Logging Operations in Hole 1082A
In preparation for logging, an aluminum go-devil was dropped to ensure the opening of the lockable float valve, and the hole was flushed with a high-viscosity mud treatment. The drill string was then pulled up, and the bit was placed at the logging depth of 94.1 mbsf. Hole 1082A was logged with a full suite of sensors. For each run, the pipe was set at 94.1 mbsf and pulled back to 65.0 mbsf during logging. Logging operations began at 0200 hr on 15 September. The first log was conducted with the seismic-stratigraphic suite (25.8 m long). This suite was made up of the NGT, LSS, DITE-SFR, and TLT sondes. This tool string was deployed in the pipe at 0255 hr and logged the hole up from 599.3 mbsf. The tool was recovered at 0700 hr. The second log was made with the lithoporosity suite (19.5 m long) and included the HNGS, APS, LDS, and TLT sondes. The tool was deployed at 0800 hr and logged the hole up from bottom at 599.3 mbsf. The tool was pulled out of the pipe at 1225 hr. The third logging run was made with the FMS suite (12.10 m long) and included the NGT, GPIT, and FMS sondes. This tool was deployed at 1325 hr and logged the hole from 599.3 mbsf. The tool was recovered at 1700 hr. The fourth and last log was with the magnetic susceptibility suite (11.8 m long) and included the NGT, SUMT, and NRMT sondes. The tool was deployed in the pipe at 1730 hr and logged the hole from 599.3 mbsf. It was retrieved at 2010 hr. The logging equipment was rigged down by 2100 hr, and the hole was filled with heavy mud. The drill string was then pulled out of the hole, with the bit clearing the seafloor at 0005 hr on 16 September.
The vessel was offset 30 m to the south, and Hole 1082B was spudded with the APC at 0110 hr on 16 September. The recovery of the first core established the seafloor depth at 1291.8 mbrf. APC coring advanced without incident to refusal at 127.0 mbsf with 104.9% recovery. Cores were oriented starting with 4H. The bit cleared the seafloor at 0855 hr on 16 September, thereby ending operations at Hole 1082B.
Hole 1082C was spudded with the APC at 0855 hr on 16 September. The recovery of the first core established the seafloor depth at 1293.5 m. APC coring advanced to 202.0 mbsf with 107.8% recovery. The last two cores (Cores 175-1082C-23H and 24H) were partial strokes. Cores were oriented starting with 3H. The drill string was then retrieved, with the bit clearing the seafloor at 2315 hr. The beacon was recovered, and the hydrophones and thrusters were retracted. At 0200 hr on 17 September, the vessel was under way to Site 1083.
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