Early Explorations of North Atlantic-Arctic GatewaysEarly exploration of the Arctic seas and coastlines was conducted as part of commercial whaling and trade operations. The map byWilliam Blaeu, "Regiones sub Polo Arctico," printed in 1649 in Amsterdam, did not yet display the coastlines of northeasternGreenland and of the eastern part of Svalbard. Blaeu had no clear conception of the Fram Strait and considered Baffin Bay closed to theNorth without the Nares Strait between northwestern Greenland and the Canadian Arctic archipelago. Other Arctic coastlines were onlyvaguely known. The map "Poli Arctici" by Hondius, printed in approximately 1680, also in Amsterdam, depicts a similar geographicsetting. The modern bathymetry, above, is given to provide a physiographic framework of the Leg 151 drill sites and for comparisonwith the older maps.

PROCEEDINGSOF THE

OCEAN DRILLINGPROGRAM

, ' ."- .."'.v,"* ! ' « • • *

VOLUME 151

SCIENTIFIC RESULTSNORTH ATLANTIC—ARCTIC GATEWAYS I

Covering Leg 151 of the cruises of the Drilling Vessel JOIDES Resolution,St. John's Harbor, Newfoundland, to Reykjavik, Iceland, Sites 907-913,

24 July-24 September 1993

Jörn Thiede, Annik M. Myhre, John V. Firth,Naokazu Ahagon, Kevin S. Black, Jan Bloemendal, Qarrett W. Brass,

James F. Bristow, Nancy Chow, Michel Cremer, Linda Davis, Benjamin Flower, Torben Fronval,Julie Hood, Donna Hull, Nalàn Koç, Birger Larsen, Mitchell W. Lyle, Jerry McManus,

Suzanne 0'Connell, Lisa Ellen Osterman, Frank R. Rack, Tokiyuki Sato, Reed P. Scherer,Dorothee Spiegler, Rüdiger Stein, Mark Tadross, Stephen Wells, David Williamson,

Bill Witte, Thomas Wolf-WellingShipboard Scientists

John V. FirthShipboard Staff Scientist

Editorial Review Board:Jörn Thiede, Annik M. Myhre, John V. Firth, Q.L. Johnson, W.F. Ruddiman

Prepared by theOCEAN DRILLING PROGRAM

TEXAS A&M UNIVERSITY

Ruth N. RiegelVolume Editor

in cooperation with theNATIONAL SCIENCE FOUNDATION

andJOINT OCEANOGRAPHIC INSTITUTIONS, INC.

This publication was prepared by the Ocean Drilling Program, Texas A&M University, as an accountof work performed under the international Ocean Drilling Program, which is managed by JointOceanographic Institutions, Inc., under contract with the National Science Foundation. Funding forthe program was provided by the following agencies at the time of this cruise:

Canada/Australia Consortium for the Ocean Drilling Program, Department of Energy, Mines andResources (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, Greece,Iceland, Italy, 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 thoseof the author(s) and do not necessarily reflect the views of the National Science Foundation, the par-ticipating agencies, Joint Oceanographic Institutions, Inc., Texas A&M University, or Texas A&MResearch Foundation.

Reference to the whole or to part of this volume should be made as follows:

Print citation:

Thiede, J., Myhre, A.M., Firth, J.V., Johnson, G.L., and Ruddiman, W.F. (Eds.), 1996. Proc. ODP,Sci. Results, 151: College Station, TX (Ocean Drilling Program).

Thiede, J., and Myhre, A.M., 1996. Introduction to the North Atlantic-Arctic Gateways: plate tec-tonic-paleoceanographic history and significance. In Thiede, J., Myhre, A.M., Firth, J.V.,Johnson, G.L., and Ruddiman, W.F. (Eds.), Proc. ODP, Sci. Results, 151: College Station, TX(Ocean Drilling Program), 3-23.

Electronic citation:

Thiede, J., Myhre, A.M., Firth, J.V., Johnson, G.L., and Ruddiman, W.F. (Eds.), 1996. Proc. ODP,Sci. Results [CD-ROM], 151: College Station, TX (Ocean Drilling Program).

Thiede, J., and Myhre, A.M., 1996. Introduction to the North Atlantic-Arctic Gateways: plate tec-tonic-paleoceanographic history and significance. In Thiede, J., Myhre, A.M., Firth, J.V.,Johnson, G.L., and Ruddiman, W.F. (Eds.), Proc. ODP, Sci. Results [CD-ROM], 151: CollegeStation, TX (Ocean Drilling Program), 3-23.

Effective Publication Dates of ODP Proceedings

According to the International Code of Zoological Nomenclature, the date of publication of a workand of a contained name or statement affecting nomenclature is the date on which the publicationwas 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 theprinted date, is the correct one.

The mailing dates of recent Proceedings of the Ocean Drilling Program are as follows:

Volume 161 {Initial Reports): June 1996Volume 162 {Initial Reports): September 1996Volumes 163/164 {Initial Reports): November 1996Volume 148 {Scientific Results): April 1996Volume 149 {Scientific Results): April 1996Volume 150 {Scientific Results): September 1996

Distribution

Copies of this publication may be obtained from Publications Distribution Center, Ocean Drilling Pro-gram, 1000 Discovery Drive, College Station, Texas 77845-9547, U.S.A. Orders for copies will requireadvance payment. See current ODP publication list for price and availability of this publication.

Printed December ,1996

ISSN 0884-5891Library of Congress 87-642-462

Printed in Canada by Friesens

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 Z39.48-1984 ™

ForewordBy the National Science Foundation

The National Science Foundation is proud to play a leading role in partnership with theU.S. oceanographic community in the operation and management of the Ocean DrillingProgram (ODP). We are equally proud of the cooperation and commitment of our interna-tional partners, who contribute both financial and intellectual resources required to main-tain the high quality of this unique program. The Ocean Drilling Program, like itspredecessor, the Deep Sea Drilling Project (DSDP), is a model for the organization andplanning of research to address global scientific problems that are of high priority interna-tionally and of long-term interest to the scientific community and general public.

Major scientific themes guiding the development of specific drilling cruises range fromdetermining the causes and effects of oceanic and climatic variability to understanding thecirculation of fluids in the ocean crust and the resultant formation of mineral deposits.Although such studies are at the forefront of basic scientific inquiry into the processes thatcontrol and modify the global environment, they are equally important in providing thebackground for assessing man's impact on the global environment or for projectingresource availability for future generations.

The transition from the DSDP to the ODP was marked by a number of changes. The471-foot JOIDES Resolution, which replaced the Glomar Challenger, has allowed largerscientific parties and the participation of more graduate students, a larger laboratory andtechnical capability, and operations in more hostile ocean regions. The JOIDES Resolu-tion has drilled in all of the world's oceans, from the marginal ice regions of the Arctic towithin sight of the Antarctic continent. Over 1,200 scientists and students from 26 nationshave participated on project cruises. Cores recovered from the cruises and stored in ODPrepositories in the United States and Europe have provided samples to an additional 1,000scientists for longer term post-cruise research investigations. The downhole geochemicaland geophysical logging program, unsurpassed in either academia or industry, is provid-ing remarkable new data with which to study the Earth.

In 1994, NSF and our international partners renewed our commitment to the programfor its final phase. Of the 20 countries that supported ODP initially, only one, Russia, hasbeen unable to continue for financial reasons. As the reputation and scientific impact ofthe program continue to grow internationally, we hope to add additional members and newscientific constituencies. This global scientific participation continues to assure the pro-gram^ scientific excellence by focusing and integrating the combined scientific knowl-edge and capabilities of its member nations.

We wish the program smooth sailing and good drilling!

Neal LaneDirectorNational Science FoundationArlington, Virginia

ForewordBy Joint Oceanographic Institutions, Inc.

This volume presents scientific and engineering results from the Ocean Drilling Pro-gram (ODP). The papers presented here address the scientific and technical goals of theprogram, which include providing a global description of geological and geophysicalstructures including passive and active margins and sediment history, and studying indetail areas of major geophysical activity such as mid-ocean ridges and the associatedhydrothermal circulations.

The Ocean Drilling Program, an international activity, operates a specially equippeddeep-sea drilling ship, the JOIDES Resolution (Sedco/BP 471), which contains state-of-the-art laboratories, equipment, and computers. The ship is 471 feet (144 meters) long, is70 feet (21 meters) wide, and has a displacement of 18,600 short tons. Her derrick towers211 feet (64 meters) above the waterline, and a computer-controlled dynamic-positioningsystem stabilizes the ship over a specific location while drilling in water depths up to27,000 feet (8230 meters). The drilling system collects cores from beneath the seafloorwith 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 theship is devoted to scientific laboratories and equipment. The ship sails with a scientificand technical crew of 51 and a ship's crew (including the drill crew) of 62. The size andice-strengthening of the ship allow drilling in high seas and ice-infested areas as well aspermit a large group of multidisciplinary scientists to interact as part of the scientificparty.

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 holedeeper than 1300 feet (400 meters). For each such hole, there are lowerings of basicoil-industry tools: nuclear, sonic, and electrical. In addition, a Formation MicroScanner isavailable for high-resolution imaging the wall of the hole, a 12-channel logging tool pro-vides accurate velocity and elastic property measurements as well as sonic waveforms forspectral analysis of energy propagation near the wall of the hole, and a vertical seismicprofiler can record reflectors from below the total depth of the hole.

The management of the Ocean Drilling Program involves a partnership of scientistsand governments. International oversight and coordination are provided by the ODPCouncil, a governmental consultative body of the partner countries, which is chaired by arepresentative from the United States National Science Foundation (NSF). The ODPCouncil periodically reviews the general progress of the program and discusses financialplans and other management issues. Overall scientific and management guidance is pro-vided to the operators of the program by representatives from the group of institutionsinvolved in the program, called the Joint Oceanographic Institutions for Deep Earth Sam-pling (JOIDES).

The Executive Committee (EXCOM), made up of the administrative heads of theJOIDES institutions, provides general oversight for ODP. The Planning Committee(PCOM), with its advisory structure, is made up of working scientists and provides scien-tific advice and detailed planning. PCOM has a network of panels and working groups thatscreen drilling proposals, evaluate instrumentation and measurement techniques, andassess geophysical-survey data and other safety and siting information. PCOM uses therecommendations of the panels and committees to select drilling targets, to specify thelocation and major scientific objectives of each two-month drilling segment or leg, and toprovide the science operator with nominations for co-chief scientists.

Joint Oceanographic Institutions, Inc. (JOI), a nonprofit consortium of U.S. oceano-graphic institutions, serves as the National Science Foundation^ prime contractor forODP. JOI is responsible for seeing that the scientific objectives, plans, and recommenda-tions of the JOIDES committees are translated into scientific operations consistent withscientific advice and budgetary constraints. JOI subcontracts the operations of the pro-gram to two universities: Texas A&M University and Lamont-Doherty Earth Observatory

of Columbia University. JOI is also responsible for managing the U.S. contribution toODP under a separate cooperative agreement with NSF.

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 therelevant panels. The science operator also ensures that adequate scientific analyses areperformed on the cores by maintaining the shipboard scientific laboratories and computersand by providing logistical and technical support for shipboard scientific teams. Onshore,TAMU manages scientific activities after each leg, is curator for the cores, distributessamples, and coordinates the editing and publication of scientific results.

Lamont-Doherty Earth Observatory (LDEO) of Columbia University is responsible forthe program's logging operation, including processing the data and providing assistance toscientists for data analysis. The ODP Data Bank, a repository for geophysical data, is alsomanaged by LDEO.

Core samples from ODP and the previous Deep Sea Drilling Project are stored forfuture investigation at four sites: ODP Pacific and Indian Ocean cores at TAMU, DSDPPacific and Indian Ocean cores at the Scripps Institution of Oceanography, ODP andDSDP Atlantic and Antarctic cores through Leg 150 at LDEO, and ODP Atlantic and Ant-arctic cores since Leg 151 at the University of Bremen, Federal Republic of Germany.

Scientific achievements of ODP include new information on early seafloor spreadingand how continents separate and the margins evolve. The oldest Pacific crust has beendrilled and sampled. We have new insights into glacial cycles and the fluctuations ofocean currents throughout geological time. ODP has also provided valuable data that shedlight on fluid pathways through the lithosphere, global climate change both in the Arcticand near the equator, past sea-level change, seafloor mineralization, the complex tectonicevolution of oceanic crust, and the evolution of passive continental margins.

Many of the scientific goals can be met only with new technology; thus the programhas focused on engineering as well as science. To date, ODP engineers have demonstratedthe capability to drill on bare rock at mid-ocean-ridge sites and have developed techniquesfor 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 a closecollaborative effort between ODP engineers and scientists, a system has been developedthat seals selected boreholes ("CORKs") and monitors downhole temperature, pressure,and fluid composition for up to three years. When possible, ODP is also taking advantageof industry techniques such as logging while drilling, to obtain continuous downholeinformation in difficult-to-drill formations.

JOI is pleased to have been able to play a facilitating role in the Ocean Drilling Pro-gram and its cooperative activities, and we are looking forward to many new, excitingresults in the future.

James D. WatkinsAdmiral, U.S. Navy (Retired)PresidentJoint Oceanographic Institutions, Inc.Washington, D.C.

Preface

The Scientific Results volumes of the Proceedings of the Ocean Drilling Program contain spe-cialty papers presenting the results of extensive research in various aspects of scientific ocean drill-ing. The authors of the papers published in this volume have enabled future investigators to gainready access to the results of their research, and I acknowledge their contributions with thanks.

Each paper submitted to a Scientific Results volume undergoes rigorous peer review by at leasttwo specialists in the author's research field. A paper typically goes through at least one revisioncycle before being accepted for publication. We seek to maintain a peer-review system comparableto those of the most highly regarded journals in the geological sciences.

Each Scientific Results volume has an Editorial Review Board that is responsible for obtainingpeer reviews of papers submitted to the volume. This board usually is made up of the two co-chiefscientists for the cruise, the ODP staff scientist for the cruise, and one external specialist who isfamiliar with the geology of the area investigated. In addition, the volume has an ODP staff editorwho assists with manuscripts that require English-language attention and who coordinates volumeassembly.

Scientific Results volumes may also contain short reports of useful data that are not ready forfinal interpretation. Papers of this type, which may be found together in a section in the back of thevolume, are called Data Reports and include no interpretation of results. Data Report papers areread carefully by at least one specialist to make sure they are well organized, comprehensive, anddiscuss the techniques or procedures thoroughly.

To acknowledge the contributions made by this volume's Editorial Review Board, the Boardmembers are designated Editors of the volume and are so listed on the title page. Reviewers ofmanuscripts for this volume, whose efforts are so essential to the success of the publication, arelisted in the front of the book, without attribution to a particular manuscript.

On behalf of the Ocean Drilling Program, I extend sincere appreciation to members of the EditorialReview Boards and to the reviewers for giving their generous contribution of time and effort, whichensures that only papers of high scientific quality are published in the Proceedings.

Paul J. FoxDirectorOcean Drilling ProgramTexas A&M UniversityCollege Station, Texas

REVIEWERS FOR THIS VOLUME

Jan BackmanJack BaldaufJohn A. BarronFranck C. BassinotWilliam BerggrenJens BischofKjell R. Bj0rklundGerhard BohrmannKent BrooksCharlotte A. BrunnerLloyd BurckleJ.P. CauletPavel CepekMario ConiglioAnne de VernalGeorge DixLucy EdwardsJ. FennerCarl Fredrick ForsbergJohan Groot

Rex HarlandDierk HebbelnRüdiger HenrichTimothy D. HerbertEystein JansenMichael A. KaminskiTeresa KingYehoshua KolodnyLeo KristjanssonMarcus G. LangsethSuzanne A.G. LeroyEric LichtfouseAlan R. LordSvein B. ManumErlend MartiniJens MatthiessenLarry MayerD.J. MclntyrePhilip O. MeyersAlan Mix

David W. MurrayG. NorrisDelia W. OppoD.J.W. PiperA. James PowellWilliam F. RuddimanJoar SaettemKatharina von SalisDetmar SchnitkerHans Peter SejrupWilliam J. ShowersH. SigurdssonAnders SolheimDorrick A.V. StowPatrick T. TaylorTorgny VinjeTore O. VorrenP.P.E. Weaver

OCEAN DRILLING PROGRAM

MEMBER ORGANIZATIONS OF THE JOINTOCEANOGRAPHIC INSTITUTIONS FORDEEP EARTH SAMPLING (JOIDES)

University of California at San Diego, Scripps Institutionof Oceanography

Columbia University, Lamont-Doherty Earth Observatory

University of Hawaii, School of Ocean and Earth Scienceand Technology

University of Miami, Rosenstiel School of Marine andAtmospheric Science

Oregon State University, College of Oceanic andAtmospheric Sciences

University of Rhode Island, Graduate School ofOceanography

Texas A&M University, College of Geosciences andMaritime Studies

University of Texas at Austin, Institute for Geophysics

University of Washington, College of Ocean and FisherySciences

Woods Hole Oceanographic Institution

Canada/Australia Consortium for the Ocean DrillingProgram, Department of Energy, Mines and Resources(Canada) and Department of Primary Industries andEnergy (Australia)

European Science Foundation Consortium for OceanDrilling (Belgium, Denmark, Finland, Greece, Iceland,Italy, The Netherlands, Norway, Spain, Sweden,Switzerland, and Turkey)

Federal Republic of Germany, Bundesanstalt fürGeowissenschaften und Rohstoffe

France, Institut Français de Recherche pour 1'Exploitationde la Mer

Japan, University of Tokyo, Ocean Research Institute

United Kingdom, Natural Environment Research Council

PRIME CONTRACTOR

Joint Oceanographic Institutions, Inc.Washington, D.C.

David A. FalveyDirector, Ocean Drilling Programs

OPERATING INSTITUTION

College of Geosciences and Maritime StudiesTexas A&M UniversityCollege Station, Texas

Robert A. DuceDean

OCEAN DRILLING PROGRAM

Paul J. FoxDirector

Timothy J.G. FrancisDeputy Director

Richard G. McPhersonAdministrator

Jack G. Baldauf, ManagerScience Operations

Brian Jonasson, ManagerDrilling Services

Ann Klaus, ManagerPublications

Russell B. Merrill, Curator and ManagerInformation Services

Robert E. Olivas, ManagerTechnical and Logistics Support

LOGGING OPERATOR

Borehole Research GroupLamont-Doherty Earth ObservatoryColumbia UniversityPalisades, New York

David Goldberg, Head

PARTICIPANTS ABOARD THE JOIDES RESOLUTION FOR LEG 151

Jörn ThiedeCo-Chief Scientist

GEOMARResearch Center for Marine GeosciencesWischhofstraße 1-3, Building 4D-24148 Kiel 14Federal Republic of Germany

Annik M. MyhreCo-Chief Scientist

Department of GeologyUniversity of OsloPB 1047, BlindemN-0316 Oslo 3Norway

John V. FirthODP Staff Scientist

Ocean Drilling ProgramTexas A&M University Research Park1000 Discovery DriveCollege Station, Texas 77845-9547U.S.A.

Naokazu AhagonSedimentologist

Marine Geology and GeophysicsOcean Research InstituteUniversity of Tokyo1-15-1 Minamidai, Nakano-kuTokyo 164Japan

Kevin S. BlackPhysical Properties Specialist

School of Ocean SciencesUniversity of Wales (Bangor)Menai BridgeAnglesey Gwynedd LL59 5HNUnited Kingdom

Jan BloemendalStratigraphic Coordinator

Department of GeologyUniversity of LiverpoolP.O. Box 147Liverpool L69 3BXUnited Kingdom

Garrett W. BrassInorganic Geochemist

Division of Marine Geology and GeophysicsRosenstiel School of Marine and Atmospheric ScienceUniversity of Miami4600 Rickenbacker CausewayMiami, Florida 33149-1098U.S.A.

James F. BristowLDEO Logging Scientist

Borehole ResearchDepartment of GeologyUniversity of LeicesterLeicester LEI 7RHUnited Kingdom

Nancy ChowSedimentologist

Department of Geological SciencesUniversity of ManitobaWinnipeg, Manitoba R3T2N2Canada

Michel CremerSedimentologist

Département de Géologie et OcéanographieURA CNRS 197Université de Bordeaux IAvenue des Facultés33405 Talence CedexFrance

Linda DavisIgneous Petrologist

Department of Geological SciencesUniversity of Texas at AustinP.O. Box 7909Austin, Texas 78712-7909U.S.A.

Benjamin FlowerSedimentologist

Department of Geological SciencesUniversity of California, Santa BarbaraSanta Barbara, California 93106U.S.A.

Torben FronvalSedimentologist

Geologisk InstituttUniversitetet i BergenAllégaten 41N-5007 BergenNorway

Julie HoodPhysical Properties Specialist

Division of Marine Geology and GeophysicsRosenstiel School of Marine and Atmospheric ScienceUniversity of Miami4600 Rickenbacker CausewayMiami, Florida 33149-1098U.S.A.

Donna HullPaleontologist (radiolarians)

Programs in GeosciencesUniversity of Texas, DallasP.O. Box 830688Richardson, Texas 75083-0688U.S.A.

Nalàn KoçPaleontologist (diatoms)

Geologisk InstituttUniversitetet i BergenAllégaten 41N-5007 BergenNorway

* Addresses at time of cruise.

Birger LarsenPhysical Properties Specialist

Danmarks Geologiske UndersΦgelseThoravej 8DK-2400 Copenhagen NVDenmark

Mitchell W. LyleJOIDES Logging Scientist

CGISSDepartment of GeosciencesBoise State UniversityBoise, Idaho 83725U.S.A.

Jerry McManusSedimentologist

Division of Oceans and ClimateLamont-Doherty Earth ObservatoryColumbia UniversityPalisades, New York 10964U.S.A.

Suzanne O'ConnellSedimentologist

Department of Earth and Environmental SciencesWesleyan UniversityMiddletown, Connecticut 06459-6034U.S.A.

Lisa Ellen OstermanPaleontologist (benthic foraminifers)

Department of PaleobiologyNHB E207Smithsonian InstitutionWashington, DC 20560U.S.A.

Frank R. RackPhysical Properties Specialist

Ocean Mapping GroupDepartment of Surveying EngineeringUniversity of New BrunswickP.O. Box 4400Fredericton, New Brunswick E3B 5A3Canada

Tokiyuki SatoPaleontologist (nannofossils)

Institute of Applied Earth SciencesMining CollegeAkita UniversityTegata-Gakuencho 1-1Akita 010Japan

Reed P. SchererPaleontologist (diatoms)

Byrd Polar Research CenterOhio State University1090 Carmack RoadColumbus, Ohio 43210-1002U.S.A.

Dorothee SpieglerPaleontologist (planktonic foraminifers, Bolboforma)

GEOMARResearch Center for Marine GeosciencesWischhofstraße 1-3, Building 4D-24148 Kiel 14Federal Republic of Germany

Rüdiger SteinOrganic Geochemist

Alfred-Wegener-Institute for Polar and Marine ResearchColumbusstraße 2D-27568 BremerhavenFederal Republic of Germany

David WilliamsonPaleomagnetist

Laboratoire de Géologie du QuaternaireCNRS, Case 907Faculté des Sciences de Luminy13288 Marseille Cedex 9France

Bill WittePaleomagnetist

Geophysical InstituteUniversity of AlaskaFairbanks, Alaska 99775U.S.A.

Thomas Wolf-WellingSedimentologist

GEOMARResearch Center for Marine GeosciencesWischhofstraße 1-3, Building 4D-24148 Kiel 14Federal Republic of Germany

PARTICIPANTS ABOARD ICE-SUPPORTVESSEL FENNICA

Mark TadrossSea-Ice Physicist

Scott Polar Research InstituteUniversity of CambridgeLensfield RoadCambridge CB2 1ERUnited Kingdom

Stephen WellsSea-Ice Physicist

Scott Polar Research InstituteUniversity of CambridgeLensfield RoadCambridge CB2 1ERUnited Kingdom

SEDCO OFFICIALS

Captain Edwin G. OonkMaster of the Drilling Vessel

Overseas Drilling Ltd.707 Texas Avenue South, Suite 213DCollege Station, Texas 77840-1917U.S.A.

Kenneth D. HomeDrilling Superintendent

Overseas Drilling Ltd.707 Texas Avenue South, Suite 213DCollege Station, Texas 77840-1917USA.

ODP ENGINEERING AND OPERATIONS PERSONNEL

Gene Pollard Operations Superintendent

ODP TECHNICAL AND LOGISTICS PERSONNEL

Wendy J. AutioTimothy BronkBrenda Jo ClaesgensBradley CookCesar FloresDennis K. GrahamMargaret HastedtKazushi ("Kuro") KurokiJaquelyn K. LedbetterJon S. LloydErinn McCartyMatt MefferdWilliam G. MillsDwight E. MossmanAnne PimmelWilliam StevensMark Watson

Marine Laboratory Specialist/X-ray, PaleontologyMarine Laboratory Specialist/Storekeeper, Thin SectionMarine Laboratory Specialist/YeopersonMarine Laboratory Specialist/PhotographyMarine Computer Specialist/System ManagerMarine Laboratory Specialist/ChemistryMarine Laboratory Specialist/MagneticsAssistant Laboratory Officer, X-ray, UnderwayMarine Laboratory Specialist/Downhole MeasurementsMarine Laboratory Specialist/Physical PropertiesMarine Laboratory Specialist/Curatorial RepresentativeMarine Computer Specialist/System ManagerLaboratory OfficerMarine Laboratory Specialist/Underway, FantailMarine Laboratory Specialist/ChemistryMarine Electronics SpecialistMarine Electronics Specialist

Ocean Drilling Program Publications Staff*

Publications ManagerAnn Klaus

Editorial Supervisor/Publications SpecialistM. Kathleen Phillips

Senior EditorJennifer A. Marin

EditorsGeorgia L. FoxAngeline T. MillerChristine M. MillerRuth N. Riegel

Chief Production EditorJennifer Pattison Hall

Production EditorsKaren O. BensonJaime A. GraciaWilliam J. Moran (this volume)

Senior Publications CoordinatorGudelia ("Gigi") Delgado

Publications CoordinatorRose Pandolph Sauser

Copier/Distribution SpecialistAnn Yeager

Senior PhotographerJohn W. Beck

PhotographerBradley James Cook

Chief IllustratorDeborah L. Partain

IllustratorsMelany R. BorsackL. Michelle BriggsKatherine C. IrwinNancy H. Luedke

Prime Data CoordinatorKaterina Petronotis

Production AssistantsMarianne GoreckiMary Elizabeth Mitchell

Student AssistantsMaria Barbéy, Beverly Cooper, Theresa Elam, Amy Nevergold, Weyland M.A. Simmons

* At time of publication.

PUBLISHERS NOTES

Current policy requires that all figures published in Scientific Results volumes of the Proceedings of the Ocean Drilling Program beprovided by the authors.

Abbreviations for names of organizations and publications in ODP reference lists follow the style given in Chemical AbstractsService Source Index (published by American Chemical Society).

TABLE OF CONTENTS

VOLUME 151—SCIENTIFIC RESULTS

SECTION 1: INTRODUCTION

1. Introduction to the North Atlantic-Arctic Gateways: plate tectonic-paleoceanographic historyand significance 3J. Thiede and A.M. Myhre

2. Statistical study of sea-ice variability at the planned locations of Leg 151 drilling sites 25P. Wadhams and M.P. Casarini

SECTION 2: BIOSTRATIGRAPHY

3. Pliocene to Quaternary calcareous nannofossil biostratigraphy of the Arctic Ocean,with reference to late Pliocene glaciation 39T. Sato and K. Kameo

4. Neogene diatom biostratigraphy of the Iceland Sea Site 907 61N. Koç and R.P. Scherer

5. Late Paleogene diatom biostratigraphy and paleoenvironments of the northern Norwegian-Greenland Sea 75R.P. Scherer and N. Koç

6. Cenozoic siliceous flagellates from the Fram Strait and the East Greenland Margin:biostratigraphic and paleoceanographic results 101S. Locker

7. Paleoceanography and biostratigraphy of Paleogene radiolarians from the Norwegian-Greenland Sea 125D.M. Hull

8. Planktonic foraminifer Cenozoic biostratigraphy of the Arctic Ocean, Fram Strait(Sites 908-909), Yermak Plateau (Sites 910-912 ), and East Greenland Margin (Site 913) 153D. Spiegler

9. Agglutinated benthic foraminiferal biostratigraphy of Sites 909 and 913, northernNorth Atlantic 169L.E. Osterman and D. Spiegler

10. Pliocene and Quaternary benthic foraminifers from Site 910, Yermak Plateau 187L.E. Osterman

11. Ostracoda from Sites 910 and 911 197T.M. Cronin and R. Whatley

12. Upper middle Eocene to Oligocene dinoflagellate biostratigraphy and assemblage variationsin Hole 913B, Greenland Sea 203J.V. Firth

13. Dinoflagellate cyst ecostratigraphy of Pliocene-Pleistocene sediments from the Yermak Plateau(Arctic Ocean, Hole 911A) 243J. Matthiessen and W. Brenner

14. Tertiary dinoflagellate biostratigraphy of Sites 907, 908, and 909 in the Norwegian-Greenland Sea 255N.E. Poulsen, S.B. Manum, G.L. Williams and M. Ellegaard

15. Oligocene and Miocene vegetation in high latitudes of the North Atlantic: palynological evidencefrom the Hovgárd Ridge in the Greenland Sea (Site 908) 289M.C. Boulter and S.B. Manum

16. Pliocene-Pleistocene pollen assemblages from the Yermak Plateau, Arctic Ocean: Sites 910and 911 297D.A. Willard

SECTION 3: IGNEOUS PETROLOGY/GEOCHEMISTRY

17. Geochemistry and origin of Pliocene and Pleistocene ash layers from the Iceland Plateau,Site 907 309C. Lacasse, M. Paterne, R. Werner, H.-J. Wallrabe-Adams, H. Sigurdsson, S. Carey, and G. Pinte

18. Distribution, chemical composition, and sources of Oligocene to Miocene volcanic ashes fromSites 907, 908, and 913 333R. Werner, H.-J. Wallrabe-Adams, C. Lacasse, H.-U. Schmincke, and J. Thiede

19. The petrology and 40Ar/39Ar age of tholeiitic basalt recovered from Hole 907A, IcelandPlateau 351L.L. Davis and W.C. Mclntosh

SECTION 4: PHYSICAL PROPERTIES AND GEOTECHNICAL STUDIES

20. Comparison of natural gamma ray activity profiles from downhole logging and theMST core logger at Site 911 (Yermak Plateau) 369M. Lyle, J. Bristow, J. Bloemendal, and F.R. Rack

21. Analysis and interpretation of X-ray images of sediment cores from Hole 910D, YermakPlateau: preliminary results 377F.R. Rack, R. Finndin, and K. Moran

SECTION 5: SEDIMENTOLOGY/GEOCHEMISTRY

22. Organic carbon and n-alkane distribution in late Cenozoic sediments of Arctic GatewaysSites 909 and 911 and their paleoenvironmental implications: preliminary results 391R. Stein and R. Stax

23. Hydrocarbons as indicators for provenance and thermal history of organic matter in lateCenozoic sediments from Hole 909C, Fram Strait 407J. Rinna, J. Rullkötter, and R. Stein

24. Origin of authigenic carbonates in Eocene to Quaternary sediments from the Arctic Ocean andNorwegian-Greenland Sea 415N. Chow, S. Morad, and I.S. Al-Aasm

SECTION 6: PALEOCEANOGRAPHY

25. Variability in sea-surface conditions in the North Atlantic-Arctic Gateways during the last140,000 years 437J.F. McManus, CO. Major, B.P. Flower, and T. Fronval

26. Late Quaternary stable isotopic stratigraphy of Hole 910A, Yermak Plateau, Arctic Ocean:relations with Svalbard/Barents Sea ice sheet history 445B.P. Flower

27. Late Neogene paleoclimates and paleoceanography in the Iceland-Norwegian Sea: evidencefrom the Iceland and V0ring Plateaus 455T. Fronval and E. Jansen

28. Quaternary paleoceanography and paleoclimatology of the Fram Strait/Yermak Plateau region:evidence from Sites 909 and 912 469K. Hevr0y, G. Lavik, and E. Jansen

29. Recent to middle Miocene diatom productivity at Site 907, Iceland Plateau 483B. StabellandN. Koç

30. Variations in surface water mass conditions in the Norwegian-Greenland Sea: evidence fromPliocene/Pleistocene calcareous plankton records (Sites 644, 907, 909) 493K.-H. Baumann, H. Meggers, and R. Henrich

31. Cenozoic Arctic Gateway paleoclimate variability: indications from changes incoarse-fraction composition 515T.C.W. Wolf-Welling, M. Cremer, S. O'Connell, A. Winkler, and J. Thiede

32. Neogene paleoceanography and paleoclimate history from Fram Strait: changesin accumulation rates 569S. 0'Connell, T.C.W. Wolf-Welling, M. Cremer, and R. Stein

33. Stable isotopic composition (δ 1 8 O c o 2-, δ13C) of early Eocene fish-apatite from Hole 913B:an indicator of the early Norwegian-Greenland Sea paleosalinity 583F.P. Andreasson, B. Schmitz, and D. Spiegler

SECTION 7: SYNTHESES

34. Development of physical properties relationships, interhole composite depth profiles,and sedimentologic ground truthing of multi-sensor core measurements: a synthesis of results .. .595F.R. Rack, J. Bloemendal, T.C.W. Wolf-Welling, S. 0'Connell, M. Cremer, A. Winkler, J. Thiede,K. Black, and J. Hood

35. Biostratigraphic synthesis of Leg 151, North Atlantic-Arctic Gateways 627D.M. Hull, L.E. Osterman, and J. Thiede

36. The paleoceanographic history of the North Atlantic-Arctic Gateways: synthesis of the Leg 151drilling results 645J. Thiede and A.M. Myhre

S E C T I O N 8: I N D E X

Index 659

(For JOIDES Advisory Groups and ODP Sample and Data Distribution Policy, please see ODP Proceedings,Scientific Results, Volume 148, pp. 491-500.)

CD-ROM Materials (in back pocket)The CD-ROM in the back pocket of this volume contains an electronic version of the Leg 151 Scientific Results

volume in Adobe Acrobat. Also on the CD-ROM are the following tables not contained in the printed book:Chapter 32:

Table 3. Site 908: bulk accumulation rate, linear sedimentation rate, %CaCO3, %TOC, and %sand.Table 4. Site 909: bulk accumulation rate, linear sedimentation rate, %CaCO3, %TOC, and %sand.