1 John A. Tarduno
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Assembly, Configuration, and Break-Up History of Rodinia
Author's personal copy Available online at www.sciencedirect.com Precambrian Research 160 (2008) 179–210 Assembly, configuration, and break-up history of Rodinia: A synthesis Z.X. Li a,g,∗, S.V. Bogdanova b, A.S. Collins c, A. Davidson d, B. De Waele a, R.E. Ernst e,f, I.C.W. Fitzsimons g, R.A. Fuck h, D.P. Gladkochub i, J. Jacobs j, K.E. Karlstrom k, S. Lu l, L.M. Natapov m, V. Pease n, S.A. Pisarevsky a, K. Thrane o, V. Vernikovsky p a Tectonics Special Research Centre, School of Earth and Geographical Sciences, The University of Western Australia, Crawley, WA 6009, Australia b Department of Geology, Lund University, Solvegatan 12, 223 62 Lund, Sweden c Continental Evolution Research Group, School of Earth and Environmental Sciences, University of Adelaide, Adelaide, SA 5005, Australia d Geological Survey of Canada (retired), 601 Booth Street, Ottawa, Canada K1A 0E8 e Ernst Geosciences, 43 Margrave Avenue, Ottawa, Canada K1T 3Y2 f Department of Earth Sciences, Carleton U., Ottawa, Canada K1S 5B6 g Tectonics Special Research Centre, Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, WA 6845, Australia h Universidade de Bras´ılia, 70910-000 Bras´ılia, Brazil i Institute of the Earth’s Crust SB RAS, Lermontova Street, 128, 664033 Irkutsk, Russia j Department of Earth Science, University of Bergen, Allegaten 41, N-5007 Bergen, Norway k Department of Earth and Planetary Sciences, Northrop Hall University of New Mexico, Albuquerque, NM 87131, USA l Tianjin Institute of Geology and Mineral Resources, CGS, No. -
Curriculum Vitae
TIMOTHY JAMES BRALOWER Department of Geosciences Pennsylvania State University University Park, PA 16802 [email protected] www.globalnannoplankton.com Education: Ph.D. Earth Sciences, Scripps Institution of Oceanography, University of California, San Diego, 1986. M.S. Oceanography, Scripps Institution of Oceanography, University of California, San Diego, 1982. B.A. with Honours in Geology, Oxford University, England, 1980. Professional Experience: Professor, Department of Geosciences, Pennsylvania State University, 2003-. Head, Department of Geosciences, Pennsylvania State University, 2003-2011; 2017-2018. Chair, Department of Geological Sciences, University of North Carolina, Chapel Hill, 1998-2002. Joseph Sloane Professor of Geological and Marine Sciences, University of North Carolina, Chapel Hill, 1998-2002. Associate Professor of Geological and Marine Sciences, University of North Carolina, Chapel Hill, 1993-1998. Assistant Professor, Geological and Marine Sciences, University of North Carolina, Chapel Hill, 1990-1993. Assistant Professor, Florida International University, State University of Florida at Miami, 1987-1990. ODP/IODP: Shipboard biostratigrapher, Leg 122 (Indian Ocean, 1988), Leg 143 (Pacific Ocean, 1993), Leg 165 (Caribbean, 1995), Expedition 364 (Chicxulub, 2016). Co-chief scientist, ODP Leg 198 (Pacific, 2001). Honors: Hettelman Junior Faculty Research Prize, UNC-CH, 1995. Fulbright Senior Scholarship, University of New South Wales, 2011-12. Wilson Service Award, College of Earth and Mineral Sciences, PSU, 2015; G. Montgomery and Marion Mitchell Award for Innovative Teaching, College of Earth and Mineral Sciences, PSU, 2017; George W. Atherton Award for Excellence in Teaching, PSU Systemwide Highest Award 2020. Memberships: AGU, GSA, NAGT Publications: http://scholar.google.com/citations?user=q4WEgGYAAAAJ&hl=en&oi=ao Partial list of Professional Service (past 20 years) . -
Geophysical Field Mapping
Presented at Short Course IX on Exploration for Geothermal Resources, organized by UNU-GTP, GDC and KenGen, at Lake Bogoria and Lake Naivasha, Kenya, Nov. 2-23, 2014. Kenya Electricity Generating Co., Ltd. GEOPHYSICAL FIELD MAPPING Anastasia W. Wanjohi, Kenya Electricity Generating Company Ltd. Olkaria Geothermal Project P.O. Box 785-20117, Naivasha KENYA [email protected] or [email protected] ABSTRACT Geophysics is the study of the earth by the quantitative observation of its physical properties. In geothermal geophysics, we measure the various parameters connected to geological structure and properties of geothermal systems. Geophysical field mapping is the process of selecting an area of interest and identifying all the geophysical aspects of the area with the purpose of preparing a detailed geophysical report. The objective of geophysical field work is to understand all physical parameters of a geothermal field and be able to relate them with geological phenomenons and come up with plausible inferences about the system. Four phases are involved and include planning/desktop studies, reconnaissance, actual data aquisition and report writing. Equipments must be prepared and calibrated well. Geophysical results should be processed, analysed and presented in the appropriate form. A detailed geophysical report should be compiled. This paper presents the reader with an overview of how to carry out geophysical mapping in a geothermal field. 1. INTRODUCTION Geophysics is the study of the earth by the quantitative observation of its physical properties. In geothermal geophysics, we measure the various parameters connected to geological structure and properties of geothermal systems. In lay man’s language, geophysics is all about x-raying the earth and involves sending signals into the earth and monitoring the outcome or monitoring natural signals from the earth. -
Mantle Flow Through the Northern Cordilleran Slab Window Revealed by Volcanic Geochemistry
Downloaded from geology.gsapubs.org on February 23, 2011 Mantle fl ow through the Northern Cordilleran slab window revealed by volcanic geochemistry Derek J. Thorkelson*, Julianne K. Madsen, and Christa L. Sluggett Department of Earth Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada ABSTRACT 180°W 135°W 90°W 45°W 0° The Northern Cordilleran slab window formed beneath west- ern Canada concurrently with the opening of the Californian slab N 60°N window beneath the southwestern United States, beginning in Late North Oligocene–Miocene time. A database of 3530 analyses from Miocene– American Holocene volcanoes along a 3500-km-long transect, from the north- Juan Vancouver Northern de ern Cascade Arc to the Aleutian Arc, was used to investigate mantle Cordilleran Fuca conditions in the Northern Cordilleran slab window. Using geochemi- Caribbean 30°N Californian Mexico Eurasian cal ratios sensitive to tectonic affi nity, such as Nb/Zr, we show that City and typical volcanic arc compositions in the Cascade and Aleutian sys- Central African American Cocos tems (derived from subduction-hydrated mantle) are separated by an Pacific 0° extensive volcanic fi eld with intraplate compositions (derived from La Paz relatively anhydrous mantle). This chemically defi ned region of intra- South Nazca American plate volcanism is spatially coincident with a geophysical model of 30°S the Northern Cordilleran slab window. We suggest that opening of Santiago the slab window triggered upwelling of anhydrous mantle and dis- Patagonian placement of the hydrous mantle wedge, which had developed during extensive early Cenozoic arc and backarc volcanism in western Can- Scotia Antarctic Antarctic 60°S ada. -
Geological Evolution of the Red Sea: Historical Background, Review and Synthesis
See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/277310102 Geological Evolution of the Red Sea: Historical Background, Review and Synthesis Chapter · January 2015 DOI: 10.1007/978-3-662-45201-1_3 CITATIONS READS 6 911 1 author: William Bosworth Apache Egypt Companies 70 PUBLICATIONS 2,954 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Near and Middle East and Eastern Africa: Tectonics, geodynamics, satellite gravimetry, magnetic (airborne and satellite), paleomagnetic reconstructions, thermics, seismics, seismology, 3D gravity- magnetic field modeling, GPS, different transformations and filtering, advanced integrated examination. View project Neotectonics of the Red Sea rift system View project All content following this page was uploaded by William Bosworth on 28 May 2015. The user has requested enhancement of the downloaded file. All in-text references underlined in blue are added to the original document and are linked to publications on ResearchGate, letting you access and read them immediately. Geological Evolution of the Red Sea: Historical Background, Review, and Synthesis William Bosworth Abstract The Red Sea is part of an extensive rift system that includes from south to north the oceanic Sheba Ridge, the Gulf of Aden, the Afar region, the Red Sea, the Gulf of Aqaba, the Gulf of Suez, and the Cairo basalt province. Historical interest in this area has stemmed from many causes with diverse objectives, but it is best known as a potential model for how continental lithosphere first ruptures and then evolves to oceanic spreading, a key segment of the Wilson cycle and plate tectonics. -
Uncorking the Bottle: What Triggered the Paleocene/Eocene Thermal Maximum Methane Release? Miriame
PALEOCEANOGRAPHY, VOL. 16, NO. 6, PAGES 549-562, DECEMBER 2001 Uncorking the bottle: What triggered the Paleocene/Eocene thermal maximum methane release? MiriamE. Katz,• BenjaminS. Cramer,Gregory S. Mountain,2 Samuel Katz, 3 and KennethG. Miller,1,2 Abstract. The Paleocene/Eocenethermal maximum (PETM) was a time of rapid global warming in both marine and continentalrealms that has been attributed to a massivemethane (CH4) releasefrom marine gas hydrate reservoirs. Previously proposedmechanisms for thismethane release rely on a changein deepwatersource region(s) to increasewater temperatures rapidly enoughto trigger the massivethermal dissociationof gas hydratereservoirs beneath the seafloor.To establish constraintson thermaldissociation, we modelheat flow throughthe sedimentcolumn and showthe effectof the temperature changeon the gashydrate stability zone throughtime. In addition,we provideseismic evidence tied to boreholedata for methanerelease along portions of the U.S. continentalslope; the releasesites are proximalto a buriedMesozoic reef front. Our modelresults, release site locations, published isotopic records, and oceancirculation models neither confirm nor refute thermaldissociation as the triggerfor the PETM methanerelease. In the absenceof definitiveevidence to confirmthermal dissociation,we investigatean altemativehypothesis in which continentalslope failure resulted in a catastrophicmethane release.Seismic and isotopic evidence indicates that Antarctic source deepwater circulation and seafloor erosion caused slope retreatalong -
Sterngeryatctnphys18.Pdf
Tectonophysics 746 (2018) 173–198 Contents lists available at ScienceDirect Tectonophysics journal homepage: www.elsevier.com/locate/tecto Subduction initiation in nature and models: A review T ⁎ Robert J. Sterna, , Taras Geryab a Geosciences Dept., U Texas at Dallas, Richardson, TX 75080, USA b Institute of Geophysics, Dept. of Earth Sciences, ETH, Sonneggstrasse 5, 8092 Zurich, Switzerland ARTICLE INFO ABSTRACT Keywords: How new subduction zones form is an emerging field of scientific research with important implications for our Plate tectonics understanding of lithospheric strength, the driving force of plate tectonics, and Earth's tectonic history. We are Subduction making good progress towards understanding how new subduction zones form by combining field studies to Lithosphere identify candidates and reconstruct their timing and magmatic evolution and undertaking numerical modeling (informed by rheological constraints) to test hypotheses. Here, we review the state of the art by combining and comparing results coming from natural observations and numerical models of SI. Two modes of subduction initiation (SI) can be identified in both nature and models, spontaneous and induced. Induced SI occurs when pre-existing plate convergence causes a new subduction zone to form whereas spontaneous SI occurs without pre-existing plate motion when large lateral density contrasts occur across profound lithospheric weaknesses of various origin. We have good natural examples of 3 modes of subduction initiation, one type by induced nu- cleation of a subduction zone (polarity reversal) and two types of spontaneous nucleation of a subduction zone (transform collapse and plumehead margin collapse). In contrast, two proposed types of subduction initiation are not well supported by natural observations: (induced) transference and (spontaneous) passive margin collapse. -
Satellite Measured Ionospheric Magnetic Field Variations Over Natural Hazards Sites
remote sensing Article Satellite Measured Ionospheric Magnetic Field Variations over Natural Hazards Sites Christoph Schirninger 1,†, Hans U. Eichelberger 1,*,†, Werner Magnes 1 , Mohammed Y. Boudjada 1,†, Konrad Schwingenschuh 1,†, Andreas Pollinger 1, Bruno P. Besser 1, Pier F. Biagi 2 , Maria Solovieva 3, Jindong Wang 4, Bingjun Cheng 4, Bin Zhou 4, Xuhui Shen 5, Magda Delva 1 and Roland Lammegger 6 1 Space Research Institute, Austrian Academy of Sciences, Schmiedlstraße 6, 8042 Graz, Austria; [email protected] (C.S.); [email protected] (W.M.); [email protected] (M.Y.B.); [email protected] (K.S.); [email protected] (A.P.); [email protected] (B.P.B.); [email protected] (M.D.) 2 Department of Physics, University of Bari, 70126 Bari, Italy; [email protected] 3 Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, 123995 Moscow, Russia; [email protected] 4 National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China; [email protected] (J.W.); [email protected] (B.C.); [email protected] (B.Z.) 5 National Institute of Natural Hazards, MEMC, Beijing 100085, China; [email protected] 6 Institute of Experimental Physics, Graz University of Technology, 8010 Graz, Austria; [email protected] * Correspondence: [email protected] † These authors contributed equally to this work. Citation: Schirninger, C.; Eichelberger, H.U.; Magnes, W.; Abstract: Processes and threats related to natural hazards play an important role in the evolution of Boudjada, M.Y.; Schwingenschuh, K.; the Earth and in human history. -
Ocean Drilling Program Initial Reports Volume
Winterer, E.L., Sager, W.W., Firth, J.V., and Sinton, J.M. (Eds.), 1995 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 143 30. SEDIMENT FACIES AND ENVIRONMENTS OF DEPOSITION ON CRETACEOUS PACIFIC CARBONATE PLATFORMS: AN OVERVIEW OF DREDGED ROCKS FROM WESTERN PACIFIC GUYOTS1 Robert J. van Waasbergen2 ABSTRACT Many years of dredging of Cretaceous guyots in the western Pacific Ocean have shown the widespread occurrence of drowned carbonate platforms that were active in the Early to middle Cretaceous. Through petrographic analysis of available dredged limestone samples from these guyots, eight limestone lithofacies are distinguished, of which the first three are found in great abundance or in dredges from more than one guyot. The eight lithofacies are used to form a composite image of the depositional environments on the Cretaceous Pacific carbonate platforms. The most abundant facies (Facies 1) is a coarse bioclastic grainstone found in the forereef environment. Facies 2 comprises mudstone in which small bioclasts are rare to abundant. This facies is typical of the platform-interior ("lagoon") environment. Facies 3 comprises packstones and wackestones of peloids and coated grains, and is attributed to deposition in environments of moderate energy dominated by tidal currents. A number of lithofacies were recognized in only a few samples, or only in samples from a single guyot, and are therefor termed "minor" facie;. Facies 4 comprises muddy sponge-algal bafflestone deposits probably associated with shallow, platform-interior bioherms. Facies 5 comprises oolite grainstones and is attributed to high-energy platform-margin environments. Facies 6 is a mixed carbonate/siliciclastic deposit and may be associated with an episode of renewed volcanic activity on one of the guyots (Allison) in the Mid-Pacific Mountains. -
Modern and Ancient Hiatuses in the Pelagic Caps of Pacific Guyots and Seamounts and Internal Tides GEOSPHERE; V
Research Paper GEOSPHERE Modern and ancient hiatuses in the pelagic caps of Pacific guyots and seamounts and internal tides GEOSPHERE; v. 11, no. 5 Neil C. Mitchell1, Harper L. Simmons2, and Caroline H. Lear3 1School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester M13 9PL, UK doi:10.1130/GES00999.1 2School of Fisheries and Ocean Sciences, University of Alaska-Fairbanks, 905 N. Koyukuk Drive, 129 O’Neill Building, Fairbanks, Alaska 99775, USA 3School of Earth and Ocean Sciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK 10 figures CORRESPONDENCE: neil .mitchell@ manchester ABSTRACT landmasses were different. Furthermore, the maximum current is commonly .ac .uk more important locally than the mean current for resuspension and transport Incidences of nondeposition or erosion at the modern seabed and hiatuses of particles and thus for influencing the sedimentary record. The amplitudes CITATION: Mitchell, N.C., Simmons, H.L., and Lear, C.H., 2015, Modern and ancient hiatuses in the within the pelagic caps of guyots and seamounts are evaluated along with of current oscillations should therefore be of interest to paleoceanography, al- pelagic caps of Pacific guyots and seamounts and paleotemperature and physiographic information to speculate on the charac- though they are not well known for the geological past. internal tides: Geosphere, v. 11, no. 5, p. 1590–1606, ter of late Cenozoic internal tidal waves in the upper Pacific Ocean. Drill-core Hiatuses in pelagic sediments of the deep abyssal ocean floor have been doi:10.1130/GES00999.1. and seismic reflection data are used to classify sediment at the drill sites as interpreted from sediment cores (Barron and Keller, 1982; Keller and Barron, having been accumulating or eroding or not being deposited in the recent 1983; Moore et al., 1978). -
Initial Transgressive Phase of Leg 144 Guyots: Evidence of Extreme Sulfate Reduction
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Earth and Atmospheric Sciences, Department Papers in the Earth and Atmospheric Sciences of 1995 Initial Transgressive Phase of Leg 144 Guyots: Evidence of Extreme Sulfate Reduction Bjørn Buchardt University of Copenhagen Mary Anne Holmes University of Nebraska-Lincoln, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/geosciencefacpub Part of the Earth Sciences Commons Buchardt, Bjørn and Holmes, Mary Anne, "Initial Transgressive Phase of Leg 144 Guyots: Evidence of Extreme Sulfate Reduction" (1995). Papers in the Earth and Atmospheric Sciences. 62. https://digitalcommons.unl.edu/geosciencefacpub/62 This Article is brought to you for free and open access by the Earth and Atmospheric Sciences, Department of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Papers in the Earth and Atmospheric Sciences by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Haggerty, J.A., Premoli Silva, I., Rack, F., and McNutt, M.K. (Eds.), 1995 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 144 51. INITIAL TRANSGRESSIVE PHASE OF LEG 144 GUYOTS: EVIDENCE OF EXTREME SULFATE REDUCTION1 Bjorn Buchardt2 and Mary Anne Holmes3 ABSTRACT The initial transgressive phase at the Leg 144 Guyots is characterized by a typical association of sedimentary facies (from bottom to top): in situ weathered volcanic rocks; variegated clays, partly pyritic; gray clay, pyritic, homogeneous, or mottled; black clay, peaty, laminated, or bioturbated; and marine argillaceous limestone. Site 877 at Wodejebato Guyot represents the typical development of the initial transgressive phase. The black clay is rich in organic carbon (up to 40%) and sulfur (up to 25%). -
The Palaeocene – Eocene Thermal Maximum Super Greenhouse
The Palaeocene–Eocene Thermal Maximum super greenhouse: biotic and geochemical signatures, age models and mechanisms of global change A. SLUIJS1, G. J. BOWEN2, H. BRINKHUIS1, L. J. LOURENS3 & E. THOMAS4 1Palaeoecology, Institute of Environmental Biology, Utrecht University, Laboratory of Palaeobotany and Palynology, Budapestlaan 4, 3584 CD Utrecht, The Netherlands (e-mail: [email protected]) 2Earth and Atmospheric Sciences, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN 47907, USA 3Faculty of Geosciences, Department of Earth Sciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, The Netherlands 4Center for the Study of Global Change, Department of Geology and Geophysics, Yale University, New Haven CT 06520-8109, USA; also at Department of Earth & Environmental Sciences, Wesleyan University, Middletown, CT, USA Abstract: The Palaeocene–Eocene Thermal Maximum (PETM), a geologically brief episode of global warming associated with the Palaeocene–Eocene boundary, has been studied extensively since its discovery in 1991. The PETM is characterized by a globally quasi-uniform 5–8 8C warming and large changes in ocean chemistry and biotic response. The warming is associated with a negative carbon isotope excursion (CIE), reflecting geologically rapid input of large amounts of isotopically light CO2 and/or CH4 into the exogenic (ocean–atmosphere) carbon pool. The biotic response on land and in the oceans was heterogeneous in nature and severity, including radiations, extinctions and migrations. Recently, several events that appear