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microfossils at these latitudes. JOIDES therefore asked DSDP to change plans, substituting an east-west transect along the equator for the southern part of the original track. This was an early demonstration of the need to keep feeding new results into future planning and established an enduring modus operandi.

The results from these three early Pacific legs documented the strong dependence on latitude not only of pelagic sediment accumulation rates, but also of the depth profiles of carbonate dissolution for the past 35 million years. The drilling further opened up the problem of sedimentation on an oceanic plate that is moving not only east-west, as in the Atlantic, but also north-south, across the equatorial high-fertility zone. From the sediment-thickness data, epoch by epoch, a quantitative estimate of the rate of northward plate motion could be made and compared with independent estimates coming from the recently introduced fixed-hotspot model for the evolution of the linear Hawaiian volcanic chain. Recognition of the abundance of well-preserved microfossils and of the near-continuous record of sedimentation in the Pacific equatorial zone led to several later coring legs that provided us with the material basis for an extraordinarily detailed biostratigraphic time scale, combining all three major groups of planktonic microfossils: foraminifera, coccolithophorids (nanofossils), and radiolarians.

The results from the two-leg swing into the central and western Pacific, the region farthest from the actively spreading East Pacific Rise, could only hint at the history of the Mesozoic Pacific. On one of the legs, the ship was used more like a dredge than a drill and few cores were recovered during repeated attempts (36 holes!) to core the sediment-basement contact. Two western Pacific oceanic plateaus, Shatsky and Ontong Java, were drilled, and Lower Cretaceous strata were confirmed on Shatsky. Ontong Java (still the cynosure of many eyes) is covered by about 1 km of pelagic sediments, but chert layers, here as elsewhere, blocked penetration of the flat-faced diamond bits used in the early days of the project and interfered with recovery of more than a few chips of rock. Better technology was urgently needed.

Lessons Learned Early

A lesson learned from drilling during the first 18 months from both engineering and scientific perspectives was that coring should be continuous, and that vastly improved methods were required to get these continuous records in piles of sediment with widely varying physical properties (e.g., alternating chert and chalk layers). The JOIDES Planning Committee later ordained continuous coring as the norm and engineers developed better drill bits, a system of heave compensation to keep the drill bit from moving up and down with the motion of the vessel (ready for sea trials on Leg 33 in 1973), and a hydraulic piston corer that recovers long, undisturbed cores free of vessel motion (ready for Leg 64 in 1978). Pressure core barrels have been deployed to retrieve gas hydrate samples under in situ pressures.

Gradually and intermittently, then more regularly, down-hole logging was instituted for most holes, and a fruitful collaboration was established with logging companies, to improve and widen the scope and effectiveness of the logging tools available. These tools have not only helped to fill in gaps in the cores, but enabled correlation of drill results with those of seismic reflection profiling, and establishment of heat flow values and other geophysical parameters.

From the very beginning, scientific panels advocated using the holes as ''natural laboratories," but budgets and time constraints kept this activity at a slow pace. Nonetheless, over the years, the drilled holes have been increasingly used for measurement of such variables as heat flow and for experiments on fluid flow, seismic velocity, and earthquake monitoring, to name but a few.

What was needed, from the very first, was money to design, test, and put into action these technologic innovations. The reality was that there was never enough money. The contract with Global Marine was fixed and the remaining funds were for all the rest. If the planners asked for better bits or more logging, then the money had to come out of science operations. For example, until the very end of DSDP in 1983, NSF allowed expenditure for only one computer for word processing for a project that was publishing a 1000-page hard-back report on scientific results every two months.

The Long Haul

As easily predicted, before the ship had progressed more than part way along its planned nine-leg track, plans were already changing and new proposals were submitted to extend the project. So excited was the scientific community by the early results that NSF, after suitable review and by simple amendment to the initial contract, extended the project for another two years. Time and again extensions were granted, going on now for 30 years. Contractors have changed, the JOIDES organization has expanded, international partners have been recruited, funding sources have been added (and deleted), names have changed, the drill ship has been replaced and project management shifted, while the drilling goes on and new scientific results pour in.

Almost immediately after the formation of JOIDES, the University of Washington was added to the group and U.S. JOIDES institutions now number eleven. A U.S. corporate entity, Joint Oceanographic Institutions, Inc., was created to provide fiscal responsibility for JOIDES, so that NSF could sign contracts to support JOIDES activities. From the beginning of DSDP, many non-U.S. scientists had been members of the scientific parties aboard the ship, but in 1975, by requests from several countries and with the active encouragement of NSF, the project was formally internationalized as the International Program for Ocean Drilling (IPOD). Several partner nations (Germany, the USSR, France, United



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