cryogenian Sturtian[1] glaciation and the geophysical feasibility of an -700 — ice- or slush-covered ocean[3][4] and emphasize the difficulty of escaping an all-frozen condition. – A number of unanswered questions remain, -750 — Kaigas? including whether the Earth was a full snowball, – or a "slushball" with a thin equatorial band of open (or seasonally open) water. -800 — The snowball-Earth episodes are proposed to have – occurred before the sudden radiation of -850 — multicellular bioforms, known as the Cambrian Tonian – explosion. The most recent snowball episode may have triggered the evolution of multicellularity. -900 — Another, much earlier and longer snowball – episode, the Huronian glaciation, which would have occurred 2400 to 2100 Mya, may have been -950 — triggered by the first appearance of oxygen in the – atmosphere, the "Great Oxygenation Event". -1000 — Neoproterozoic era Snowball Earth Estimate of Proterozoic glacial periods.[2][1] Contents Dating of pre-Gaskiers glaciations is History uncertain. As for the Kaigas, its very existence is doubted by some. An earlier and Evidence for ancient glaciation mounts longer possible snowball phase, the Huronian Global glaciation proposed glaciation, is not shown.