Glomar Challenger Deep Sea Drilling Vessel

This ship, which brings together marine and petroleum technologies, and which carries systems designed for the locomotive and aerospace industries, has cored the ocean floor in waters over 19,000 feet deep. This is largely possible because she is able to hold a fixed position steadily, and, maintaining that position, orient herself throughout the compass azimuths.

Introduction

The combined thinking of petroleum and marine talent has brought about a significant progression in the evolution of offshore drilling a floating base of the single hull form, self-propelled, completely self-sufficient, able to remain fixed on station without anchoring, while safely supporting a deep drilling operation over extensive periods, almost anywhere in the world ocean.

For years engineers and drillers in the offshore industry have known that deep water drilling with dynamic positioning could and should be done. Scientists have theorized that it was eminently possible; and there have been operations by a few small coring vessels, and other experimental operations, that at least in part have proven it could be done. Several times in recent years it seemed that the petroleum industry, by itself, would sponsor this development, but the time was not right, certain technological breakthroughs were not proven, and the economic risks were not justified.

In 1964, a deep sea drilling proposal sponsored by several universities was started by JOIDES (Joint Oceanographis Institutions Deep Earth Survey). Participating were Scripps Institution of Oceanography, Participating were Scripps Institution of Oceanography, Woods Hole Oceanographic Institute, Lamont Oceanographic Laboratory of Columbia U., and Miami U.'s Institute of Marine Science. This program envisioned retrieving sediment cores in 12,000 to 18,000 ft of water. Its planning led to the current Deep Sea Drilling Project (DSDP), funded by the National Science Foundation and involving the same institutions. Scripps Institution has been designated as the manager for the DSDP.

As the result of an award by Scripps Institution, and to meet the exacting requirements of the 18-month deep-ocean coring program, Glomar Challenger was designed and built by Global Marine Inc.

At the time this paper was written there had been but a few weeks of actual experience in deep water drilling by this ship. In the interim period between Sept., 1968, and Sept., 1969, period between Sept., 1968, and Sept., 1969, the Glomar Challenger has successfully drilled and cored approximately 70 deep-water core holes. The deepest record for water depth is 19,654 ft, with a penetration of 433 ft, making a total drillpipe length of 20,087 ft. The acoustic position sensing system has been reliable and the acoustic signal strong and steady even in such water depth. The average accuracy of the ship's positioning system has been to less than 100-ft radius excursions at the surface. Thus far the technical and scientific knowledge gained by this project has met or exceeded the expectations of the National Science Foundation, Scripps Institution of Oceanography, and Global Marine.

JPT

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