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Atlantic Constrain Laurentide Ice Sheet Extent During Marine Isotope Stage 3
Sea-level records from the U.S. mid- Atlantic constrain Laurentide Ice Sheet extent during Marine Isotope Stage 3 The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Pico, T, J. R. Creveling, and J. X. Mitrovica. 2017. “Sea-level records from the U.S. mid-Atlantic constrain Laurentide Ice Sheet extent during Marine Isotope Stage 3.” Nature Communications 8 (1): 15612. doi:10.1038/ncomms15612. http://dx.doi.org/10.1038/ ncomms15612. Published Version doi:10.1038/ncomms15612 Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:33490941 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA ARTICLE Received 7 Dec 2016 | Accepted 11 Apr 2017 | Published 30 May 2017 DOI: 10.1038/ncomms15612 OPEN Sea-level records from the U.S. mid-Atlantic constrain Laurentide Ice Sheet extent during Marine Isotope Stage 3 T. Pico1, J.R. Creveling2 & J.X. Mitrovica1 The U.S. mid-Atlantic sea-level record is sensitive to the history of the Laurentide Ice Sheet as the coastline lies along the ice sheet’s peripheral bulge. However, paleo sea-level markers on the present-day shoreline of Virginia and North Carolina dated to Marine Isotope Stage (MIS) 3, from 50 to 35 ka, are surprisingly high for this glacial interval, and remain unexplained by previous models of ice age adjustment or other local (for example, tectonic) effects. -
Circum-Indian Ocean Hydroclimate at the Mid to Late Holocene Transition: the Double Drought Hypothesis and Consequences for the Harappan” by Nick Scroxton Et Al
Clim. Past Discuss., https://doi.org/10.5194/cp-2020-138-RC2, 2021 CPD © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. Interactive comment Interactive comment on “Circum-Indian ocean hydroclimate at the mid to late Holocene transition: The Double Drought hypothesis and consequences for the Harappan” by Nick Scroxton et al. Harvey Weiss (Referee) [email protected] Received and published: 4 January 2021 Global KM-A Congruence and the Indus Collapse Harvey Weiss Printer-friendly version Department of Near Eastern Languages and Civilizations, Environmental Studies Pro- gram, and School of Environment, Yale University Discussion paper The IUGS-recognized global boundary stratotype for the 4.2 - 3.9 ka BP event, marking C1 the middle to late Holocene transition to the Meghalayan stage, is the KM-A speleothem δ18O record from Mawmluh Cave, Meghalaya, NW India, that is an Indian Summer CPD Monsoon (ISM) drought record (Berkelhammer et al 2012; Walker et al 2019). The recent analysis of the Indus delta foraminifera record at core 63KA has identified, as well, the Indian Winter Monsoon drought synchronous with the 4.2 ka BP ISM drought Interactive (Giesche et al 2019). The global boundary sub-stratotype is the Mt. Logan Yukon comment glacial core’s δ18O moisture event (Fisher et al 2008). Scroxton et al present a principal components analysis of seven recent δ18O speleothem records from the Indian Ocean region and the Giesche et al 2019 delta foraminifera analyses (line 110) “to investigate the impacts of the 4.2 kyr event on trop- ical Indian Ocean basin monsoonal rainfall” and the late third millennium BC Indus urban collapses. -
R~;: PHYSIOLOGICAL, MIGRATORIAL
....----------- 'r~;: i ! 'r; Pa/eont .. 62(4), 1988, pp. 64~52 Copyright © 1988, The Paleontological Society 0022-3360/88/0062-0640$03.00 PHYSIOLOGICAL, MIGRATORIAL, CLIMATOLOGICAL, GEOPHYSICAL, SURVIVAL, AND EVOLUTIONARY IMPLICATIONS OF CRETACEOUS POLAR DINOSAURS GREGORY S. PAUL 3109 North Calvert Street, Baltimore, Maryland 21218 ABSTRACTT- he presence of Late Cretaceous social dinosaurs in polar regions confronted them with winter conditions of extended dark, coolness, breezes, and precipitation that could best be coped with via an endothermic homeothermic physiology of at least the tenrec level. This is true whether the dinosaurs stayed year round in the polar regime-which in North America extended from Alaska south to Montana-or if they migrated away from polar winters. More reptilian physiologies fail to meet the demands of such winters -in certain key ways, a· point tentatively confirmed by the apparent failure of giant Late Cretaceous phobosuchid crocodilians to dwell north of Montana. Low metabolisms were also insufficient for extended annual migrations away from and towards the poles. It is shown that even high metabolic rate dinosaurs probably remained in their polar habitats year-round. The possibility that dinosaurs had avian-mammalian metabolic systems, and may have borne insulation at least seasonally, severely limits their use as polar paleoclimatic and Earth axial tilt indicators. Polar dinosaurs may have been a center of dinosaur evolution. The possible ability of polar dinosaurs to cope with conditions of cool and dark challenges theories that a gradual temperature decline, or a sudden, meteoritic or volcanic induced collapse in temperature and sunlight, destroyed the dinosaurs. INTRODUCTION America suggests that dinosaurs were regularly crossing, and NCREASINGNUMBERSof remains show that dinosaurs lived living upon, the Bering Land Bridge within a few degrees of the I near the North and South Poles during the Cretaceous. -
The Easternmost Occurrence of Mammut Pacificus (Proboscidea: Mammutidae), Based on a Partial Skull from Eastern Montana, USA
The easternmost occurrence of Mammut pacificus (Proboscidea: Mammutidae), based on a partial skull from eastern Montana, USA Andrew T. McDonald1, Amy L. Atwater2, Alton C. Dooley Jr1 and Charlotte J.H. Hohman2,3 1 Western Science Center, Hemet, CA, United States of America 2 Museum of the Rockies, Montana State University, Bozeman, MT, United States of America 3 Department of Earth Sciences, Montana State University, Bozeman, MT, United States of America ABSTRACT Mammut pacificus is a recently described species of mastodon from the Pleistocene of California and Idaho. We report the easternmost occurrence of this taxon based upon the palate with right and left M3 of an adult male from the Irvingtonian of eastern Montana. The undamaged right M3 exhibits the extreme narrowness that characterizes M. pacificus rather than M. americanum. The Montana specimen dates to an interglacial interval between pre-Illinoian and Illinoian glaciation, perhaps indicating that M. pacificus was extirpated in the region due to habitat shifts associated with glacial encroachment. Subjects Biogeography, Evolutionary Studies, Paleontology, Zoology Keywords Mammut pacificus, Mammutidae, Montana, Irvingtonian, Pleistocene INTRODUCTION Submitted 7 May 2020 The recent recognition of the Pacific mastodon (Mammut pacificus (Dooley Jr et al., 2019)) Accepted 3 September 2020 as a new species distinct from and contemporaneous with the American mastodon Published 16 November 2020 (M. americanum) revealed an unrealized complexity in North American mammutid Corresponding author evolution during the Pleistocene. Dooley Jr et al. (2019) distinguished M. pacificus from Andrew T. McDonald, [email protected] M. americanum by a suite of dental and skeletal features: (1) upper third molars (M3) Academic editor and lower third molars (m3) much narrower relative to length in M. -
A Possible Late Pleistocene Impact Crater in Central North America and Its Relation to the Younger Dryas Stadial
A POSSIBLE LATE PLEISTOCENE IMPACT CRATER IN CENTRAL NORTH AMERICA AND ITS RELATION TO THE YOUNGER DRYAS STADIAL SUBMITTED TO THE FACULTY OF THE UNIVERSITY OF MINNESOTA BY David Tovar Rodriguez IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE Howard Mooers, Advisor August 2020 2020 David Tovar All Rights Reserved ACKNOWLEDGEMENTS I would like to thank my advisor Dr. Howard Mooers for his permanent support, my family, and my friends. i Abstract The causes that started the Younger Dryas (YD) event remain hotly debated. Studies indicate that the drainage of Lake Agassiz into the North Atlantic Ocean and south through the Mississippi River caused a considerable change in oceanic thermal currents, thus producing a decrease in global temperature. Other studies indicate that perhaps the impact of an extraterrestrial body (asteroid fragment) could have impacted the Earth 12.9 ky BP ago, triggering a series of events that caused global temperature drop. The presence of high concentrations of iridium, charcoal, fullerenes, and molten glass, considered by-products of extraterrestrial impacts, have been reported in sediments of the same age; however, there is no impact structure identified so far. In this work, the Roseau structure's geomorphological features are analyzed in detail to determine if impacted layers with plastic deformation located between hard rocks and a thin layer of water might explain the particular shape of the studied structure. Geophysical data of the study area do not show gravimetric anomalies related to a possible impact structure. One hypothesis developed on this works is related to the structure's shape might be explained by atmospheric explosions dynamics due to the disintegration of material when it comes into contact with the atmosphere. -
Article Processing Charges for This Open-Access Depth, Rendering Deeper and Older OM Bioavailable for Mi- Publication Were Covered by a Research Crobial Decomposition
Biogeosciences, 15, 1969–1985, 2018 https://doi.org/10.5194/bg-15-1969-2018 © Author(s) 2018. This work is distributed under the Creative Commons Attribution 3.0 License. Substrate potential of last interglacial to Holocene permafrost organic matter for future microbial greenhouse gas production Janina G. Stapel1, Georg Schwamborn2, Lutz Schirrmeister2, Brian Horsfield1, and Kai Mangelsdorf1 1GFZ, German Research Centre for Geoscience, Helmholtz Centre Potsdam, Organic Geochemistry, Telegrafenberg, 14473 Potsdam, Germany 2Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Department of Periglacial Research, Telegrafenberg, A43, 14473 Potsdam, Germany Correspondence: Kai Mangelsdorf ([email protected]) Received: 14 March 2017 – Discussion started: 17 March 2017 Revised: 2 February 2018 – Accepted: 6 February 2018 – Published: 4 April 2018 Abstract. In this study the organic matter (OM) in sev- 1 Introduction eral permafrost cores from Bol’shoy Lyakhovsky Island in NE Siberia was investigated. In the context of the observed The northern areas of the Eurasian landmass are under- global warming the aim was to evaluate the potential of lain by permafrost, which is defined as ground that remains freeze-locked OM from different depositional ages to act as colder than 0 ◦C for at least 2 consecutive years (Washburn, a substrate provider for microbial production of greenhouse 1980). These areas contain a large reservoir of organic car- gases from thawing permafrost. To assess this potential, the bon freeze-locked in the permafrost deposits (French, 2007; concentrations of free and bound acetate, which form an Zimov et al., 2009). Hugelius et al. (2014) estimated that appropriate substrate for methanogenesis, were determined. -
Formal Ratification of the Subdivision of the Holocene Series/ Epoch
Article 1 by Mike Walker1*, Martin J. Head 2, Max Berkelhammer3, Svante Björck4, Hai Cheng5, Les Cwynar6, David Fisher7, Vasilios Gkinis8, Antony Long9, John Lowe10, Rewi Newnham11, Sune Olander Rasmussen8, and Harvey Weiss12 Formal ratification of the subdivision of the Holocene Series/ Epoch (Quaternary System/Period): two new Global Boundary Stratotype Sections and Points (GSSPs) and three new stages/ subseries 1 School of Archaeology, History and Anthropology, Trinity Saint David, University of Wales, Lampeter, Wales SA48 7EJ, UK; Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, Wales SY23 3DB, UK; *Corresponding author, E-mail: [email protected] 2 Department of Earth Sciences, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario LS2 3A1, Canada 3 Department of Earth and Environmental Sciences, University of Illinois, Chicago, Illinois 60607, USA 4 GeoBiosphere Science Centre, Quaternary Sciences, Lund University, Sölveg 12, SE-22362, Lund, Sweden 5 Institute of Global Change, Xi’an Jiaotong University, Xian, Shaanxi 710049, China; Department of Earth Sciences, University of Minne- sota, Minneapolis, MN 55455, USA 6 Department of Biology, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada 7 Department of Earth Sciences, University of Ottawa, Ottawa K1N 615, Canada 8 Centre for Ice and Climate, The Niels Bohr Institute, University of Copenhagen, Julian Maries Vej 30, DK-2100, Copenhagen, Denmark 9 Department of Geography, Durham University, Durham DH1 3LE, UK 10 -
Regional Disparity in Summer Monsoon Precipitation in the Indian Subcontinent During Northgrippian to Meghalayan Transition
REVIEW ARTICLES Regional disparity in summer monsoon precipitation in the Indian subcontinent during Northgrippian to Meghalayan transition Som Dutt1,*, Anil K. Gupta2, Rahul Devrani1, Ram R. Yadav1 and Raj K. Singh3 1Wadia Institute of Himalayan Geology, 33, General Mahadeo Singh Road, Dehradun 248 001, India 2Department of Geology and Geophysics, Indian Institute of Technology, Kharagpur 721 302, India 3School of Earth, Ocean and Climate Sciences, Indian Institute of Technology Bhubaneswar, Argul 752 050, India soon domain1–6,8–15. Detailed reviews on ISM variability The present study reveals distinct spatial variability of 1,2 summer monsoon precipitation in Indian subcontinent during Holocene are available , but regional precipita- during Northgrippian to Meghalayan transition. Pro- tion disparity in Indian subcontinent during the 4.2 ka tracted dry phase lasting ~1000 yrs was observed event is not much discussed. Here, we examined availa- ~4.2 ka BP in southern and northwestern India whereas ble marine and terrestrial proxy records of ISM variabi- 200–300 yrs event occurred in northeastern parts. lity from different regions in Indian subcontinent and Strong El Niño conditions beginning ~4.3 kyr BP were northern Indian Ocean (IO) for better understandings of associated with the millennial long dryness in western precipitation variability during Northgrippian to Megha- parts but its influence was limited in the eastern layan transition. region. Cross-verified, high-resolution records from different geographic regions of India are still required to ascertain if regional differences occurred in span Domain of ISM and magnitude during Northgrippian to Meghalayan transition. ISM precipitation is pivotal for socio-economic wellbeing of 1/3rd of human population living in Indian subconti- Keywords: Indian summer monsoon, Indus civilization, nent. -
Sedimentological-Geochemical Data Based Reconstruction of Climate
quaternary Article Sedimentological-Geochemical Data Based Reconstruction of Climate Changes and Human Impacts from the Peat Sequence of Round Lake in the Western Foothill Area of the Eastern Carpathians, Romania Réka Orsolya Tapody 1,Pál Sümegi 1,*, Dávid Molnár 1 ,Máté Karlik 2,3, Tünde Tör˝ocsik 1,Péter Cseh 1 and László Makó 1 1 Department of Geology and Palaeontology, University of Szeged, Egyetem Str. 2-6, H-6722 Szeged, Hungary; [email protected] (R.O.T.); [email protected] (D.M.); [email protected] (T.T.); [email protected] (P.C.); [email protected] (L.M.) 2 Isotope Climatology and Environmental Research Centre, Institute for Nuclear Research, Bem Square 18/c, H-4026 Debrecen, Hungary; [email protected] 3 Institute for Geological and Geochemical Research, RCAES, Budaörsi Str. 45, H-1112 Budapest, Hungary * Correspondence: [email protected] Abstract: This paper presents the results of comparative sedimentological and geochemical analysis of the mire at Sânpaul, Round Lake (Kerek-tó). The palaeoecological site is situated in the western Citation: Tapody, R.O.; Sümegi, P.; foothill area of the Eastern Carpathians in Romania. The primary objective of this study was to Molnár, D.; Karlik, M.; Tör˝ocsik,T.; analyse the accumulation of major and trace elements in a 7500 year-long peat and lake deposition. Cseh, P.; Makó, L. The concentrations of 13 elements were determined by using handheld XRF. This paper presents Sedimentological-Geochemical Data the results of a multidisciplinary study, for which the principal aims were to examine the long- Based Reconstruction of Climate term relationship between land degradation in the Homoród Hills using various palaeoecological Changes and Human Impacts from techniques, primarily comparative geochemical analyses. -
International Chronostratigraphic Chart
INTERNATIONAL CHRONOSTRATIGRAPHIC CHART www.stratigraphy.org International Commission on Stratigraphy v 2018/08 numerical numerical numerical Eonothem numerical Series / Epoch Stage / Age Series / Epoch Stage / Age Series / Epoch Stage / Age GSSP GSSP GSSP GSSP EonothemErathem / Eon System / Era / Period age (Ma) EonothemErathem / Eon System/ Era / Period age (Ma) EonothemErathem / Eon System/ Era / Period age (Ma) / Eon Erathem / Era System / Period GSSA age (Ma) present ~ 145.0 358.9 ± 0.4 541.0 ±1.0 U/L Meghalayan 0.0042 Holocene M Northgrippian 0.0082 Tithonian Ediacaran L/E Greenlandian 152.1 ±0.9 ~ 635 Upper 0.0117 Famennian Neo- 0.126 Upper Kimmeridgian Cryogenian Middle 157.3 ±1.0 Upper proterozoic ~ 720 Pleistocene 0.781 372.2 ±1.6 Calabrian Oxfordian Tonian 1.80 163.5 ±1.0 Frasnian Callovian 1000 Quaternary Gelasian 166.1 ±1.2 2.58 Bathonian 382.7 ±1.6 Stenian Middle 168.3 ±1.3 Piacenzian Bajocian 170.3 ±1.4 Givetian 1200 Pliocene 3.600 Middle 387.7 ±0.8 Meso- Zanclean Aalenian proterozoic Ectasian 5.333 174.1 ±1.0 Eifelian 1400 Messinian Jurassic 393.3 ±1.2 7.246 Toarcian Devonian Calymmian Tortonian 182.7 ±0.7 Emsian 1600 11.63 Pliensbachian Statherian Lower 407.6 ±2.6 Serravallian 13.82 190.8 ±1.0 Lower 1800 Miocene Pragian 410.8 ±2.8 Proterozoic Neogene Sinemurian Langhian 15.97 Orosirian 199.3 ±0.3 Lochkovian Paleo- 2050 Burdigalian Hettangian 201.3 ±0.2 419.2 ±3.2 proterozoic 20.44 Mesozoic Rhaetian Pridoli Rhyacian Aquitanian 423.0 ±2.3 23.03 ~ 208.5 Ludfordian 2300 Cenozoic Chattian Ludlow 425.6 ±0.9 Siderian 27.82 Gorstian -
Chemostratigraphic Correlations Across the First Major Trilobite
www.nature.com/scientificreports OPEN Chemostratigraphic correlations across the frst major trilobite extinction and faunal turnovers between Laurentia and South China Jih-Pai Lin 1*, Frederick A. Sundberg2, Ganqing Jiang3, Isabel P. Montañez4 & Thomas Wotte5 During Cambrian Stage 4 (~514 Ma) the oceans were widely populated with endemic trilobites and three major faunas can be distinguished: olenellids, redlichiids, and paradoxidids. The lower–middle Cambrian boundary in Laurentia was based on the frst major trilobite extinction event that is known as the Olenellid Biomere boundary. However, international correlation across this boundary (the Cambrian Series 2–Series 3 boundary) has been a challenge since the formal proposal of a four-series subdivision of the Cambrian System in 2005. Recently, the base of the international Cambrian Series 3 and of Stage 5 has been named as the base of the Miaolingian Series and Wuliuan Stage. This study provides detailed chemostratigraphy coupled with biostratigraphy and sequence stratigraphy across this critical boundary interval based on eight sections in North America and South China. Our results show robust isotopic evidence associated with major faunal turnovers across the Cambrian Series 2–Series 3 boundary in both Laurentia and South China. While the olenellid extinction event in Laurentia and the gradual extinction of redlichiids in South China are linked by an abrupt negative carbonate carbon excursion, the frst appearance datum of Oryctocephalus indicus is currently the best horizon to achieve correlation between the two regions. Te international correlation of the traditional lower–middle Cambrian boundary has been exceedingly difcult primarily due to apparent diachroniety of the datum species used to defne the boundary refecting the endemic faunas. -
Kimmigj CV 20190807
Kimmig Julien Karl Franck Kimmig Curriculum vitae 2895 Pauling Ave Apt. 334 Richland, WA 99354 Phone: 785-766-2386 Email: [email protected] Education Ph.D. in “Geology” 2014 University of Saskatchewan (Canada) Thesis title: Taxonomy, taphonomy and paleocology of a new Burgess Shale-type Lagerstätte from the Mackenzie Mountains, Northwest Territories, Canada. M.Sc. in “Biology” 2009 Topic: Advanced Methods in Taxonomy and Biodiversity Imperial College London & Natural History Museum London (United Kingdom) B.Sc. in “Geosciences” 2008 Georg-August-Universität Göttingen (Germany) Professional experience Research Affiliate since August 2019 Division of Invertebrate Paleontology University of Kansas Collections Manager (Assistant Researcher) June 2016 – July 2019 Division of Invertebrate Paleontology University of Kansas Research Associate July 2015 – June 2019 University of Saskatchewan Postdoctoral Researcher October 2014 – June 2015 Supervisor: Brian Pratt University of Saskatchewan Teaching Assistant September 2011 – September 2014 University of Saskatchewan Adjunct Researcher September 2009 – May 2011 Supervisor: Alison Longbottom The Natural History Museum London Museum and Research Assistant December 2007 – September 2008 Supervisor: Mike Reich Geowissenschaftliches Museum Göttingen 1 Kimmig Selected fieldwork (Total ~ 160 days) Cambrian, Utah and Idaho, 2019 10 days Spence Shale, Wellsville Mountains, Utah, 2018 5 days Spence Shale, Wellsville Mountains, Utah, 2017 15 days Ravens Throat River, Mackenzie Mountains, Canada, 2012 28 days