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Integrated Ocean Drilling Program Expedition 305 Preliminary Report Oceanic Core Complex Formation, Atlantis Massif Oceanic core complex formation, Atlantis Massif, Mid-Atlantic Ridge: drilling into the footwall and hanging wall of a tectonic exposure of deep, young oceanic lithosphere to study deformation, alteration, and melt generation 8 January–2 March 2005 Expedition Scientific Party PUBLISHER’S NOTES Material in this publication may be copied without restraint for library, abstract service, educational, or personal research purposes; however, this source should be appropriately acknowledged. Citation: Expedition Scientific Party, 2005. Oceanic core complex formation, Atlantis Massif—oceanic core complex formation, Atlantis Massif, Mid-Atlantic Ridge: drilling into the footwall and hanging wall of a tectonic exposure of deep, young oceanic lithosphere to study deformation, alteration, and melt generation. IODP Prel. Rept., 305. http://iodp.tamu.edu/publications/PR/305PR/305PR.PDF. Distribution: Electronic copies of this series may be obtained from the Integrated Ocean Drilling Program (IODP) Publication Services homepage on the World Wide Web at iodp.tamu.edu/publications. This publication was prepared by the Integrated Ocean Drilling Program U.S. Implementing Organization (IODP-USIO): Joint Oceanographic Institutions, Inc., Lamont-Doherty Earth Observatory of Columbia University, and Texas A&M University, as an account of work performed under the international Integrated Ocean Drilling Program, which is managed by IODP Management International (IODP-MI), Inc. Funding for the program is provided by the following agencies: European Consortium for Ocean Research Drilling (ECORD) Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan Ministry of Science and Technology (MOST), People’s Republic of China U.S. National Science Foundation (NSF) 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 participating agencies, IODP Management International, Inc., Joint Oceanographic Institutions, Inc., Lamont-Doherty Earth Observatory of Columbia University, Texas A&M University, or Texas A&M Research Foundation. April 2005 Expedition 305 Preliminary Report The following scientists and personnel were aboard the JOIDES Resolution for Expeditions 304 and 305 of the Integrated Ocean Drilling Program. Expedition Scientific Party Donna Blackman Yasuhiko Ohara Co-Chief Scientist Co-Chief Scientist Scripps Institution of Oceanography Ocean Research Laboratory University of California, San Diego Hydrographic and Oceanographic Department 9500 Gilman Drive of Japan La Jolla CA 92093-0225 5-3-1 Tsukiji, Chuo-ku USA Tokyo 104-0045 [email protected] Japan Work: (858) 534-8813 [email protected] Fax: (858) 534-5332 Work: (81) 3-3541-4387 Fax: (81) 3-3541-3870 Benoit Ildefonse Co-Chief Scientist D. Jay Miller Laboratoire de Tectonophysique Expedition Project Manager/Staff Scientist Université Montpellier II Integrated Ocean Drilling Program CC49 Texas A&M University 34095 Montpellier 1000 Discovery Drive France College Station TX 77845-9547 [email protected] USA Work: (33) 46714-3818 [email protected] Fax: (33) 46714-3603 Work: (979) 845-2197 Fax: (979) 845-0876 Barbara E. John Co-Chief Scientist Christopher J. MacLeod Department of Geology and Geophysics Shore-based Contributor University of Wyoming School of Earth, Ocean and Planetary Sciences 1000 East University Avenue Cardiff University Department 3006 Main Building, Park Place Laramie WY 82071 Cardiff CF10 3YE USA United Kingdom [email protected] [email protected] Work: (307) 766-4232 Work: (44) 29-208-74332 Fax: (307) 766-6679 Fax: (44) 29-208-74326 Expedition 305 Scientific Party Heike Delius Natsue Abe Logging Staff Scientist Igneous Petrologist Department of Geology Deep Sea Research Department University of Leicester Japan Marine Science and Technology Center University Road 2-15 Natsushima-cho Leicester LE1 7RH Yokosuka, Kanagawa 237-0061 United Kingdom Japan [email protected] [email protected] Phone: (44) 116-252-3634 Work: (81) 46-867-9329 Fax: (44) 116-252-3918 Fax: (81) 46-867-9315 3 Expedition 305 Preliminary Report James S. Beard Angela Halfpenny Metamorphic Petrologist Structural Geologist Department of Earth Sciences Department of Earth and Ocean Studies Virginia Museum of Natural History University of Liverpool 1001 Douglas Avenue 4 Brownlow Street Martinsville VA 24112 Liverpool, Merseyside L69 3GP USA United Kingdom [email protected] [email protected] Work: (276) 666-8611 Work: (44) 151-794-5174 Fax: (276) 632-6487 Fax: (44) 151-794-5196 Daniele Brunelli Heidi-Elisabeth Hansen Igneous Petrologist Igneous Petrologist Laboratoire Pierre Süe–DRECAM Department of Earth Science CNRS University of Bergen, Norway 91191 Yvette Cedex Allegaten 41 France Bergen [email protected] Norway Work: (33) 1-6908-9522 [email protected] Fax: (33) 1-6908-6923 Work: (47) 5531 3949 Adélie G. Delacour Amber C. Harris Metamorphic Petrologist Physical Properties Specialist Institut für Mineralogie und Petrographie Graduate School of Oceanography Eidgenössische Technische Hochschule–Zentrum University of Rhode Island Sonnegstrasse 5 Narragansett RI 02882 Zürich 8092 USA Switzerland [email protected] [email protected] Work: (401) 241-6874 Work: (41) 1 632 7823 Akihiro Tamura Hasebe Fax: (41) 1 632 1088 Igneous Petrologist Javier Escartin Department of Earth Sciences Structural Geologist Kanazawa University Marine Geosciences Kakuma, Kanazawa 920-1192 Université Pierre et Marie Curie Japan Case 89 IPGP [email protected] 4 Place Jussieu Work: (81) 76 264 5723 75252 Paris Fax: (81) 76 264 5746 France Eric Hellebrand [email protected] Igneous Petrologist Work: (33) 1-4427-4601 Abteilung Geochemie Fax: (33) 1-4427-9969 Max-Planck-Institüt für Chemie Patricia B. Fryer Postfach 3060 Metamorphic Petrologist 55020 Mainz School of Ocean and Earth Science and Technology Germany University of Hawaii at Manoa [email protected] 1680 East-West Road Work: (49) 6131-305220 Honolulu HI 96822 Fax: (49) 6131-371051 USA [email protected] Work: (808) 956-3146 Fax: (808) 956-6322 4 Expedition 305 Preliminary Report Satoko Ishimaru Katsuyoshi Michibayashi Igneous Petrologist Structural Geologist Division of Environmental Science and Engineering Institute of Geosciences Kanazawa University Shizuoka University Graduate School of Natural Science and Faculty of Science Technology 836 Oya Kakuma, Kanazawa 920-1192 Shizuoka 422-8529 Japan Japan [email protected] [email protected] Work: (81) 76-264-5723 Work: (81) 54-238-4788 Fax: (81) 76-264-5746 Fax: (81) 54-238-0491 Kevin T.M. Johnson Toshio Nozaka Igneous Petrologist Metamorphic Petrologist Department of Geology and Geophysics/SOEST Department of Earth Sciences University of Hawaii and Manoa Okayama University 1680 East-West Road 3-1-1 Tsushima-naka Post 606B Okayama 700-8530 Honolulu HI 96822 Japan USA [email protected] [email protected] Work: (81) 86-251-7883 Work: (808) 956-3444 Fax: (81) 86-251-7895 Fax: (808) 956-5512 Martin Rosner Garry D. Karner Geochemist Physical Properties Specialist Department of Marine Chemistry and Lamont-Doherty Earth Observatory Geochemistry of Columbia University Woods Hole Oceanographic Institution PO Box 1000, 61 Route 9W Clark Building, MS 23 Palisades NY 10964 Woods Hole MA 02543 USA USA [email protected] [email protected] Work: (845) 365-8355 Work: (508) 289-2699 Fax: (845) 365-8156 Fax: (508) 457-2193 Margaret Linek Guenter Suhr Logging Trainee Structural Geologist Angeandte Geophysik Mineralogisch-Petrographisches Institut Rheinisch-Westfälischen Technischen Hochschule Universität Köln Aachen Zülpicher Strasse 49b RW Technische Hochschule 50674 Köln Lochnerstrasse 4-20 Germany 52064 Aachen [email protected] Germany Work: (49) 221-470-3196 [email protected] Fax: (40) 221-470-5199 Work: (49) 241-809-4832 Masako Tominaga Fax: (49) 241-809-2132 Paleomagnetist Olivia U. Mason Department of Oceanography Microbiologist Texas A&M University College of Oceanography 3F Oceanography Building Oregon State University 3146 TAMU Giovannoni Laboratory College Station TX 77843-3146 104 COAS Administration Building USA Corvallis OR 97331-5503 [email protected] USA Work: (979) 845-7211 [email protected] Fax: (979) 845-6331 Work: (503) 939-1035 5 Expedition 305 Preliminary Report Toru Yamasaki Xixi Zhao Geochemist Paleomagnetist Department of Earth and Planetary Sciences Center for Study of Imaging and Dynamics Hokkaido University of the Earth Graduate School of Science Institute of Geophysics and Planetary Physics N 10, W 8 University of California, Santa Cruz Sapporo, Hokkaido 060-0810 Earth and Marine Sciences Building Japan 1156 High Street [email protected] Santa Cruz CA 95064 Work: (81) 11 716 2111, ext. 4655 USA Fax: (81) 11 746 0394 [email protected] Work: (831) 459-4847 Fax: (831) 459-3074 Expedition 304 Scientific Party Florence Einaudi Muriel Andreani Logging Staff Scientist Metamorphic Petrologist Laboratoire de Geophysique et D’hydrodynamique Laboratoire de Geosciences Marines Université Montpellier II, ISTEEM CNRS UMR 7097 Case Courrier 56 Institut de Physique du Globe de Paris 34095 Montpellier Cedex 5 4 Place Jussieu—Case 89 France 75252 Paris Cedex 5 [email protected] France Work: (33) 4-67-14-93-09 [email protected] Fax: (33) 4-67-14-93-08
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  • Babbitt Se.Indd

    Babbitt Se.Indd

    Prepared and Published with the Support of MISCELLANEOUS MAP SERIES THE U.S. GEOLOGICAL SURVEY AS PART OF THE 2004 STATE GEOLOGIC MAPPING PROGRAM ELEMENT (STATEMAP) MAP M-162 MINNESOTA GEOLOGICAL SURVEY OF THE NATIONAL GEOLOGIC MAPPING PROGRAM Bedrock Geology, Babbitt SE Quadrangle Harvey Thorleifson, Director �� ��� BEDROCK GEOLOGY OF THE BABBITT SOUTHEAST QUADRANGLE, ��� �� ��� ��� �� �� �� �� ST. LOUIS AND LAKE COUNTIES, MINNESOTA �� �� �� ��� �� By �� ��� �� ��� ��� �� �� James D. Miller, Jr. �� �� �� �� ��� 2005 �� �� ��� �� ��� �� �� ��� ������������������������ MAP SYMBOLS ����������� Geologic contact—Approximately located by outcrop control. ��� ��������� �� ��� ��������� Geologic contact—Poorly located by rare outcrop, topography, and/or ����������� �� ��� ����� geophysical data. ��������� �� ��� Fault—Inferred, based on geologic offset, topography, local structures, ��� �� ������� ��� ��� ����� and/or geophysical data. ��� ��� ������ ��� ��� ���������� Fault—Speculative, based on geophysical data and/or topography. ��� ��������� ������ Attitude of inclined sedimentary or volcanic bedding ��� ������� � ���������� �� �� Attitude of inclined igneous layering ��� ��� ��� ������ ��������� ��������������� Attitude of igneous foliation (inclined, horizontal) �� ��� Trend of igneous fabric ��� ��� ��� ��� ������������� Attitude of inclined bedding-parallel joint set ��� ��� ������ Attitude of vertical mineralized joint ��� �� �� �� Attitude of inclined felsic dike ��� ��� ��� Area of bedrock outcrop �� �� ��� ��� ����������� Drill hole
  • Implications for the Rheological Behavior of Oceanic Detachment Faults

    Implications for the Rheological Behavior of Oceanic Detachment Faults

    Article Volume 14, Number 8 28 August 2013 doi: 10.1002/ggge.20184 ISSN: 1525-2027 Mylonitic deformation at the Kane oceanic core complex: Implications for the rheological behavior of oceanic detachment faults Lars N. Hansen Department of Geological and Environmental Sciences, Stanford University, 450 Serra Mall, Building 320, Stanford, California, 94305, USA ([email protected]) Michael J. Cheadle, Barbara E. John, and Susan M. Swapp Department of Geology and Geophysics, University of Wyoming, Wyoming, USA Henry J. B. Dick, Brian E. Tucholke, and Maurice A. Tivey Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA [1] The depth extent, strength, and composition of oceanic detachment faults remain poorly understood because the grade of deformation-related fabrics varies widely among sampled oceanic core complexes (OCCs). We address this issue by analyzing fault rocks collected from the Kane oceanic core complex at 23300N on the Mid-Atlantic Ridge. A portion of the sample suite was collected from a younger fault scarp that cuts the detachment surface and exposes the interior of the most prominent dome. The style of deformation was assessed as a function of proximity to the detachment surface, revealing a 450 m thick zone of high-temperature mylonitization overprinted by a 200 m thick zone of brittle deformation. Geothermometry of deformed gabbros demonstrates that crystal-plastic deformation occurred at temperatures >700C. Analysis of the morphology of the complex in conjunction with recent thermochronology suggests that deformation initiated at depths of 7 km. Thus we suggest the detachment system extended into or below the brittle-plastic transition (BPT).