Hole 1145A
Hole 1145A was spudded with the APC at 0245 hr on 19 March. The seafloor depth was inferred from the recovery of the first core as 3187.1 m. Piston coring advanced to 125.0 mbsf with an average recovery of 100.1%. The cores were oriented starting with Core 4H. During piston coring, heat-flow measurements were obtained at 30, 58, 96, and 200 mbsf. The last measurement was made with the Davis-Villinger temperature probe (DVTP). A temperature gradient of 90°C/km was calculated from these data. The hole was deepened with the XCB to the target depth of 200.0 mbsf. The XCB average recovery was 81.9%; the average recovery for this hole was 93.3%. Only a trace amount of methane was detected in the cores.
Hole 1145B
The vessel was offset 10 m west of Hole 1145A, and Hole 1145B was spudded with the APC at 0145 hr on 20 March. The seafloor depth, inferred from the recovery of the first core, was 3185.9 m. Piston coring advanced to 120.6 mbsf with an average recovery of 99.5%. The cores were oriented starting with Core 3H. The hole was deepened to the target depth of 200.0 mbsf with the XCB. The XCB-cored portion of the hole averaged only 74.8% because of zero recovery in one of the core barrels (20X). The average recovery for the hole was 89.7%.
Hole 1145C
The vessel was offset 10 m west of Hole 1145B, and Hole 1145C was spudded with the APC at 2015 hr on 20 March. The seafloor depth was inferred to be 3187.9 m. Piston coring advanced to 121.6 mbsf with an average recovery of 101.4%. The cores were oriented starting with Core 3H. The hole was deepened to the target depth 198.4 mbsf with the XCB; the average XCB recovery was 86.0%. The average recovery for the hole was 95.4%.
The total core recovered at this site was 555.2 m, or 92.8% of the cored interval of 598.1 m. The bit was at the plane of the rotary table by 1630 hr on 21 March, and the vessel began the 78-nmi voyage to Site 1146.