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1 University of New Hampshire University of New Hampshire Scholars' Repository Affiliate Scholarship Center for Coastal and Ocean Mapping 1992 Proceedings of the Ocean Drilling Program. VOLUME 13 8 INITIAL REPORTS PARTI EASTERN EQUATORIAL PACIFIC Covering Leg 138 of the cruises of the Drilling Vessel JOIDES Resolution, Balboa, Panama, to San Diego, California, Sites , 6 May July 1991 Larry A. Mayer University of New Hampshire, larry.mayer@unh.edu Nicklas G. Pisias Oregon State University Thomas R. Janecek Texas A & M University - College Station Jack G. Baldauf Texas A & M University - College Station Stephen F. Bloomer University of New Brunswick Recommended Citation Mayer, L.A., Pisias, N.P., and Janecek, T., 1992, Proceedings of the Ocean Drilling Program - Initial Reports: 138 College Station, Texas (Ocean Drilling Program) p. This Book is brought to you for free and open access by the Center for Coastal and Ocean Mapping at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Affiliate Scholarship by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact nicole.hentz@unh.edu.

2 See next page for additional authors Follow this and additional works at: Part of the Geology Commons, Geophysics and Seismology Commons, and the Oceanography and Atmospheric Sciences and Meteorology Commons

3 Proceedings of the Ocean Drilling Program. VOLUME 13 8 INITIAL REPORTS PARTI EASTERN EQUATORIAL PACIFIC Covering Leg 138 of the cruises of the Drilling Vessel JOIDES Resolution, Balboa, Panama, to San Diego, California, Sites , 6 May July 1991 Authors Larry A. Mayer, Nicklas G. Pisias, Thomas R. Janecek, Jack G. Baldauf, Stephen F. Bloomer, Kathleen A. Dadey, Kay-Christian Emeis, John Farrell, Jose Abel Flores, Eric M. Galimov, T. K. Hagelberg, Peter Holler, Stephen A. Hovan, Masao Iwai, Alan E. S. Kemp, Dae Choul Kim, Gary Klinkhammer, Margaret Leinen, Shaul Levi, Mikhail A. Levitan, Mitchell Lyle, Angus K. MacKillop, Laure M. Meynadier, Alan C. Mix, Ted C. Moore Jr, Isabella Raffi, Christina Ravelo, David Schneider, N. J. Shackleton, Jean-Pierre Valet, and Edith Vincent This book is available at University of New Hampshire Scholars' Repository:

4 PROCEEDINGS OF THE OCEAN DRILLING PROGRAM VOLUME 138 INITIAL REPORTS PARTI EASTERN EQUATORIAL PACIFIC Covering Leg 138 of the cruises of the Drilling Vessel JOIDES Resolution, Balboa, Panama, to San Diego, California, Sites , 6 May July 1991 Larry A. Mayer, Nicklas G. Pisias, Thomas R. Janecek, Jack Q. Baldauf, Steven F. Bloomer, Kathleen A. Dadey, Kay-Christian Emeis, John Farrell, José Abel Flores, Eric M. Galimov, Teresa King Hagelberg, Peter Holler, Steven A. Hovan, Masao Iwai, Alan E.S. Kemp, Dae Choul Kim, Gary Klinkhammer, Margaret Leinen, Shaul Levi, Mikhail A. Levitan, Mitchell W. Lyle, Angus K. MacKillop, Laure M. Meynadier, Alan C. Mix, Ted C. Moore, Jr., Isabella Raffi, Christina Ravelo, David Schneider, Nicholas J. Shackleton, Jean-Pierre Valet, Edith Vincent Shipboard Scientists Thomas R. Janecek Shipboard Staff Scientist Prepared by the OCEAN DRILLING PROGRAM TEXAS A&M UNIVERSITY Sondra K. Stewart, Diana Kennett, Norman J. Stewart, and William R. Winkler Volume Editors in cooperation with the NATIONAL SCIENCE FOUNDATION and JOINT OCEANOGRAPHIC INSTITUTIONS, INC.

5 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 was provided by the following agencies at the time of this cruise: Academy of Sciences (U.S.S.R.) Canada/Australia Consortium for the Ocean Drilling Program, Department of Energy, Mines and Resources (Canada) and Department of Primary Industries and Energy (Australia) Deutsche Forschungsgemeinschaft (Federal Republic of Germany) European Science Foundation Consortium for Ocean Drilling (Belgium, Denmark, Finland, Iceland, Italy, Greece, The Netherlands, Norway, Spain, Sweden, Switzerland, and Turkey) Institut Français de Recherche pour 1'Exploitation de la Mer (France) National Science Foundation (United States) Natural Environment Research Council (United Kingdom) University of Tokyo, Ocean Research Institute (Japan) 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. It is recommended that reference to the whole or to part of this volume be made in one of the following forms, as appropriate: Mayer, L., Pisias, N., Janecek, T., et al., Proc. ODP, Init. Repts. 138: College Station, TX (Ocean Drilling Program). Lyle, M., Composition maps of surface sediments of the eastern tropical Pacific Ocean. In Mayer, L., Pisias, N., Janecek, T., et al., Proc. ODP, Init. Repts. 138: College Station, TX (Ocean Drilling Program), Effective Publication Dates of ODP Proceedings According to the International Code of Zoological Nomenclature, the date of publication of a work and of a contained name or statement affecting nomenclature is the date on which the publication was mailed to subscribers, placed on sale, or when the whole edition is distributed free of charge, mailed to institutions and individuals to whom free copies are distributed. The mailing date, not the printed date, is the correct one. The mailing dates of recent Proceedings of the Ocean Drilling Program are as follows: Volume 134 {Initial Reports): March 1992 Volume 135 (Initial Reports): May 1992 Volumes 136/137 (Initial Reports): January 1992 Volume 120 (Scientific Results): April 1992 Volume 121 (Scientific Results): November 1991 Volume 122 (Scientific Results): February 1992 Distribution Copies of this publication may be obtained from Publications Distribution Center, Ocean Drilling Program, 1000 Discovery Drive, College Station, Texas Orders for copies will require advance payment. See current ODP publication list for price and availability of this publication. Printed September 1992 ISSN Library of Congress Printed in Canada by D.W. Friesen & Sons Ltd. The paper used in this publication meets the minimum requirements of American National Standard for Information Sciences Permanence of Paper for Printed Library Materials, ANSI Z < >

6 Foreword By the National Science Foundation The Ocean Drilling Program (ODP) is a major component of the National Science Foundation^ continuing commitment to the study of the geologic processes that have shaped our planet and modified its environment. The scientific problems being addressed range from the geologic history and structure of continental margins to the processes responsible for the formation and alteration of the ocean's crust. In a time of enhanced public and scientific interest in problems of global change, ODP provides critical data on changes in ocean circulation, chemistry, and biologic productivity and their relation to changes in atmospheric circulation and glacial conditions. The Ocean Drilling Program has a unique role in addressing these problems, since it is the only facility for continuously sampling the geologic record of the ocean basins, which cover 70% of our planet. The ODP is the successor to the Deep Sea Drilling Project (DSDP), which was a global reconnaissance of the ocean basins. DSDP began operations in 1968 at Scripps Institution of Oceanography, using a 400-foot drillship, the Glomar Challenger. DSDP was supported initially by only the National Science Foundation, with extensive involvement of international scientists who were invited to participate on drilling cruises. As this international interest continued to grow in the early 1970's, formal participation in the project was offered to the international geoscience community. In 1975, five nations (France, the Federal Republic of Germany, Japan, the United Kingdom, and the Soviet Union) accepted this commitment to joint planning and conduct of the project, as well as to financial support for operations. This International Phase of Ocean Drilling (IPOD) continued to Although the Challenger had reached the limits of her capabilities, the remarkable scientific success of the DSDP and the new questions it had generated demanded a continuing capability for drilling in the oceans. The Ocean Drilling Program was organized, international participation was coordinated, a new drillship (the JOIDES Resolution) was contracted and outfitted, and her first cruise sailed in early 1985, within 18 months of the retirement of the Challenger. This is a remarkable accomplishment that reflects the efforts and excellence of the Joint Oceanographic Institutions, Inc. (prime contractor for ODP), Texas A&M University (science and ship operator), Lamont-Doherty Geological Observatory (logging operator), and the international science community in organizing and planning the new program. It was argued in planning for the ODP that a larger drillship was required to provide space for the increasing U.S. and international demand for shipboard participation, improved and expanded laboratory capabilities, and improvements in coring and logging systems. A larger and better equipped vessel would also provide better stability and working conditions in high-latitude regions of the oceans. The success of the JOIDES Resolution has proven the wisdom of these early arguments. ODP now has operated in all oceans except the ice-covered Arctic. We have drilled above the Arctic circle and within sight of the Antarctic continent. Over 1000 scientists from 25 nations have participated in the initial ODP cruises. The larger scientific parties have allowed an increased emphasis on student participation and training aboard ship. The state-of-the-art laboratories support rapid and complete initial analyses of samples that provide both scientific results and guide subsequent shore-based studies. Nearly 1000 additional scientists have used these data and requested samples from the program's core and data archives for continuing study. The geochemical and geophysical logging capability is unsurpassed in either academia or industry and has provided remarkable new data with which to study the Earth. New experiments to measure and monitor geologic processes have been deployed in ODP boreholes. The international commitment to ocean drilling has increased in the ODP. In addition to our five partners in IPOD France, the Federal Republic of Germany, Japan, the Soviet Union, and the United Kingdom two consortia have joined ODP: Canada-Australia and the European Science Foundation (representing Belgium, Denmark, Finland, Greece, Iceland, Italy, The Netherlands, Norway, Spain, Sweden, Switzerland, and Turkey). The 20 countries of the ODP represent the community of nations that have a global interest in the geosciences and oceanography. This global scientific participation has assured the program's scientific excel-

7 lence by focusing and integrating the combined scientific knowledge and capabilities of the program's 20 nations. It has allowed problems of a global nature to be addressed by providing databases and background studies which are openly shared for planning and interpreting drilling results. It has eased problems of access to territorial waters, allowing comparative studies to be done among oceans. Finally, the international sharing of program costs has allowed this important and large program to proceed without detrimental impact to the research budgets of any one nation. The Ocean Drilling Program, like its predecessor, DSDP, serves as a model for planning, conducting, and financing research to address problems of global importance. The National Science Foundation is proud to have a leading role in this unique international program, and we look forward to its continuing success. Washington, D.C. Walter E. Massey Director National Science Foundation

8 Foreword By Joint Oceanographic Institutions, Inc. This volume presents scientific and engineering results from the Ocean Drilling Program (ODP). The papers presented here address the scientific and technical goals of the program, which include providing a global description of geological and geophysical structures including passive and active margins and sediment history, and studying in detail areas of major geophysical activity such as mid-ocean ridges and the associated hydrothermal circulations. The Ocean Drilling Program, an international activity, operates a specially equipped deep-sea drilling ship, the JOIDES Resolution (Sedco/BP All), which contains state-of-the-art laboratories, equipment, and computers. The ship is 471 feet (144 meters) long, is 70 feet (21 meters) wide, and has a displacement of 18,600 short tons. Her derrick towers 211 feet (64 meters) above the waterline, and a computer-controlled dynamic-positioning system stabilizes the ship over a specific location while drilling in water depths up to 27,000 feet (8230 meters). The drilling system collects cores from beneath the seafloor with a derrick and drawworks that can handle 30,000 feet (9144 meters) of drill pipe. More than 12,000 square feet (1115 square meters) of space distributed throughout the ship is devoted to scientific laboratories and equipment. The ship sails with a scientific and technical crew of 51 and a ship's crew (including the drill crew) of 62. The size and ice-strengthening of the ship allow drilling in high seas and ice-infested areas as well as permitting a large group of multidisciplinary scientists to interact as part of the scientific party. Logging, or measurements in the drilled holes, is an important part of the program. ODP provides a full suite of geochemical and geophysical measurements for every hole deeper than 1300 feet (400 meters). For each such hole, there are lowerings of basic oil-industry tools: nuclear, sonic, and electrical. In addition, a borehole televiewer is available for imaging the wall of the hole, a 12-channel logging tool provides accurate velocity and elastic property measurements as well as sonic waveforms for spectral analysis of energy propagation near the wall of the hole, and a vertical seismic profiler can record reflectors from below the total depth of the hole. The management of the Ocean Drilling Program involves a partnership of scientists and governments. International oversight and coordination are provided by the ODP Council, a governmental consultative body of the partner countries, which is chaired by a representative from the United States National Science Foundation. The ODP Council periodically reviews the general progress of the program and discusses financial plans and other management issues. Overall scientific and management guidance is provided to the operators of the program by representatives from the group of institutions involved in the program, called the Joint Oceanographic Institutions for Deep Earth Sampling (JOIDES). The Executive Committee (EXCOM), made up of the administrative heads of the JOIDES institutions, provides general oversight for ODP. The Planning Committee (PCOM), with its advisory structure, is made up of working scientists and provides scientific advice and detailed planning. PCOM has a network of panels and working groups that screen drilling proposals, evaluate instrumentation and measurement techniques, and assess geophysical-survey data and other safety and siting information. PCOM uses the recommendations of the panels and committees to select drilling targets, to specify the location and major scientific objectives of each two-month drilling segment or leg, and to provide the science operator with nominations for co-chief scientists. Joint Oceanographic Institutions, Inc. (JOI), a nonprofit consortium of U.S. Oceanographic institutions, serves as the National Science Foundation^ prime contractor for ODP. JOI is responsible for seeing that the scientific objectives, plans, and recommendations of the JOIDES committees are translated into scientific operations consistent with scientific advice and budgetary constraints. JOI subcontracts the operations of the program to two universities: Texas A&M University and Lamont-Doherty Geological Observatory of Columbia University. JOI is also responsible for managing the U.S. contribution to ODP. Texas A&M University (TAMU) serves as science operator for ODP. In this capacity, TAMU is responsible for planning the specific ship operations, actual drilling schedules, and final scientific rosters, which are developed in close cooperation with PCOM and the relevant

9 panels. The science operator also ensures that adequate scientific analyses are performed on the cores by maintaining the shipboard scientific laboratories and computers and by providing logistical and technical support for shipboard scientific teams. Onshore, TAMU manages scientific activities after each leg, is curator for the cores, distributes samples, and coordinates the editing and publication of scientific results. Lamont-Doherty Geological Observatory (LDGO) of Columbia University is responsible for the program's logging operation, including processing the data and providing assistance to scientists for data analysis. The ODP Data Bank, a repository for geophysical data, is also managed by LDGO. Core samples from ODP and the previous Deep Sea Drilling Project are stored for future investigation at three sites: ODP Pacific and Indian Ocean cores at TAMU, ODP and DSDP Atlantic and Antarctic cores at LDGO, and DSDP Pacific and Indian Ocean cores at the Scripps Institution of Oceanography. Scientific achievements of ODP include new information on early seafloor spreading and how continents separate and the margins evolve. The oldest Pacific crust has been drilled and sampled. We have new insights into glacial cycles and the fluctuations of ocean currents throughout geological time. Many of the scientific goals can be met only with new technology; thus the program has focused on engineering as well as science. To date, ODP engineers have demonstrated the capability to drill on bare rock at mid-ocean-ridge sites and have developed techniques for drilling in high-temperature and corrosive regions typical of hydrothermal vent areas. A new diamond coring system promises better core recovery in difficult areas. In addition, ODP is cooperating closely with other geological and geophysical programs; for example, in 1991 the first hole was drilled by ODP for emplacement of a seismometer near Hawaii for the Ocean Seismic Network. JOI is pleased to have been able to play a facilitating role in the Ocean Drilling Program and its cooperative activities, and we are looking forward to many new results to come. Washington, D.C. D. James Baker President Joint Oceanographic Institutions, Inc.

10 OCEAN DRILLING PROGRAM MEMBER ORGANIZATIONS OF THE JOINT OCEANOGRAPHIC INSTITUTIONS FOR DEEP EARTH SAMPLING (JOIDES): University of California at San Diego, Scripps Institution of Oceanography Columbia University, Lamont-Doherty Geological Observatory University of Hawaii, School of Ocean and Earth Science and Technology University of Miami, Rosenstiel School of Marine and Atmospheric Science Oregon State University, College of Oceanography University of Rhode Island, Graduate School of Oceanography Texas A&M University, College of Geosciences and Maritime Studies University of Texas at Austin, Institute for Geophysics University of Washington, College of Ocean and Fishery Sciences Woods Hole Oceanographic Institution Canada/Australia Consortium for the Ocean Drilling Program, Department of Energy, Mines and Resources (Canada) and Department of Primary Industries and Energy (Australia) European Science Foundation Consortium for Ocean Drilling, Belgium, Denmark, Finland, Iceland, Italy, Greece, The Netherlands, Norway, Spain, Sweden, Switzerland, and Turkey Federal Republic of Germany, Bundesanstalt für Geowissenschaften und Rohstoffe France, Institut Français de Recherche pour 1'Exploitation de la Mer Japan, University of Tokyo, Ocean Research Institute United Kingdom, Natural Environment Research Council Russia, Academy of Sciences OPERATING INSTITUTION College of Geosciences and Maritime Studies Texas A&M University College Station, Texas Robert A. Duce Dean OCEAN DRILLING PROGRAM Philip D. Rabinowitz Director Timothy J.G. Francis Deputy Director Richard G. McPherson Administrator Jack G. Baldauf, Manager Science Operations Barry W. Harding, Manager Engineering and Drilling Operations Russell B. Merrill, Curator and Manager Science Services Robert E. Olivas, Manager Technical and Logistics Support LOGGING OPERATOR Borehole Research Group Lamont-Doherty Geological Observatory Columbia University Palisades, New York Roger N. Anderson, Head PRIME CONTRACTOR Joint Oceanographic Institutions, Inc. Washington, D.C. Thomas E. Pyle Director, Ocean Drilling Programs

11 PARTICIPANTS ABOARD THE JOIDES RESOLUTION FOR LEG 138* Larry A. Mayer Co-Chief Scientist Department of Oceanography Dalhousie University Halifax, Nova Scotia B3H 4J1 Canada Nicklas G. Pisias Co-Chief Scientist Oceanography Administration Bldg. 104 College of Oceanography Oregon State University Corvallis, Oregon Thomas R. Janecek ODP Staff Scientist/Sedimentologist Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, Texas Jack G. Baldauf Paleontologist (diatoms) Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, Texas Steven F. Bloomer Physical Properties Specialist Department of Oceanography Dalhousie University Halifax, Nova Scotia B3H 4J1 Canada Kathleen A. Dadey Logging Scientist Hawaii Institute of Geophysics School of Ocean and Earth Science and Technology University of Hawaii 2525 Correa Road Honolulu, Hawaii Kay-Christian Emeis Organic Geochemist Geologisch-Palàontologisches Institut Universitat Kiel Olshausenstrasse D-2300 Kiel Federal Republic of Germany John Farrell Carbonate Geochemist Department of Geological Sciences Brown University Providence, Rhode Island José Abel Flores Paleontologist (nannofossils) Departamento de Geologia Universidad de Salamanca S Salamanca Spain Eric M. Galimov Organic Geochemist Institute of Geochemistry and Analytical Chemistry U.S.S.R. Academy of Sciences Ul. Kosygina 19 B-3 31, Moscow U.S.S.R. Teresa King Hagelberg Sedimentologist College of Oceanography Oregon State University Corvallis, Oregon Peter Holler Physical Properties Specialist Geologisch-Palàontologisches Institut Universitat Kiel Olshausenstrasse D-2300 Kiel Federal Republic of Germany Steven A. Hovan Sedimentologist Department of Geological Sciences University of Michigan 1006 C.C. Little Building Ann Arbor, Michigan Masao Iwai Paleontologist (diatoms) Institute of Geology and Paleontology Faculty of Science Tohoku University Aobayama, Aoba-ku Sendai 980 Japan Alan E.S. Kemp Sedimentologist Department of Oceanography The University Southampton SO9 5NH United Kingdom Dae Choul Kim Physical Properties Specialist Department of Applied Geology National Fisheries University ofpusan Daeyeon-Dong, NamGum Pusan Korea *Addresses at time of cruise.

12 Gary Klinkhammer Inorganic Geochemist College of Oceanography Oregon State University Corvallis, Oregon Margaret Leinen Sedimentologist Graduate School of Oceanography University of Rhode Island Kingston, Rhode Island Shaul Levi Paleomagnetist College of Oceanography Oregon State University Corvallis, Oregon Mikhail A. Levitan Sedimentologist P.P. Shirshov Institute of Oceanology U.S.S.R. Academy of Sciences 23 Krasikova Str. Moscow USSR. Mitchell W. Lyle LDGO Logging Scientist Borehole Research Group Lamont-Doherty Geological Observatory Columbia University Palisades, New York Angus K. MacKillop Physical Properties Specialist Center for Water Resources Technical University of Nova Scotia P.O. Box 1000 Halifax, Nova Scotia B3J 2X4 Canada Laure M. Meynadier Physical Properties Specialist Institut de Physique du Globe Université Pierre et Marie Curie 4 Place Jussieu, Tour Paris Cedex 05 France Alan C. Mix Sedimentologist College of Oceanography Oregon State University Corvallis, Oregon Ted C. Moore, Jr. Paleontologist (radiolarians) Center for Great Lakes and Aquatic Sciences University of Michigan 2200 Bonisteel Boulevard Ann Arbor, Michigan Isabella Raffi Paleontologist (nannofossils) Universita di Parma do Servizio Geologico Nazionale Largo S. Susanna Roma Italy Christina Ravelo Sedimentologist Program in Atmospheric and Oceanic Sciences Princeton University P.O. Box CN 710, Sayre Hall Princeton, New Jersey David Schneider Paleomagnetist Lamont-Doherty Geological Observatory Columbia University Palisades, New York Nicholas J. Shackleton Paleontologist (foraminifers)/stratigraphic Correlator Subdepartment of Quaternary Research Godwin Laboratory University of Cambridge Free School Lane Cambridge CB2 3RS United Kingdom Jean-Pierre Valet Paleomagnetist Institut de Physique du Globe Université Pierre et Marie Curie 4 Place Jussieu, Tour Paris Cedex 05 France Edith Vincent Paleontologist (foraminifers) Département de Géologie Dynamique Université Pierre et Marie Curie 4 Place Jussieu, Tour Paris Cedex 05 France SEDCO OFFICIALS Captain Anthony Ribbens Master of the Drilling Vessel Underseas Drilling, Inc. 707 Texas Avenue South Suite 103D College Station, Texas Jack Tarbutton Drilling Superintendent Underseas Drilling, Inc. 707 Texas Avenue South Suite 103D College Station, Texas

13 ODP ENGINEERING AND OPERATIONS PERSONNEL Ron Grout Operations Superintendent ODP TECHNICAL AND LOGISTICS PERSONNEL Wendy J. Autio John W. Beck Daniel Bontempo Jim Briggs Timothy Bronk Jo Claesgens Valerie Clark Bradley Cook John R. Eastlund Mark Gilmore Burney Hamlin Gretchen Hampt Sung-Ho Kang Jon S. Lloyd Cynthia M. Lyle Eric Meissner William M. Meyer John H. Miller X-ray Technician Photographer Marine Scientist Electronics Technician Marine Scientist Yeoperson Chemistry Technician Marine Scientist Computer System Manager Photographer Laboratory Officer Chemistry Technician Marine Scientist Marine Scientist Marine Scientist Electronics Technician Assistant Laboratory Officer Curatorial Representative Ocean Drilling Program Publications Staff Publications Supervisor William D. Rose ChiefEditor Norman J. Stewart Editors Lona Haskins Dearmont Eva M. Maddox Sondra K. Stewart William R. Winkler Bibliographer Nancy K. McQuistion (part-time) Chief Production Editor Jennifer Pattison Hall Production Editors Janna C. Abel (this volume) Jill K. Butler Jaime A. Gracia Senior Publications Coordinator Janalisa Braziel Soltis Publications Coordinator Gudelia ("Gigi") Delgado Publications Distribution Specialist Fabiola Mufioz Byrne Hole Summary Coordinator Laura Hammond Young Data Entry/Copier Operator Carrie Jo Parris Senior Photographer John W. Beck Photographer Barry C. Cochran Chief Illustrator Deborah L. Partain Illustrators Melany R. Borsack Michelle Curtis Linda C. De Leon Garnet D. Gaither Lisa L. Tirey Production Assistants Mary Elizabeth Betz Carrie R. Castillón

14 TABLE OF CONTENTS VOLUME 138 INITIAL REPORTS (Part 1) Acknowledgments 1 SECTION 1: INTRODUCTION 1. Introduction 5 Shipboard Scientific Party 2. Explanatory notes 13 Shipboard Scientific Party 3. Underway geophysics 43 S. F. Bloomer and Shipboard Scientific Party SECTION 2: SPECIAL CHAPTERS 4. Color reflectance spectroscopy: a tool for rapid characterization of deep sea sediments 67 A. C. Mix, W. Rugh, N. G. Pisias, S. Veirs, Leg 138 Shipboard Sedimentologists (T. Hagelberg, S. Hovan, A. Kemp, M. Leinen, M. Levitan, and C. Ravelo), and the Leg 138 Scientific Party 5. Development of composite depth sections for Sites 844 through T. Hagelberg, N. Shackleton, N. Pisias, and Shipboard Scientific Party 6. Sedimentation rates: toward a GRAPE density stratigraphy for Leg 138 carbonate sections N. J. Shackleton and Shipboard Scientific Party 7. Site surveys 93 L. A. Mayer, N. G. Pisias, A. C. Mix, M. W. Lyle, P. Arason, and D. Mosher 8. Composition maps of surface sediments of the eastern tropical Pacific Ocean 101 M. Lyle SECTION 3: SITE CHAPTERS 9. Site Shipboard Scientific Party Site summary 119 Principal results 119 Background and scientific objectives 120 Operations 120 Lithostratigraphy 122 Biostratigraphy 131 Paleomagnetism 142 Sedimentation rates 145 Inorganic geochemistry 147 Organic geochemistry 148 Physical properties 153 Downhole measurements 159

15 Seismic stratigraphy 162 Summary and conclusions 163 References Site Shipboard Scientific Party Site summary 189 Principal results 189 Background and scientific objectives 190 Operations 190 Lithostratigraphy 191 Biostratigraphy 208 Paleomagnetism 216 Sedimentation rates 216 Inorganic geochemistry 220 Organic geochemistry 228 Physical properties 230 Downhole measurements 232 Seismic stratigraphy 236 Summary and conclusions 240 References Site Shipboard Scientific Party Site summary 265 Principal results 265 Background and scientific objectives 267 Operations 267 Lithostratigraphy 268 Biostratigraphy 285 Paleomagnetism 293 Sedimentation rates 293 Inorganic geochemistry 295 Organic geochemistry 300 Physical properties 304 Downhole measurements 307 Seismic stratigraphy 311 Summary and conclusions 313 References Site Shipboard Scientific Party

16 Site summary 335 Principal results 335 Background and scientific objectives 336 Operations 336 Lithostratigraphy 338 Biostratigraphy 346 Paleomagnetism 352 Sedimentation rates 353 Inorganic geochemistry 353 Organic geochemistry 357 Physical properties 359 Downhole measurements 362 Seismic stratigraphy 370 Summary and conclusions 372 References 374 SECTION 4: CORES Core description forms and core photographs for: Site Site Site Site SECTION 5: SMEAR SLIDES Smear slide descriptions for: Site Site Site Site Back-Pocket Foldout* Chapter 5, Figure 6. Comparison of GRAPE density records with downhole density logs. Chapter 6, Figure 1. GRAPE density records for Sites 844 through 854 vs. depth. Chapter 9, Figure 26. Percentage of reflectance, GRAPE density, and magnetic susceptibility for Site 844. Chapter 10, Figure 34. Percentage of reflectance, GRAPE density, and magnetic susceptibility for Site 845. Chapter 11, Figure 21. Percentage of reflectance, GRAPE density, and magnetic susceptibility for Site 846. Chapter 12, Figure 19. Percentage of reflectance, GRAPE density, and magnetic susceptibility for Site 847. *Back-pocket foldout, microfiche, and CD-ROM data are found in the back of Part 2.

17 Back-Pocket Microfiche* Formation Microscanner images: Hole 844B: Pass 1, scale 1:40, depth range mbsf Hole 844B: Pass 1, scale 1:6, depth range mbsf Hole 845B: Pass 2, scale 1:40, depth range mbsf Hole 845B: Pass 2, scale 1:6, depth range mbsf Hole 846B: Pass 2, scale 1:40, depth range mbsf Hole 846B: Pass 2, scale 1:6, depth range mbsf Hole 847B: Pass 1, scale 1:40, depth range mbsf Hole 847B: Pass 1, scale 1:6, depth range mbsf CD-ROM Data* The CD-ROM in the back of Part 2 of this volume contains more than 500 MB of data collected during Leg 138. The data are subdivided into four main directories: TABLES, CORE DATA, SITE DATA, and PROGRAMS. A README file on the CD-ROM contains detailed information about each of these directories. The TABLES directory contains many of the tables listed in the text (e.g., tables containing site sedimentation-rate data), as well as many tables only referenced in the text (e.g., tables containing site index-property data). A listing of the tables in this directory is found below and in the Table of Contents for Part 2. The CORE DATA directory contains the basic ODP information associated with each recovered core (e.g., Site, Hole, Core, Core type, etc.), as well as the nominal ODP depth (in mbsf) and the composite depth (in mcd). The SITE DATA directory contains data specific to a site. Each site directory contains at least five subdirectories: GRAPE density data, magnetic susceptibility data, color reflectance data, physical properties data, and geochemistry data. If downhole measurements were performed at the site, these data are stored in a sixth directory. In addition, the SITE DATA directory contains age-depth data and other data files that contain the information needed to construct composite sections for each site. The PROGRAMS directory contains four computer programs (in FORTRAN-77) that were developed by Leg 138 scientists and were used extensively on UNIX-based workstations during Leg 138. While these programs are not intended to be used directly from the CD-ROM, they do provide the numerical procedures used to process data during the leg and the numerical strategy used to generate the composite depth section at each site. For help with using these programs, please approach their authors. CD-ROM Tables* Chapter 6: Table 1. GRAPE density events for Sites 846 through 853. Table 2. Sedimentation rates based on data in Table 1. Table 3. GRAPE density events from Table 1 and depths estimated for the equivalent events. Table 4. Sedimentation rates based on data in Table 3. Chapter 9: Table 1. Summary of coring operations at Site 844. Table 3. Interval and depth constraints of nannofossil events. Table 4. Interval and depth constraints of foraminifer events. Table 5. Interval and depth constraints of radiolarian events. Table 6. Interval and depth constraints of diatom events. Table 10. Reversal boundary depths from Site 844. *Back-pocket foldout, microfiche, and CD-ROM data are found in the back of Part 2.

18 Table 11. Depths of top and bottom of each core in composite depth section. Table 12. Control points for accumulation rates. Table 13. Interstitial-water geochemical data for Holes 844A and 844B. Table 14. Percentages of total carbon, inorganic carbon, calcium carbonate, organic carbon, and nitrogen. Table 16. Average values of sedimentary parameters. Table 17. Index properties data from Site 844. Table 18. Compressional-wave velocity data. Table 19. Vane shear strength data. Table 20. Thermal conductivity data. Table 22. Summary of traveltimes, depths, and ages for reflectors. Chapter 10: Table 1. Summary of coring operations at Site 845. Table 3. Sample and depth constraints of nannofossil events. Table 4. Sample and depth constraints of radiolarian events. Table 5. Sample and depth constraints of diatom events. Table 8. Reversal boundary depths from Site 845. Table 9. Depths of top and bottom of each core in composite depth section. Table 10. Control points for accumulation rates. Table 11. Interstitial water geochemical data for Holes 845A and 845C. Table 12. Percentages of total carbon, inorganic carbon, carbonate, organic carbon, and nitrogen. Table 14. Average values of sedimentary parameters. Table 16. Index properties data from Site 845. Table 17. Compressional-wave velocity data. Table 18. Vane shear strength data. Table 19. Thermal conductivity data. Table 24. Summary of traveltimes, depths, and ages for reflectors. Chapter 11: Table 1. Coring summary for Site 846. Table 3. Sample and depth constraints of nannofossil events. Table 4. Sample and depth constraints of foraminifer events. Table 5. Sample and depth constraints of radiolarian events. Table 6. Sample and depth constraints of diatom events. Table 7. Depths of top and bottom of each core in composite depth section. Table 8. Control points for accumulation rates. Table 9. Interstitial-water geochemical data for Holes 846A and 846C. Table 10. Percentages of total carbon, inorganic carbon, carbonate, organic carbon, and nitrogen. Table 12. Average value of sedimentary parameters. Table 13. Concentrations of hydrocarbons in headspace volumes. Table 14. Results of ketone analyses, percentages of organic carbon and carbonate, and age estimates of samples. Table 15. Wet- and dry-bulk density, grain density, porosity, wet and dry water content, and void ratio data. Table 16. Compressional-wave velocity data. Table 17. Undrained shear strength data. Table 18. Thermal conductivity data. Table 20. Summary of traveltimes, depths, and ages for reflectors. Chapter 12: Table 1. Summary of coring operations at Site 847. Table 3. Sample and depth constraints of nannofossil events. Table 4. Sample and depth constraints of foraminifer events.

19 Table 5. Sample and depth constraints of radiolarian events. Table 6. Sample and depth constraints of diatom events. Table 7. Depths of top and bottom of each core in composite depth section. Table 8. Control points for accumulation rates. Table 9. Interstitial-water geochemical data for Holes 847A and 847B. Table 10. Percentages of total carbon, inorganic carbon, carbonate, and organic carbon. Table 12. Average values of sedimentary parameters. Table 13. Concentrations of total carbon, inorganic carbon, organic carbon, total nitrogen, and total methane. Table 14. Wet- and dry-bulk density, grain density, porosity, wet and dry water content, and void ratio data. Table 15. Compressional-wave velocity data. Table 16. Vane shear strength velocity data. Table 17. Thermal conductivity data. Table 21. Summary of traveltimes, depths, and ages for reflectors.

20 TABLE OF CONTENTS VOLUME 138 INITIAL REPORTS (PART 2) SECTION 6: SITE CHAPTERS 13. Site Shipboard Scientific Party Site summary 677 Principal results 677 Background and scientific objectives 678 Operations 678 Lithostratigraphy 680 Biostratigraphy 685 Paleomagnetism 692 Sedimentation rates 695 Inorganic geochemistry 698 Organic geochemistry 703 Physical properties 704 Downhole measurements 705 Seismic stratigraphy 711 Summary and conclusions 712 References Site Shipboard Scientific Party Site summary 735 Principal results 735 Background and scientific objectives 736 Operations 736 Lithostratigraphy 740 Biostratigraphy 744 Paleomagnetism 748 Sedimentation rates 748 Inorganic geochemistry 749 Organic geochemistry 752 Physical properties 754 Downhole measurements 756 Seismic stratigraphy 762 Summary and conclusions 763 References 766

21 15. Site Shipboard Scientific Party Site summary 809 Principal results 809 Background and scientific objectives 810 Operations 810 Lithostratigraphy 811 Biostratigraphy 817 Paleomagnetism 825 Sedimentation rates 830 Inorganic geochemistry 830 Organic geochemistry 843 Physical properties 843 Downhole measurements 844 Seismic stratigraphy 848 Summary and conclusions 849 References Site Shipboard Scientific Party Site summary 891 Principal results 892 Background and scientific objectives 892 Operations 892 Lithostratigraphy 895 Biostratigraphy 903 Paleomagnetism 909 Sedimentation rates 913 Inorganic geochemistry 917 Organic geochemistry 921 Physical properties 922 Downhole measurements 926 Seismic stratigraphy 930 Summary and conclusions 931 References Site Shipboard Scientific Party Site summary 967 Principal results 967 Background and scientific objectives 968 Operations 968

22 Lithostratigraphy 970 Biostratigraphy 980 Paleomagnetism 986 Sedimentation rates 987 Inorganic geochemistry 990 Organic geochemistry 996 Physical properties 997 Downhole measurements 999 Seismic stratigraphy 1002 Summary and conclusions 1005 References Site Shipboard Scientific Party Site summary 1023 Principal results 1024 Background and scientific objectives 1024 Operations 1024 Lithostratigraphy 1026 Biostratigraphy 1029 Paleomagnetism 1032 Sedimentation rates 1035 Inorganic geochemistry 1036 Organic geochemistry 1042 Physical properties 1042 Seismic stratigraphy 1045 Summary and conclusions 1046 References Site Shipboard Scientific Party Site summary 1063 Principal results 1063 Background and scientific objectives 1064 Operations 1064 Lithostratigraphy 1064 Biostratigraphy 1068 Paleomagnetism 1073 Sedimentation rates 1079 Inorganic geochemistry 1081 Organic geochemistry 1083

23 Physical properties 1083 Summary and conclusions 1085 References 1090 SECTION 7: SUMMARY AND CONCLUSIONS 20. The planning and execution of a high-resolution paleoceanographic drilling leg: a summary Shipboard Scientific Party Goals 1095 Objectives 1095 Preliminary results 1095 SECTION 8: CORES Core description forms and core photographs for: Site Site Site Site Site Site Site SECTION 9: SMEAR SLIDES Smear slide descriptions for: Site Site Site Site Site Site Site SECTION 10: POLICY JOIDES Advisory Groups 1457 Sample-Distribution Policy 1461

24 Back-Pocket Foldout* Chapter 13, Figure 24. Magnetic susceptibility, GRAPE density, and percentage of reflectance for Site 848. Chapter 14, Figure 20. GRAPE density and percentage of reflectance for Site 849. Chapter 15, Figure 25. Magnetic susceptibility, GRAPE density, and percentage of reflectance for Site 850. Chapter 16, Figure 25. Magnetic susceptibility, GRAPE density, and percentage of reflectance for Site 851. Chapter 17, Figure 21. Magnetic susceptibility, GRAPE density, and percentage of reflectance for Site 852. Chapter 18, Figure 18. Magnetic susceptibility, GRAPE density, and percentage of reflectance for Site 853. Chapter 19, Figure 18. Magnetic susceptibility, GRAPE density, and percentage of reflectance for Site 854. Back-Pocket Microfiche* Formation Microscanner images: Hole 849B: Pass 2, scale 1:40, depth range mbsf Hole 849B: Pass 2, scale 1:6, depth range mbsf Hole 850B: Pass 2, scale 1:40, depth range mbsf Hole 850B: Pass 2, scale 1:6, depth range mbsf Hole 851B: Pass 2, scale 1:40, depth range mbsf Hole 851B: Pass 2, scale 1:6, depth range mbsf CD-ROM Data* The CD-ROM in the back of Part 2 of this volume contains more than 500 MB of data collected during Leg 138. The data are subdivided into four main directories: TABLES, CORE DATA, SITE DATA, and PROGRAMS. A README file on the CD-ROM contains detailed information about each of these directories. The TABLES directory contains many of the tables listed in the text (e.g., tables containing site sedimentation-rate data), as well as many tables only referenced in the text (e.g., tables containing site index-property data). A listing of the tables in this directory is found below and in the Table of Contents for Part 1. The CORE DATA directory contains the basic ODP information associated with each recovered core (e.g., Site, Hole, Core, Core type, etc.), as well as the nominal ODP depth (in mbsf) and the composite depth (in mcd). The SITE DATA directory contains data specific to a site. Each site directory contains at least five subdirectories: GRAPE density data, magnetic susceptibility data, color reflectance data, physical properties data, and geochemistry data. If downhole measurements were performed at the site, these data are stored in a sixth directory. In addition, the SITE DATA directory contains age-depth data and other data files that contain the information needed to construct composite sections for each site. The PROGRAMS directory contains four non-odp computer programs (in FORTRAN-77) that were used extensively at UNIX-based workstations during Leg 138. While these programs are not intended to be used directly from the CD-ROM, they do provide the numerical procedures used to process data during the leg and the numerical strategy used to generate the composite depth section at each site. Chapter 13: CD-ROM Tables* Table 1. Summary of coring operations at Site 848. Table 3. Sample and depth constraints of nannofossil events for Site 848. Table 4. Sample and depth constraints of radiolarian events for Site 848. Table 5. Sample and depth constraints of diatom events for Site 848. Table 7. Reversal boundary depths from Site 848. *Back-pocket foldout, microfiche, and CD-ROM data are found in the back of Part 2.

25 Table 8. Top and bottom depths of each core in Site 848 composite depth section. Table 9. Control points for accumulation rates. Table 10. Interstitial-water geochemical data for Holes 848A and 848B. Table 12. Bulk-sediment major oxide composition from X-ray fluorescence spectroscopy and loss on ignition in sediments from Hole 848C. Table 13. Comparison of X-ray fluorescence normative CaCO 3 with coulometric CaCO 3 measurements. Table 14. Elemental composition in bulk sediments and on a carbonate-free basis. Table 15. Mass accumulation rates for selected elements and for opal. Table 16. Average values of sedimentary parameters calculated over time intervals defined by chronostratigraphic levels. Table 17. Mean values of percentages of total carbon, inorganic carbon, calcium carbonate, and organic carbon for each sample analyzed at Site 848. Table 20. Index properties data from Site 848. Table 21. Compressional-wave velocity data from Site 848. Table 22. Vane shear strength data from Site 848. Table 23. Thermal conductivity data from Site 848. Chapter 14: Table 1. Summary of coring operations. Table 3. Sample and depth constraints of nannofossil events for Site 849. Table 4. Sample and depth constraints of foraminifer events for Site 849. Table 5. Sample and depth constraints of radiolarian events for Site 849. Table 6. Sample and depth constraints of diatom events for Site 849. Table 7. Depths of top and bottom of each core in Site 849 composite depth section. Table 8. Control points for sedimentation rates. Table 9. Interstitial-water geochemical data for Holes 849A and 849B. Table 10. Mean values of percentages of total carbon, inorganic carbon, calcium carbonate, and organic carbon for each sample analyzed at Site 849. Table 12. Average values of sedimentary parameters calculated over time intervals defined by chronostratigraphic levels. Table 13. Concentrations of methane in samples from Hole 849A. Table 14. Index properties data for Site 849. Table 15. Compressional-wave velocity data for Site 849. Table 16. Thermal conductivity data for Site 849. Table 17. Vane shear strength data for Site 849. Table 21. Summary of traveltimes, depths, and ages for Site 849 reflectors. Chapter 15: Table 1. Summary of coring operations at Site 850. Table 3. Sample and depth constraints of nannofossil events for Site 850. Table 4. Sample and depth constraints of foraminifer events for Site 850. Table 5. Sample and depth constraints of radiolarian events for Site 850. Table 6. Sample and depth constraints of diatom events for Site 850. Table 8. Reversal boundary determinations. Table 9. Depths of top and bottom of each core in Site 850 composite depth section. Table 10. Control points for sedimentation rates. Table 11. Interstitial-water geochemical data for Holes 850A and 850B. Table 12. Concentrations of SiO 2, A1 2 O 3, Fe 2 O 3, MnO, CaO, Na 2 O, K 2 O, and P 2 O 5 in ignited sediments from Site 850. Table 13. Concentrations of SiO 2, A1 2 O 3, Fe 2 O 3, MnO, CaO, Na 2 O, K 2 O, and P 2 O 5 in ignited sediments from Site 850 recalculated assuming all loss on ignition is CO 2 driven off CaCO 3. Table 14. Accumulation rates of SiO 2, Al 2 O 3, Fe 2 O 3, MnO, P 2 O 5, and biogenic silica (opal). Table 15. Average values of sedimentary parameters calculated over time intervals defined by chronostratigraphic levels.

26 Table 16. Mean values of percentages of inorganic carbon, calcium carbonate, and organic carbon for eachsample analyzed at Site 850. Table 17. Duplicate analyses of percentages of calcium carbonate in samples from Site 850. Table 18. Concentrations of methane in samples from Hole 850B. Table 19. Index properties data for Site 850. Table 20. Compressional-wave velocity data for Site 850. Table 21. Vane shear strength data for Site 850. Table 22. Thermal conductivity data for Site 850. Table 24. Summary of traveltimes, depths, and ages for Site 850 reflectors. Chapter 16: Table 1. Summary of coring operations at Site 851. Table 3. Sample and depth constraints of nannofossil events for Hole 851B. Table 4. Sample and depth constraints of foraminifer events for Hole 851B. Table 5. Sample and depth constraints of radiolarian events for Site 851. Table 6. Sample and depth constraints of diatom events for Site 851. Table 8. Reversal boundary depths from Site 851. Table 9. Depths of top and bottom of each core in Site 851 composite depth section. Table 10. Control points for sedimentation rates. Table 11. Interstitial-water geochemical data for Holes 851A and 851B. Table 12. Mean values of percentages of inorganic carbon, calcium carbonate, and organic carbon for each sample analyzed at Site 851. Table 14. Average values of sedimentary parameters calculated over time intervals defined by chronostratigraphic levels. Table 15. Concentrations of methane in samples from Hole 851B. Table 16. Index properties data for Site 851. Table 17. Compressional-wave velocity data for Site 851. Table 18. Vane shear strength data for Site 851. Table 19. Thermal conductivity data for Site 851. Table 22. Summary of traveltimes, depths, and ages for Site 851 reflectors. Chapter 17: Table 1. Summary of coring operations at Site 852. Table 4. Sample interval, ODP depth, and composite depth constraints of nannofossil events for Holes 852B, 852C, and 852D. Table 5. Sample interval, ODP depth, and composite depth constraints of foraminifer events for Hole 852B. Table 6. Sample interval, ODP depth, and composite depth constraints of radiolarian events for Holes 852B, 852C, and 852D. Table 7. Sample interval, ODP depth, and composite depth constraints of diatom events for Holes 852B, 852C, and 852D. Table 9. Reversal boundary depths from Site 852. Table 10. Depths of top and bottom of each core in Site 852 composite depth section. Table 11. Control points for sedimentation rates at Site 852. Table 12. Interstitial-water geochemical data for Holes 852A, 852B, and 852C. Table 13. Mean values of percentages of total carbon, inorganic carbon, calcium carbonate, and organic carbon for each sample analyzed at Site 852. Table 15. Average values of sedimentary parameters calculated over time intervals defined by chronostratigraphic levels in Table 11. Table 16. Index properties data for Site 852. Table 17. Compressional-wave velocity data for Site 852. Table 18. Vane shear strength data for Site 852. Table 19. Thermal conductivity data for Site 852. Table 21. Summary of traveltimes, depths, and ages for Site 852 reflectors.