162 Preliminary Report

Site 983

Site 983 (GARDAR-1) was a high-priority contingency site which was drilled because the leg was ahead of schedule by nearly 2 days. The operational plan called for three piston-cored holes to approximately 300 m below the sea bed. Because time was short, we decided to core three shallower holes rather than two deeper holes.

Head winds limited the vessel's speed while en route to Site 983. Prior to slowing down for presite seismic profiling, the vessel averaged a mere 8.3 kt. At 0742 hr on 21 July 1995 the ship slowed down to 6.0 kt, and the seismic gear was deployed for a limited pre-site survey of the site. By 1158 hr on 21 July the seismic profiling gear was recovered, the vessel returned to the drilling location, based on GPS coordinates, and the positioning beacon was deployed, initiating Hole 983A.

A standard APC/XCB BHA was used for all holes at Site 983, including a nonmagnetic drill collar. Subsequent holes (983B and C) were offset 15 m to the north. The mudline was established for each hole. The APC firing depth was offset by a few meters for subsequent holes in order to establish continuous sediment sections.

Coring proceeded without incident at all three holes until scientific target depth was reached. The following cores were oriented with the Tensor tool: 983A-3H through 27H; 983B-3H through 27H; and 983C-3H though 27H. The drill pipe was tripped above mudline, clearing the seafloor, and the positioning beacon was released and subsequently recovered at 2225 hr on 23 July 95. The vessel was secured for transit and we were underway at 0200 hr on 24 July 95.

To Operations Site 984

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