Site 1125
Hole 1125A
The 198-nmi voyage to Site 1125 (proposed site SWPAC-3A) was accomplished at an average speed of 9.0 kt. The vessel proceeded directly to the GPS coordinates of the location. The hydrophones and thrusters were lowered and the APC/XCB BHA was assembled using a 9 7/8" PDC bit and deployed. Hole 1125A was spudded with the APC at 0352 hr on 3 October. The recovery indicated a water depth of 1364.6 mbsl. APC coring advanced without incident to refusal, which was at 203.5 mbsf when Core 181-1125A-22H failed to achieve full stroke. The Adara heat-flow shoe was deployed at 42.5 mbsf (5H), 61.3 mbsf (7H), 80.3 mbsf (9H), 99.3 mbsf (11H), and 118.3 mbsf (13H). The computed heat-flow gradient was 70.7°C/km. The bit was pulled back to 168.0 mbsf where the top drive was set back. The drill string was pulled out in stands clearing the seafloor at 2000 hr on 3 October, ending operations at Hole 1125A.

Hole 1125B
The vessel was offset 30 m to the north. To obtain stratigraphic overlap with the previous hole, the bit was lowered by 5 m from the spudding depth of Hole 1123A, and Hole 1125B was spudded with the APC at 2130 hr on 3 October. The recovery indicated a seafloor depth of 1365.6 mbsl. APC coring advanced without incident to 188.8 mbsf. Cores were oriented starting with Core 181-1125B-3H. The hole was deepened with the XCB to 552.1 mbsf, when coring time expired for the leg at 0315 hr on 6 October.

Logging Operations in Hole 1125B
In preparation for logging, an aluminum go-devil was dropped and the hole was circulated with a 60-barrel flush of high-viscosity mud and displaced with 186 barrels of sepiolite. The bit was pulled back to 512 mbsf and the top drive set back. The bit was placed at the logging depth of 96 mbsf. Logging operations began at 0600 hr on 6 October and ended at 1300 hr the same day. Logging operations were limited to only one full pass of the triple combination because of time constraints. There was ~1–2 m of heave throughout operations and the wireline heave compensator was used during all measurements. The hole was logged from the bottom at 524 mbsf to the bit at 78 mbsf (picked up from 96 mbsf). The condition of the borehole was good and the quality of the data was excellent. The hole had a fairly uniform diameter of 12 inches throughout, except near the top where the hole widened to >18 inches.

Following the rigging down from logging, the drill string was recovered and the BHA disassembled for secure stowage during the final transit of the leg. Following the recovery of the beacon, the hydrophones and thrusters were retracted, and the vessel began the transit to Wellington, New Zealand, at 1730 hr on 6 October.

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