OPERATIONS

Hole 1086A (Proposed Site SCB-E)

The 157-nmi voyage to Site 1086 was accomplished at an average speed of 8.8 kt. The speed of the vessel was adversely affected because of the northward flowing Benguela Current and rough seas. The vessel approached the Global Positioning System coordinates of the site, and a beacon was deployed at 1900 hr on 1 October. Hole 1086A was spudded with the APC at 2240 hr. The seafloor depth was estimated from the recovery of the first core at 781.1 meters below sea level (mbsl). APC coring advanced without incident to 206.2 mbsf (Cores 175-1086-1H through 22H), which was considered refusal depth for piston coring. The recovery for the APC at Hole 1086A was 102.4% (Table 1; also see expanded coring summary table on CD-ROM, back pocket, this volume). Cores were oriented starting with Core 3H. Adara heat-flow measurements were not obtained at this site. The drill string was pulled out of the hole with the bit clearing the seafloor at 0925 hr on 2 October, thereby ending Hole 1086A.

Hole 1086B

The vessel was offset 30 m to the west, and Hole 1086B was spudded with the APC at 1010 hr on 2 October. The recovery of the first core established the seafloor depth at 786.5 mbsl. APC cores 175-1086B-1H through 23H were taken from 0 to 212.1 mbsf, with 101.7% recovery (Table 1). The last core did not achieve a full piston stroke. Cores were oriented starting with Core 4H. The drill string was then retrieved, and with bit cleared the seafloor at 2230 hr. The beacon was recovered, the hydrophones and thrusters were retracted, and the vessel was under way to the next site at 0030 hr on 3 October.

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