Ocean Drilling Program: Recent Highlights and Future Expeditions

Rabinowitz, Philip D. (Ocean Drilling Program, Texas A&M U.)

OnePetro 

Summary

During the past year, exploration of the deep ocean floor through scientificocean drilling has yielded important results with respect to evolution of oceancrust and continental margins and paleoceanography. This paper describes theOcean Drilling Program's (ODP's) scientific and technical achievements duringits ninth year of field operations and discusses areas of future study.

Introduction

The ODP, an international basic research program of scientific oceandrilling, is the successor to the Deep Sea Drilling Project (DSDP). TexasA&M U. (TAMU), College Station, TX, is the science operator. ODP is fundedby the U.S. Natl. Science Foundation with major contributions from 18 othercountries. This international partnership is called the Joint OceanographicInstns. for Deep Earth Sampling (JOIDES). To date, JOIDES Resolution (Fig. 1),ODP's scientific drillship, has retrieved sediment and hard rock samples frombeneath the deep-sea floor at 308 sites (Table 1) in search of answers toimportant scientific problems designated by JOIDES. These sites in theAtlantic, eastern and western Pacific, and Indian oceans include high-latitudezones bordering east and west Antarctica, Baffin Bay, and the Mediterranean,Caribbean, Norwegian, Sulu, Celebes, Philip pine, Japan, and Coral seas. Thusfar, 1,315 scientists from around the world have brought more than 510,000individual core samples from ODP cruises to their respective institutions forfurther study. JOIDES member countries include the U.S., France, Japan, theU.K., Canada, Australia, Germany, and members of the European ScienceFoundation: Belgium, Denmark, Finland, Iceland, Italy, Greece, The Netherlands,Norway, Spain, Sweden, Switzerland, and Turkey.

JOIDES Resolution contains a seven-story, 1115 m2 laboratory stack with thestate-of-the-art equipment necessary to ana lyze the physical and chemicalproperties of the collected rocks. The 50-member scientific and technical team,which remains aboard the vessel for expeditions that last about 2 months, hasthe following types of laboratories available for research: sedimentology,physical properties, paleomagnetic, chemistry, paleontology, petrology,thin-section, X-ray diffraction, X-ray fluorescence, and downhole measurement.In addition, photographic, electronics, and refrigerated-core storagefacilities are available. During approach or departure from drillsites, theship's geophysics laboratory records and processes digital single-channelseismics. JOIDES Resolution is also equipped with a research-oriented computersystem designed to perform routine chemical, arithmetic, and graphics tasks.Two mainframe computers serve as a cen tral processor and data library for 50microcomputers distributed throughout the laboratories.

Table 2 shows main characteristics of the dynamically positioned JOIDESResolution.

Scientific Services

TAMU provides services for curation and distribution of cored material andassociated databases and the production of ODP publications.

A series of formal and informal published scientific reports is issuedduring the period shortly before each cruise through approximately 3 yearsafter the cruise. Our principal formal publication, Proceedings of the OceanDrilling Program, is divided into two parts: Initial Reports, which containdescriptions of drilling sites, including core photographs, and is distributed12 to 15 months after the cruise; and Scientific Results, which containspeerreviewed specialty papers and is distributed 36 months after thecruise.

Three core repositories are managed by TAMU/ODP: one at Scripps Instn. ofOceanography, U. of California, San Diego, CA, houses the Indian and PacificOcean cores collected by the predecessor program, DSDP; one at Lamont-DohertyGeological Observatory of Columbia U., New York City, houses the DSDP and ODPAtlantic Ocean cores; and one at TAMU houses the ODP-collected Indian andPacific Ocean cores. These repositories contain more than 160 km of corecollected since 1968 by DSDP and ODP. A fourth core repository, to open inearly 1994 in Bremen, Germany, will house future Atlantic Ocean cores.Scientists throughout the world may request samples from the ODP curator atTAMU, who maintains records of all proposed investigations to study the DSDPand ODP samples.

Data generated from cores together with geophysical data are entered into acomputerized database consisting of several data files (i.e., geochemistry andphysical properties). The database can be searched using almost any specifiedcriteria contained in the data files. Searches that cross-reference severaldata-file documents are available to the scientific community.

Scientific and Technical

Objectives and Operations

During the first 9 years of ODP, we ad dressed many of the scientific andtechni cal objectives defined at two conferences on scientific ocean drilling(Conferences on Scientific Ocean Drilling [COSOD's] 1 and 2). The scientificobjectives defined at COSOD II include investigating changes in the globalenvironment, mantle/crust inter actions, fluid circulation in the crust, theglobal geochemical budget, stress and deformation of the lithosphere, andevolutionary processes in oceanic communities. In addition, new technologiesnecessary to implement these scientific investigations, such ashigh-temperature drilling, drilling and coring in difficult formations(fractured basalts, unconsolidated sands, chert, etc.), and downholemeasurements, were addressed.

Previous reports summarized the scientific objectives for Legs 100 through146. Below we summarize results from the informal preliminary reports publishedat ODP for Cruises 147 through 152, completed during our ninth year of fieldoperations, and describe future cruises in the Atlantic Ocean. Fig. 2 givesgeneralized ODP site locations.

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