The morning agenda was full with greetings, annual evaluations for some of the ASPP personnel, crossover, and the introduction of the new director of Science Services, Tom Davies. This gathering was followed by individual introductions.
A seminar was conducted by George Claypool, a Leg 174A participant and Safety Panel member, for the chemists, Operations Managers, and Staff Scientist. George explained some of the background and nomenclature used to interpret and report typical biologic and petro gas analysis.
Freight and cores were moved off and on the ship the second day. Rainy weather deterred progress
on some of the planned tasks. The remaining days in port permitted the closure of ship-related
Underway from Halifax
The JOIDES Resolution sailed on 20 June at 1800 after five days in port. Navigation tapes were initiated upon leaving the dock and watches started the following day, monitoring the 12- and 3.5-kHz depth recorders. The magnetometer sensor was not deployed because of traffic, shallow water on the banks, and knowledge that it is a well-surveyed area. Differential global positioning system (dGPS) navigation service was arranged from OmniStar Houston for the drilling area selected. Differential GPS indicators on the instruments strengthened on both of the Omnistar receivers as the ship progressed south. Clocks were retarded 1 hr from Atlantic Standard time to East Coast Standard Time at 2400 on the 21st. The two-day passage to the drill site off New Jersey was smooth. Once on site, the WinFrog navigation displays showed position scatter leading to the realization that dGPS did not engage automatically as anticipated. By the following day, the procedure to use the differential correction was in place and site fixes were falling in a 10-14 m circle.
Sites 1071 and 1072
The drilling sites selected off the New Jersey coast complemented the set of sites drilled on Leg 150 on the continental slope, continuing the investigation of the records of the changing of sea level on a passive margin. The sites were in very shallow water and this placed tight restraints on the dynamic positioning capabilities of the ship.
The subsea camera was deployed at each site to document the seafloor being drilled and to verify
that no debris or cables were present.
The anticipated gassy cores and high recovery were stymied when thick layers of unconsolidated sand and gravel were encountered. Numerous attempts were made to drill through these unconsolidated layers to deeper reflectors and objectives. Mechanical failures in the top drive consumed nearly a week of the operation time available. Several holes were wireline logged, one VSP was generated using Schlumberger triggering and tools, and a GI Gun sound source and two LWD dedicated holes were completed.
Site 1073 (MAT 13B)
After getting the LWD tool stuck for several hours, the decision was made to move to an alternate deeper site, Site 1073. APC coring proceeded in 640 m of water, 22 km from the other two sites. Gassy and expanding cores were recovered to a depth of 660 m. Adara temperature tool heat-flow measurements generated a gradient for the area; TENSOR tool orientation data complemented the cryogenic magnetometer measurements. Wireline logs were collected; a VSP experiment was completed in two segments.
The site was terminated about 1730 on 18 July for the transit to New York City. Only navigation
data was collected on the 8-hr approach.
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