The LWD bottom-hole assembly (BHA) consisted of a used 9-7/8 in Smith FDGH (3x14) bit, LWD Bit Sub, LWD Compensated Dual Resistivity (CDR) tool, double pin LWD crossover, LWD Compensated Density Neutron (CDN) tool, LWD crossover sub, 8 each 8-1/4 in drill collars, crossover, Bowen down jars, Bowen up jars, crossover, 2 each 8-1/4 in drill collars, Tapered Drill Collar (TDC), and 6 joints of 5-1/2 in drill pipe.
Hole 1044A was spudded at 1400 hr 27 December 1996. Drilling was initiated at 25 m/hr at a water depth of 4991.4 mbrf based on the precision depth recorder (PDR) reading. It was not possible to determine the mudline with the drill pipe in the soft hemipelagic sediments. Therefore, the PDR reading of 4991.4 mbrf was used for the water depth and the actual water depth will be corrected after analyzing the LWD data. Drilling continued at 25 m/hr down to 5291 mbrf (300 mbsf) where a precautionary wiper trip was made. The proto-décollement was estimated at 200 mbsf and the wiper trip was made from 300 mbsf back to 160 mbsf to allow the top of the BHA to clear the seafloor and also ream the hole in the location of the décollement. No drag or hole problems were encountered during the wiper trip. A 30-bbl sweep of sepiolite mud was used to clean out 9 m of fill that had accumulated at the bottom of the hole and drilling resumed at 25 m/hr. The rate of penetration was increased to 35 m/hr at 5379 mbrf (388 mbsf) to finish the hole more quickly. The drilling rate slowed down dramatically to 4 m/hr at a depth of 5663 mbrf, indicating we had reached basement. Hole 1044A was terminated at 5666 mbrf (675 mbsf) having successfully achieved the depth objective.
The drill string was raised to 5126 m (135 mbsf) and the hole was displaced with 45 bbl of heavy (10.5 lb/gal) mud. The LWD tools were raised to the drill floor where the nuclear sources were removed and the LWD collars were laid out. The beacon was recovered and the bit cleared the rotary table at 0200 hr 30 December ending Hole 1044A.
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