Site 1272 is the northernmost of our drilling locations on the transect of sites south of the 15°20´N Fracture Zone on the northwestern flank of the inside corner high. The site was targeted based on reviews of videotapes from Faranaut Dives 5 and 2, near the top of the ridge where most of the dive samples were serpentinized peridotite. Site 1272 is ~3.7 nmi north of Site 1271.
Having protected our supply of drill collars during earlier operations, we elected to increase the length of our bottom-hole assembly (BHA) at this site in order to achieve deeper penetration without placing the top of the BHA below the seafloor. Fourteen 8.25-in drill collars (nominally a total of 131 m long) were lowered at the end of the drill string while we positioned the vessel over the Global Positioning System coordinates of our camera survey starting position (Fig. F1). We surveyed along a shallow-dipping, sediment-covered slope and selected a drilling target located in flat terrain between the depths of Faranaut Dive 2 samples FR02-11 and FR02-12 (both serpentinized peridotite) (see Fig. F2). A push-in test with the drill string indicated the sediment cover was only ~1 m thick. Hole 1272A was spudded at 2045 hr on 7 June 2003. Core 1R advanced to 12.9 meters below seafloor (mbsf) (Table T1). Coring continued through Core 27R to a depth of 131.0 mbsf with no difficulty but slow penetration (average = 2.2 m/hr). Since the core we were recovering was clay rich and we encountered several intervals of drilling-induced disturbance, we elected to use core liners inside the core barrels to see if recovery might improve. Core liners were used on Cores 21R and 23R through 27R, and recovery improved to values as high as 79% (average = ~55%, compared to ~30% recovery in similar lithology cored without liners).
The Lamont-Doherty Earth Observatory (LDEO) Drill String Accelerometer tool was deployed with Cores 12R and 14R. After coring to 131 mbsf with little change in the character of the recovered core or in drilling conditions, we decided to terminate coring and begin wireline logging.
Two logging tool strings were deployed in the hole. Both the triple combination (triple combo) and Formation MicroScanner (FMS)-sonic tool strings reached within 6–7 m of the bottom of the hole. With logging completed, the pipe was pulled clear of the seafloor at 0245 hr on 12 May. By 0730 hr, the ship was secured for transit, ending operations at Site 1272.
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