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Leg 192 Preliminary Report Basement Drilling of the Ontong Java Plateau Leg 192 Preliminary Report Basement Drilling of the Ontong Java Plateau Shipboard Scientific Party Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station TX 77845-9547 USA January 2001 PUBLISHER’S NOTES This report was prepared from shipboard files by scientists who participated in the cruise. The report was assembled under time constraints and does not contain all works and findings that will appear in the Initial Reports of the ODP Proceedings. Reference to the whole or to part of this report should be made as follows: Shipboard Scientific Party, 2001. Leg 192 Preliminary Report: Basement drilling of the Ontong Java Plateau. ODP Prelim. Rpt., 92 [Online]. Available from World Wide Web: <http://www-odp.tamu.edu/publications/prelim/192_prel/192PREL.PDF>. [Cited YYYY-MM-DD] Distribution: Electronic copies of this series may be obtained from the Ocean Drilling Program’s World Wide Web site at http://www-odp.tamu.edu/publications. This publication was prepared by the Ocean Drilling Program, Texas A&M University, as an account of work performed under the international Ocean Drilling Program, which is managed by Joint Oceanographic Institutions, Inc., under contract with the National Science Foundation. Funding for the program is provided by the following agencies: Australia/Canada/Chinese Taipei/Korea Consortium for Ocean Drilling Deutsche Forschungsgemeinschaft (Federal Republic of Germany) Institut National des Sciences de l’Univers-Centre National de la Recherche Scientifique (INSU- CNRS; France) Ocean Research Institute of the University of Tokyo (Japan) National Science Foundation (United States) Natural Environment Research Council (United Kingdom) European Science Foundation Consortium for Ocean Drilling (Belgium, Denmark, Finland, Iceland, Ireland, Italy, The Netherlands, Norway, Spain, Sweden, and Switzerland) Marine High-Technology Bureau of the State Science and Technology Commission of the People’s Republic of China DISCLAIMER Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the National Science Foundation, the participating agencies, Joint Oceanographic Institutions, Inc., Texas A&M University, or Texas A&M Research Foundation. Leg 192 Preliminary Report 3 The following scientists were aboard the JOIDES Resolution for Leg 192 of the Ocean Drilling Program: J. Godfrey Fitton Neil R. Banerjee Co-Chief Scientist Metamorphic Petrologist Department of Geology and Geophysics School of Earth and Ocean Sciences University of Edinburgh University of Victoria West Mains Road Petch 086, 3800 Finnerty Road Edinburgh, Scotland EH9 3JW Victoria BC V8W 5C2 United Kingdom Canada Phone: (44) 1 31 650 8529 Phone: (250) 472-4048 Fax: (44) 1 31 668 3184 Fax: (250) 721-6200 E-mail: [email protected] E-mail: [email protected] John J. Mahoney James A. Bergen Co-Chief Scientist Paleontologist (nannofossils) Department of Geology and Department of Geological Sciences Geophysics/SOEST CB 3315, Mitchell Hall Room 606A/D University of North Carolina University of Hawaii at Manoa Chapel Hill NC 27599 1680 East-West Road USA Honolulu HI 96822 Phone: (919) 962-4379 USA E-mail: [email protected] Phone: (808) 956-8705 Fax: (808) 956-5512 Graeme Cairns E-mail: [email protected] Logging Staff Scientist UBO, UMR 6538 Domaines Oceaniques Paul J. Wallace IUEM, Place Nicolas Copernic Staff Scientist 29280 Plouzane Ocean Drilling Program France Texas A&M University Phone: (33) 298-49-87-09 1000 Discovery Drive Fax: (33) 298-49-87-60 College Station TX 77845-3469 E-mail: [email protected] USA Phone: (979) 845-0879 Paterno R. Castillo Fax: (979) 845-0876 Igneous Petrologist E-mail: [email protected] Scripps Institution of Oceanography Geosciences Research Division Maria J. Antretter University of California, San Diego Physical Properties Specialist La Jolla CA 92093-0212 Institut für Allgemeine und USA Angewandte Geophysik und Phone: (858) 534-0383 Geophysikalisches Observato Fax: (858) 534-0784 Ludwig-Maximilians-Universität München E-mail: [email protected] Theresienstrasse 41/IV 80333 München Federal Republic of Germany Phone: (49) 89 2394 4231 Fax: (49) 89 2394 4205 E-mail: [email protected] 4 Leg 192 Preliminary Report Lynne M. Chambers Stuart A. Hall Igneous Petrologist Paleomagnetist Department of Geology and Geophysics Department of Geosciences University of Edinburgh Science and Research I (Room 312) Grant Institute, West Mains Road University of Houston Edinburgh, Scotland EH9 3JW 4800 Calhoun United Kingdom Houston TX 77204-5503 Phone: (44) 1 31 650 8524 USA Fax: (44) 1 31 668 3184 Phone: (713) 743-3416 E-mail: [email protected] Fax: (713) 748-7906 E-mail: [email protected] William J. Chazey III Inorganic Chemist José Honnorez Department of Civil Engineering and Metamorphic Petrologist Geological Sciences EOST-Géologie University of Notre Dame Université Louis Pasteur 156 Fitzpatrick Hall 1 rue Blessig Notre Dame IN 46556 F-67084 Strasbourg USA France Phone: (219) 631-4308 Phone: (33) 03-90-24-04-11 Fax: (219) 631-9236 Fax: (33) 03-88-36-72-35 E-mail: [email protected] E-mail: [email protected] Millard F. Coffin Stephanie P. Ingle Geophysicist/JOIDES Logging Scientist Igneous Petrologist Institute for Geophysics Départment des Sciences de la Terre et de University of Texas at Austin L’Environnement Building 600 Faculté des Sciences CP 160/02 4412 Spicewood Springs Road Université Libre de Bruxelles Austin TX 78759-8500 Avenue F.D. Roosevelt, 50 USA B-1050 Bruxelles Phone: (512) 471-0429 Belgium Fax: (512) 475-6338 Phone: (00) 32-2-650-22-40 E-mail: [email protected] Fax: (00) 32-2-650-37-48 E-mail: [email protected] Marguerite M. Godard Igneous Petrologist Loren W. Kroenke UMR5568 CNRS-UM2 Physical Properties Specialist Laboratoire de Tectonophysique cc49 Hawaii Institute of Geophysics and Université de Montpellier 2 Planetology/SOEST Case Courier 49 University of Hawaii at Manoa Place Eugène Bataillon 1680 East-West Road, POST 808 F-34095 Montpellier Honolulu HI 96822 France USA Phone: (33) 467-14-39-37 Phone: (808) 956-7845 Fax: (33) 467-14-36-03 Fax: (808) 956-3188 E-mail: [email protected] E-mail: [email protected] Leg 192 Preliminary Report 5 Kenneth G. MacLeod Peter Riisager Stratigrapher Paleomagnetist Department of Geological Sciences Danish Lithosphere Centre 101 Geological Sciences Building Øster Volgrade 10 University of Missouri DK-1350 Copenhagen Columbia MO 65211 Denmark USA Phone: (45) 38-14-2638 Phone: (573) 884-3118 Fax: (45) 33-11-0878 Fax: (573) 882-5458 E-mail: [email protected] E-mail: [email protected] Takahashi Sano Hajime Naruse Igneous Petrologist Sedimentologist College of Environment and Disaster Department of Geology and Mineralogy Research Faculty of Science Fuji Tokoha University Kyoto University Ohbuchi 325 Sakyo-ku Kitashirakawa Oiwakecho Fuji 417-0801 Kyoto 606-8502 Japan Japan Phone: (81) 545-37-2007 Phone: (81) 75-753-4150 Fax: (81) 545-36-2651 Fax: (81) 75-753-4189 E-mail: [email protected] E-mail: [email protected] Paul J. Sikora Clive R. Neal Paleontologist (foraminifers) Igneous Petrologist Energy and Geoscience Institute Department of Civil Engineering and University of Utah Geological Sciences 423 Wakara Way, Suite 300 156 Fitzpatrick Hall Salt Lake City UT 84108 University of Notre Dame USA Notre Dame IN 46556 Phone: (801) 581-4122 USA Fax: (801) 585-3540 Phone: (219) 631-8328 E-mail: [email protected] Fax: (219) 631-9236 E-mail: [email protected] Rosalind V. White Petrologist James G. Ogg Department of Geology Sedimentologist University of Leicester Department of Earth and Atmospheric Sciences University Road CIVL Building 1397 Leicester LE1 7RH Purdue University United Kingdom West Lafayette IN 47907-1397 Phone: (44) 116-252-3315 USA Fax: (44) 116-252-3918 Phone: (765) 494-0257 E-mail: [email protected] Fax: (765) 496-1210 E-mail: [email protected] 6 Leg 192 Preliminary Report Xixi Zhao Physical Properties Specialist Center for Study of Imaging and Dynamics of the Earth Department of Earth Sciences University of California, Santa Cruz 1156 High Street Santa Cruz CA 95064 USA Phone: (831) 459-4847 Fax: (831) 459-3074 E-mail: [email protected] Wietze van der Werff Sedimentologist Department of Earth Sciences University of Liverpool Jane Herdman Building Brownlow Street Liverpool L69 3BX United Kingdom Phone: (44) 151-749-5141 Fax: (44) 151-749-5141 E-mail: [email protected] Leg 192 Preliminary Report 7 SCIENTIFIC REPORT ABSTRACT With a surface area of 1.6 × 106 km2 and a volume of 4–5 × 107 km3, the Ontong Java Plateau is the world’s largest volcanic oceanic plateau and may represent the largest magmatic event on Earth in the last 200 m.y. During Ocean Drilling Program (ODP) Leg 192 we recovered igneous basement and sediment cores in five widely separated sites in previously unsampled areas across the plateau. Primary objectives of the leg were to determine (1) the age and duration of emplacement of the plateau, (2) the compositional range of magmatism, and (3) the environment and style of eruption. Acoustic basement at the four sites on the main or high plateau consists of pillow and/or massive basalt flows with rare, thin sedimentary interbeds. Biostratigraphic evidence indicates that basement ages at Sites 1183, 1186, and 1187 are Aptian. At Site 1185, two groups of basalt are present; the lower group is Aptian, whereas the age of the upper group is estimated only loosely as latest Cenomanian to Albian. These results, together with data from Deep Sea Drilling Project (DSDP) Site 289 and ODP Site 807, demonstrate that the great bulk of the high plateau formed in a single episode in the early Aptian. Later volcanic events, including the ~90-Ma event recorded at Site 803 and in the eastern Solomon Islands, appear to have been volumetrically minor on the high plateau and mainly confined to its margins.
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