The 271-nmi transit to proposed Site PAT-19A was accomplished in 25.2 hr at an average speed of 10.8 kt. At 1700 hr on 8 November, the vessel slowed to 5 kt, and a short 3.5-kHz survey was made from north to south across the site. Upon conclusion of the 1-hr survey, the vessel came about and returned to site as the thrusters were lowered and the DPS was activated. The vessel was on the GPS coordinates of the new location by 1815 hr. The hydrophones were lowered, and assembly of the BHA began. A beacon was deployed at 1848 hr. The corrected PDR depth was 5340.9 mbrf.Hole 1217A
After the drill string was deployed to a depth of 5330 mbrf, an APC mudline core was attempted from 5335.9 mbrf and resulted in a water core. The driller then lowered the bit until the heave compensator appeared to activate suggesting contact with a firm sea bottom at a bit depth of ~5353 mbrf. The second attempt at a mudline core was made with the bit at 5349.0 mbrf and was successful (0630 hr on 9 November). The seafloor depth indicated by the recovery of the this first core was 5353.0 mbrf and was 12.1 m deeper than the PDR depth.
Hole 1217A was deepened to 99.2 mbsf before it was deemed necessary to switch to the XCB to achieve the objective of obtaining a sample of basement (Table T1). Two of the twelve APC cores (Cores 6H and 8H) did not achieve a full 9.5-m stroke, presumably the result of striking chert. Many of the fully advanced cores also experienced lateral suctioning (flow-in) of sediment below recovered chert nodules. The cores were oriented starting with Core 3H. No heat flow measurements were attempted because of the high probability of damage to the Adara cutting shoe by chert. Hole 1217A APC operations resulted in 99.2 m of cored section with 86.17 m of material recovered (86.9%).
XCB coring (13X through 17X) deepened the hole from 99.2 to 145.2 mbsf, with recovery consisting of chert fragments and a section of nannofossil chalk near basement. A small sample of basalt was obtained in the last core. XCB coring operations deepened Hole 1217A 46.0 m beyond the APC operations and recovered 3.77 m (8.2%). The total recovery for Hole 1217A was 89.94 m, representing 61.9% of the cored interval.Hole 1217B
After the bit cleared the seafloor, the vessel was offset 10 m north of Hole 1217A. The bit was washed to 20 mbsf before we initiated APC operations. Hole 1217B was spudded with the APC at 1545 hr on 10 November. Seven piston cores were obtained over the interval from 20.0 to 86.5 mbsf (Table T1). Many of the cores had flow-in or disturbance below recovered chert nodules. All cores in Hole 1217B were oriented. The average recovery was 92.5%.Hole 1217C
After coring operations in Hole 1217 ceased, the bit was pulled clear of the seafloor, the vessel was moved another 10 m north, and Hole 1217C was spudded at 0630 hr on 11 November. The bit was washed to 32 mbsf, where APC coring operations began. Five oriented cores were taken over the interval from 32.0 to 79.5 mbsf (Table T1). The average recovery was 98.6%, but many cores suffered from flow-in.
After coring operations ceased at Site 1217, the drilling equipment was secured, and the beacon was successfully recovered. The 24-hr transit to the next site (PAT-8) transit to the next site began at 1545 hr on 12November.
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