The 107-nmi voyage to proposed Site PAT-12C was accomplished in 10.5 hr at an average speed of 10.2 kt. The vessel proceeded directly to the site without conducting a survey. The GPS receiver interface to the DPS was employed to situate the vessel over the coordinates of the new location by 0745 hr on 10 December. A beacon was deployed at 0845 hr. The corrected PDR depth was 5009.4 mbrf.Hole 1222A
After the drill string was deployed to a depth of 4955 mbrf, the driller lowered the bit until the heave compensator appeared to activate, suggesting contact with a firm seafloor at ~5001 mbrf. The drill string was then picked up 5 m to position the bit at a depth of 4996 mbrf. Hole 1222A was spudded with the APC at 1815 hr on 10 December. The seafloor depth indicated by the recovery of the initial core was 5000.1 mbrf, 8.4 m shallower than the PDR depth.
Piston coring in Hole 1222A advanced to an APC refusal depth of 71.9 mbsf with an average recovery of 102.9% (Table T1). Orientation began with Core 3H. The hole was further deepened with four XCB cores until basement contact at a depth of 107.3 mbsf. The average recovery for the 35.4 m XCB cored section was 1.8%.Hole 1222B
After coring operations were completed in Hole 1222A, the drill pipe was pulled out of the hole, and after the bit cleared the seafloor at 1735 hr on 11 December, the vessel was offset 20 east of Hole 1222A. Hole 1222B was spudded with the APC at 1910 hr, and coring advanced to refusal depth (64.4 mbsf; Table T1). As Core 7H was brought on deck, the time allotted for coring expired. The average recovery for the hole was 99.0%. Orientation started with Core 3H.
After coring operations ceased in Hole 1222B, the drill string was recovered, the BHA was disassembled into component parts and secured into the drill collar bays. During the recovery of the drill string, the beacon was successfully recalled. After the drilling equipment was secured, the drilling crew spent 1 hr cutting and slipping of the drilling line. The vessel departed for Honolulu at 1730 hr on 12 December.
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