1 CURRICULUM VITA William W. Sager
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Hikurangi Plateau: Crustal Structure, Rifted Formation, and Gondwana Subduction History
Article Geochemistry 3 Volume 9, Number 7 Geophysics 3 July 2008 Q07004, doi:10.1029/2007GC001855 GeosystemsG G ISSN: 1525-2027 AN ELECTRONIC JOURNAL OF THE EARTH SCIENCES Published by AGU and the Geochemical Society Click Here for Full Article Hikurangi Plateau: Crustal structure, rifted formation, and Gondwana subduction history Bryan Davy Institute of Geological and Nuclear Sciences, P.O. Box 30368, Lower Hutt, New Zealand ([email protected]) Kaj Hoernle IFM-GEOMAR, Wischhofstraße 1-3, D-24148 Kiel, Germany Reinhard Werner Tethys Geoconsulting GmbH, Wischhofstraße 1-3, D-24148 Kiel, Germany [1] Seismic reflection profiles across the Hikurangi Plateau Large Igneous Province and adjacent margins reveal the faulted volcanic basement and overlying Mesozoic-Cenozoic sedimentary units as well as the structure of the paleoconvergent Gondwana margin at the southern plateau limit. The Hikurangi Plateau crust can be traced 50–100 km southward beneath the Chatham Rise where subduction cessation timing and geometry are interpreted to be variable along the margin. A model fit of the Hikurangi Plateau back against the Manihiki Plateau aligns the Manihiki Scarp with the eastern margin of the Rekohu Embayment. Extensional and rotated block faults which formed during the breakup of the combined Manihiki- Hikurangi plateau are interpreted in seismic sections of the Hikurangi Plateau basement. Guyots and ridge- like seamounts which are widely scattered across the Hikurangi Plateau are interpreted to have formed at 99–89 Ma immediately following Hikurangi Plateau jamming of the Gondwana convergent margin at 100 Ma. Volcanism from this period cannot be separately resolved in the seismic reflection data from basement volcanism; hence seamount formation during Manihiki-Hikurangi Plateau emplacement and breakup (125–120 Ma) cannot be ruled out. -
Subsidence and Growth of Pacific Cretaceous Plateaus
ELSEVIER Earth and Planetary Science Letters 161 (1998) 85±100 Subsidence and growth of Paci®c Cretaceous plateaus Garrett Ito a,Ł, Peter D. Clift b a School of Ocean and Earth Science and Technology, POST 713, University of Hawaii at Manoa, Honolulu, HI 96822, USA b Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA Received 10 November 1997; revised version received 11 May 1998; accepted 4 June 1998 Abstract The Ontong Java, Manihiki, and Shatsky oceanic plateaus are among the Earth's largest igneous provinces and are commonly believed to have erupted rapidly during the surfacing of giant heads of initiating mantle plumes. We investigate this hypothesis by using sediment descriptions of Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) drill cores to constrain plateau subsidence histories which re¯ect mantle thermal and crustal accretionary processes. We ®nd that total plateau subsidence is comparable to that expected of normal sea¯oor but less than predictions of thermal models of hotspot-affected lithosphere. If crustal emplacement was rapid, then uncertainties in paleo-water depths allow for the anomalous subsidence predicted for plumes with only moderate temperature anomalies and volumes, comparable to the sources of modern-day hotspots such as Hawaii and Iceland. Rapid emplacement over a plume head of high temperature and volume, however, is dif®cult to reconcile with the subsidence reconstructions. An alternative possibility that reconciles low subsidence over a high-temperature, high-volume plume source is a scenario in which plateau subsidence is the superposition of (1) subsidence due to the cooling of the plume source, and (2) uplift due to prolonged crustal growth in the form of magmatic underplating. -
Cenozoic Changes in Pacific Absolute Plate Motion A
CENOZOIC CHANGES IN PACIFIC ABSOLUTE PLATE MOTION A THESIS SUBMITTED TO THE GRADUATE DIVISION OF THE UNIVERSITY OF HAWAI`I IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN GEOLOGY AND GEOPHYSICS DECEMBER 2003 By Nile Akel Kevis Sterling Thesis Committee: Paul Wessel, Chairperson Loren Kroenke Fred Duennebier We certify that we have read this thesis and that, in our opinion, it is satisfactory in scope and quality as a thesis for the degree of Master of Science in Geology and Geophysics. THESIS COMMITTEE Chairperson ii Abstract Using the polygonal finite rotation method (PFRM) in conjunction with the hotspot- ting technique, a model of Pacific absolute plate motion (APM) from 65 Ma to the present has been created. This model is based primarily on the Hawaiian-Emperor and Louisville hotspot trails but also incorporates the Cobb, Bowie, Kodiak, Foundation, Caroline, Mar- quesas and Pitcairn hotspot trails. Using this model, distinct changes in Pacific APM have been identified at 48, 27, 23, 18, 12 and 6 Ma. These changes are reflected as kinks in the linear trends of Pacific hotspot trails. The sense of motion and timing of a number of circum-Pacific tectonic events appear to be correlated with these changes in Pacific APM. With the model and discussion presented here it is suggested that Pacific hotpots are fixed with respect to one another and with respect to the mantle. If they are moving as some paleomagnetic results suggest, they must be moving coherently in response to large-scale mantle flow. iii List of Tables 4.1 Initial hotspot locations . -
$18 | 2021 the Explorers Club 50 the Explorers Club 50
$18 | 2021 THE EXPLORERS CLUB 50 THE EXPLORERS CLUB 50 acknowledgements contents 2021 FOUNDING CORPORATE SPONSOR OF THE COMMITTEE FOR DIVERSITY AND INCLUSION INITIATIVE THE EXPLORERS 50 PROJECT Discovery Communications Joseph Rohde, Chairman the explorers club 50 Jeff Blumenfeld Marc Bryan-Brown INTRODUCTION FIFTY EXPLORERS EXPLORERS CHANGING THE EXPLORERS CLUB MAKING THE BOOK SUPPORT OF THE Kim Frank Richard Wiese FN’89 TO KNOW THE WORLD FIFTY PROCESS Lee Langan MED’99 J.R. Harris 5 Joseph M. Rohde FN’10 J. Robert “J.R.” Harris ME’93 Kim N. Frank FN’18 120 EXPLORERS 50 Alexandra Sutton Lawrence 7 10 16 PROJECT Nancy Nenow Nancy Rosenthal Richard & Laetitia Garriott de Cayeux Jalsa Urubshurow Daniel & Lois Kobal Trevor Wallace Richard Wiese awardees Gladys Kalema Zikusoka RUBEN ALEMAN-LUCERO, 39 LATONIA HARTERY, 63 JAMES PRIGOFF, 32 MARGARET O’LEARY AMSLER, 88 JOHN HOUSTON, 47 SIAN PROCTOR, 92 MEMBERS NOMINATING AWARDEES JOEY ANGNATOK, 28 ANDERS JEPSEN, 104 LOSANG RABGEY, 72 CALLIE BROADDUS, 91 SHELTON JOHNSON, 64 SAMUEL E. SULEIMAN RAMOS, 95 BRANDI DECARLI, 52 AYANA ELIZABETH JOHNSON, 67 MAMY RAZAFITSALAMA, 99 Bob Atwater Timothy Jacob Ann Passer SUPRAJA DHARINI, 24 INIT KEITH, 107 MARIO RIGBY, 48 Kathryn Britnell Lisa Keating Milbry Polk JUSTIN DUNNAVANT, 56 PETER LALAMPAA , 36 AVIJAHN SAHA, 60 Gov. Doug Burgum Lee Langan Maureen Raymo SUSAN R. EATON, 96 CASUARINA MCKINNEY-LAMBERT, 112 FAWN SHARP, 100 Greg Carr Alexandra Sutton Lawrence Buffy Redsecker KAARE SIKUAQ ERICKSON, 35 DANIELLE LEE, 23 MICHEL STROGOFF, 31 Julie Chase Damien Leloup Joe Rohde VICKI LYNN FERRINI, 103 JENERIA LEKILELEI, 111 CHIP THOMAS, 119 AYANA FLEWELLEN, 20 BINBIN LI, 108 SCOTT THOMPSON, 53 Jack Daulton Rebecca Martin Faanya Rose BILLY GAUTHIER, 51 ONKURI MAJUMDAR, 44 SATEESH VANKATESH, 40 Matthew DeSantis Rob McCallum Travis Steffens DOMINQUE GONCALVES, 76 JUAN MARTINEZ-PINEDA, 115 DONALD WARNE, 71 Jason Edmunds Kevin McCarey Arnella Trent MARC O GRIOFA, 87 CRAIG MATHIESON, 83 PAIGE WEST, 79 Scott C. -
Marinegeology
_ I\_AGcO--',/_::,5 207247 Reprinted from /,v --,-/S--c/?-. MARINEGEOLOGY INTERNATIONAL JOURNAL OF MARINE GEOLOGY, GEOCHEMISTRY AND GEOPHYSICS Marine Geology 138 (1997) 273 301 Characteristics of seamounts near Hawaii as viewed by GLORIA Nathan T. Bridges Department of Geoscienees, University of Massachusetts, Amherst, MA 01003, USA Received 8 March 1996; accepted 19 November 1996 ELSEVIER ..... rZ MARINE QEOLOQY Editors-in-Chief For Europe, Africa and the Near East: H. Chamley, Universit(_ des Sciences et Techniques de Lille-Artois, S(_dimentologie et G_ochimie, B.P. 36, 59655 Villeneuve d'Ascq, France Tel.: +33-03 20 43 41 30 For the Americas, Pacific and Far East: M.A. Arthur, Department of Geosciences, The Pennsylvania State University, 503 Deike Building, University Park, PA 16802-2714, U.S.A. Tel.: + 1-814-865-6711; Fax: + 1-814-865-3191; E-mail: [email protected] Editorial Board R. Batiza, Honolulu, Hawaii, USA D. Jongsma, O'Connor, A.C.T., D.A. Ross, Woods Hole, Mass., USA W. Berger, La Jolla, Calif., USA Australia W.F. Ruddiman, Charlottesville, Va., USA A.H. Bouma, Baton Rouge, La., USA A.E.S. Kemp, Southampton, UK A.D. Short, Sydney, NSW, Australia A.J. Bowen, Halifax, N.S., Canada N.H. Kenyon, Southampton, UK D.J. Stanley, Washington, D.C., USA L. Carter, Wellington, New Zealand E.M. Klein, Durham, N.C., USA P. Stoffers, Kiel, Germany J.R. Curray, La Jolla, Calif., USA H.J. Knebel, Woods Hole, Mass., USA A.H.B. Stride, Petersfield, UK P.J. Davies, Sydney, N.S.W., Australia S.A. -
SO225 MANIHIKI II Weekly Report No
SO225 MANIHIKI II Weekly Report No. 1 R/V SONNE (19.11. – 25.11.2012) 10°13,6´S / 165°52,0´W The starting point of R/V SONNE expedition SO-225 was the port of Suva on Viti Levu island (Fiji). After 48 hours of travel the first group of scientists, engineers, and technicians from Germany arrived safe but somewhat tiered in Suva in the late evening of Saturday the 19th of November. There, the unloading of nine containers with scientific equipment for SO-225 and the mobilization of the remotely operated vehicle ROV Kiel 6000 kept us busy during the following days. In the evening of November 19th, the remaining scientists arrived in Suva, finally completing the scientific party of the SO-225 expedition. In tropical heat and occasionally heavy rain showers we managed to finish all port related cruise preparations on time thanks to the excellent support from the SONNE crew. Approximately one hour after a test program of the ROV Kiel 6000 was successfully completed, RV SONNE left Suva and headed towards the Manihiki Plateau, located ~1.000 nm to the northeast of Fiji in the area of the northern Cook Islands. Views of Suva/Fiji upon departure of R/V Sonne. RV Sonne cruises SO-224 and SO-225 are part of the cooperative project MANIHIKI II between GEOMAR and the Alfred Wegener Institute for Polar and Marine Research (AWI), funded by the German Ministry of Education and Research (BMBF). This multidisciplinary project continues previous research at the Manihiki Plateau conducted since 2007 (SO-193) on morphological, volcanological, geochemical, and geochronological studies and is now broadened by geophysical and paleoceanographic research foci. -
32. Radiometric Ages of Basement Lavas Recovered at Loen, Wodejebato, Mit, and Takuyo-Daisan Guyots, Northwestern Pacific Ocean1
Haggerty, J.A., Premoli Silva, I., Rack, F., and McNutt, M.K. (Eds.), 1995 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 144 32. RADIOMETRIC AGES OF BASEMENT LAVAS RECOVERED AT LOEN, WODEJEBATO, MIT, AND TAKUYO-DAISAN GUYOTS, NORTHWESTERN PACIFIC OCEAN1 Malcolm S. Pringle2 and Robert A. Duncan3 ABSTRACT The best estimate for the age of the oldest volcanism recovered from the summits of Loen, Wodejebato, MIT, and Takuyo- Daisan guyots, northwestern Pacific Ocean, is 113, 83, 123, and 118 Ma, respectively. All of these sites originated in the central and western regions of the South Pacific Isotopic and Thermal Anomaly (SOPITA). The 113-Ma age for Loen Guyot is signifi- cantly different from the 76-Ma age of volcanism under the carbonate platform of its neighbor, the living Anewetak Atoll, and suggests that drowned guyot/living atoll seamount pairs may have no genetically significant relationship other than geographic proximity. Although all of the basalts recovered from the top of Wodejebato Guyot were erupted during polarity Chron 33R (ca. 79-85 Ma), both the occurrence of reworked Cenomanian calcareous nannofossils in one of the summit cores and the existence of a thick Cenomanian volcaniclastic sequence, including 94-Ma basaltic clasts, in the archipelagic apron indicate that there must have been a Cenomanian or older edifice beneath the drilled summit volcanics. AT MIT Guyot, two late-stage periods of volcanism can be recognized: late Aptian (ca. 115 Ma) phreatomagmatic eruptions through the existing volcanic and carbonate platform, and 120-Ma hawaiites seen both as exotic clasts in the 115-Ma tuffs and as lava flows at the top of the basement sequence. -
Cook Islands Seabed Minerals : a Precautionary Approach to Mining / Gerald Mccormack
Cook Islands Seabed Minerals a precautionary approach to mining Gerald McCormack second edition, with corrections Cook Islands Natural Heritage Trust Rarotonga 2016 1° = primary 2° = secondary dt = dry tonnes M = million Ma = million years (from megaannus) for dates and duration mbsl = metres below sea level Mdt/y = million dry tonnes per year M/y = million per year ppm = parts per million t = tonne = 1,000kg (a.k.a. metric ton with symbol mt) wt = wet tonnes AABW = Antarctic Bottom Water BPA = Biodiversity Preservation Area CBD = Convention on Biological Diversity CISWF = Cook Islands Sovereign Wealth Fund CCD = Carbonate Compensation Depth CCZ = Clarion-Clipperton Zone DSC = Deep Sound Channel EEZ = Exclusive Economic Zone EIA - Environmental Impact Assessment GDP = Gross Domestic Product REY = Rare Earth Elements + Yttrium SBMA = Cook Islands Seabed Minerals Authority SMS = Seabed Massive Sulphides SPB = South Penrhyn Basin ISA = International Seabed Authority, a UN agency WCPFC = Western and Central Pacific Fisheries Commission Front cover An oblique view of the Cook Islands seafloor with the South Penrhyn Basin and its nodule fields in the foreground and the Manihiki Plateau in the background. Cook Islands Seabed Minerals a precautionary approach to mining Gerald McCormack second edition, with corrections Cook Islands Natural Heritage Trust Rarotonga 2016 Text and illustrations are licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. This means they are free for non-commercial use provided the author and illustrator are acknowledged. For other uses please contact the Cook Islands Natural Heritage Trust. The author extends his appreciation to the Minister of Natural Heritage, the Hon. Kiriau Turepu and to the Trust Chair, Ian Karika and his Board for their encouragement and support. -
Geochemistry and Age of Shatsky, Hess, and Ojin Rise Seamounts: Implications for a Connection Between the Shatsky and Hess Rises
Accepted Manuscript Geochemistry and Age of Shatsky, Hess, and Ojin Rise seamounts: Implications for a connection between the Shatsky and Hess Rises Maria Luisa G. Tejada, Jörg Geldmacher, Folkmar Hauff, Daniel Heaton, Anthony A.P. Koppers, Dieter Garbe-Schönberg, Kaj Hoernle, Ken Heydolph, William W. Sager PII: S0016-7037(16)30165-X DOI: http://dx.doi.org/10.1016/j.gca.2016.04.006 Reference: GCA 9701 To appear in: Geochimica et Cosmochimica Acta Received Date: 4 September 2015 Accepted Date: 1 April 2016 Please cite this article as: Tejada, M.L.G., Geldmacher, J., Hauff, F., Heaton, D., Koppers, A.A.P., Garbe- Schönberg, D., Hoernle, K., Heydolph, K., Sager, W.W., Geochemistry and Age of Shatsky, Hess, and Ojin Rise seamounts: Implications for a connection between the Shatsky and Hess Rises, Geochimica et Cosmochimica Acta (2016), doi: http://dx.doi.org/10.1016/j.gca.2016.04.006 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. 1 Geochemistry and Age of Shatsky, Hess, and Ojin Rise seamounts: Implications 2 for a connection between the Shatsky and Hess Rises 3 Maria Luisa G. Tejada a,b*, Jörg Geldmacher c, Folkmar Hauff c, Daniel Heaton d, Anthony A. -
Geomorphometric Descriptions of Archipelagic Aprons Off the Southern Flanks of French Frigate Shoals and Necker Island Edifices, Northwest Hawaiian Ridge
Geomorphometric descriptions of archipelagic aprons off the southern flanks of French Frigate Shoals and Necker Island edifices, Northwest Hawaiian Ridge James V. Gardner†, Brian R. Calder†, and Andrew A. Armstrong† Center for Coastal and Ocean Mapping–Joint Hydrographic Center, 24 Colovos Road, University of New Hampshire, Durham, New Hampshire 03824, USA ABSTRACT landslides are more recent, perhaps even Vogt and Smoot, 1984; Smoot, 1985), or mesh Quaternary in age. The presence of a chute- grids (e.g., Taylor et al., 1975, 1980; Smoot, This study describes the geomorphometries like feature on the mid-flank of the French 1982, 1983a, 1983b, 1985). Recently, studies of archipelagic aprons on the southern flanks Frigate Shoals edifice appears to be the result have utilized modern multibeam data (e.g., De- of the French Frigate Shoals and Necker Is- of rejuvenated volcanism that occurred long plus et al., 2001; Masson et al., 2002; Mitchell land edifices on the central Northwest Hawai- after the initial volcanism ceased to build the et al., 2002; Bohannon and Gardner, 2004; Silver ian Ridge that are hotspot volcanoes that have edifice. et al., 2009; Casalbore et al., 2010; Montanaro been dormant for 10–11 m.y. The archipe- and Beget, 2011; Watt et al., 2012b, 2014; Saint- lagic aprons are related to erosional headwall INTRODUCTION Ange et al., 2013; Ramalho et al., 2015; Watson scarps and gullies on landslide surfaces but et al., 2017; Clare et al., 2018; Counts et al., also include downslope gravitational features Archipelagic aprons are submarine landslide 2018; Pope et al., 2018; Quartau et al., 2018; that include slides, debris avalanches, bed- complexes composed of erosion and deposition- Santos et al., 2019; Casalbore et al., 2020) to form fields, and outrunners. -
Pacific-Panthalassic Reconstructions
RESEARCH ARTICLE Pacific‐Panthalassic Reconstructions: Overview, Errata 10.1029/2019GC008402 and the Way Forward Key Points: Trond H. Torsvik1,2 , Bernhard Steinberger3,1 , Grace E. Shephard1 , • We devised a new absolute Late 1 1 1 1 Jurassic‐Cretaceous Pacific plate Pavel V. Doubrovine , Carmen Gaina , Mathew Domeier , Clinton P. Conrad , model and William W. Sager4 • This study was motivated because published Pacific plate models 1Centre for Earth Evolution and Dynamics (CEED), University of Oslo, Oslo, Norway, 2School of Geosciences, University – fl (83.5 150 Ma) are variably awed of Witwatersrand, Johannesburg, South Africa, 3Helmholtz Centre Potsdam, GFZ, Potsdam, Germany, 4Department of • The emplacement of the Shatsky Rise Large Igneous Province at ~144 Earth and Atmospheric Sciences, University of Houston, Houston, TX, USA Ma caused a major plate boundary reorganization Abstract We have devised a new absolute Late Jurassic‐Cretaceous Pacific plate model using a fixed hot spot approach coupled with paleomagnetic data from Pacific large igneous provinces (LIPs) while simultaneously minimizing plate velocity and net lithosphere rotation (NR). This study was motivated Correspondence to: fi ‐ ‐ fl T. H. Torsvik, because published Paci c plate models for the 83.5 to 150 Ma time interval are variably awed, and their [email protected] use affects modeling of the entire Pacific‐Panthalassic Ocean and interpretation of its margin evolution. These flaws could be corrected, but the revised models would imply unrealistically high plate velocities fi Citation: and NR. We have developed three new Paci c realm models with varying degrees of complexity, but we Torsvik, T. H., Steinberger, B., focus on the one that we consider most realistic. -
Lumina 4C M02 TRUJ3545 1
Tall mountains created by tectonic uplift. Tall coastal mountains such as these in Glacier Bay National Park in southeastern Alaska have been uplifted by plate tectonic processes, creating a large amount of relief. Some of the uplifted rocks here have come from distant areas and include parts of the sea floor. M02_TRUJ3545_12_SE_C02.indd 38 16/12/15 3:49 AM 2 Before you begin reading this chapter, use the glossary at the end of this book to discover the meanings of any of the words in the word cloud Plate Tectonics above you don’t already know. and the Ocean Floor ach year at various locations around the globe, several thousand earthquakes Eand dozens of volcanic eruptions occur, both of which indicate how remarkably ESSENTIAL LEARNING CONCEPTS dynamic our planet is. These events have occurred throughout history, constantly At the end of this chapter, you should be able to: changing the surface of our planet, yet only a little over 50 years ago, most scientists believed the continents were stationary over geologic time. Since that time, a bold 2.1 Evaluate the evidence that supports new theory has been advanced that helps explain surface features and phenomena continental drift. on Earth, including: 2.2 Summarize the evidence that supports plate tectonics. • The worldwide locations of volcanoes, faults, earthquakes, and mountain building • Why mountains on Earth haven’t been eroded away 2.3 Discuss the origin and characteristics of features that occur at plate boundaries. • The origin of most landforms and ocean floor features 2.4 Show how plate tectonics can be used as a • How the continents and ocean floor formed and why they are different working model.