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Port Call—Honolulu

Leg 199 began at 2200 hr on 23 October 2001 when the first line was passed ashore at Pier 32A in Honolulu, Hawaii. At 0830 hr on 28 October, after 5 days of port call activities, the last line was released and the transit to the first site of the leg began.

Transit to Site 1215 (PAT-15D)

After clearing the harbor under the pilot's instructions, the vessel transited the Honolulu channel passing within a couple nautical miles of Diamond Head. After proceeding into the open ocean, the vessel speed decreased slightly because the transit direction was directly into a 6 m sea/swell. Toward the afternoon of 29 October, the wind and sea conditions began to moderate and the vessel motion decreased with a concomitant increase in speed. At 1945 hr on 30 October, the vessel speed was reduced to 5 kt and a 5-mi 3.5-kHz survey was made over proposed Site PAT-15D. The 625-nmi voyage to Site 1215 required 58.5 hr at an average speed of 10.7 kt.

Site 1215

At the conclusion of the 3.5-kHz survey, the thrusters were extended, and the vessel returned to the site coordinates using the global positioning system (GPS) interface to the dynamic positioning system (DPS). At 2100 hr on 30 October, the vessel was over the prospective site and the drilling crew began the assembly of the BHA. A beacon was deployed at 2144 hr.

Hole 1215A

After the vessel settled on location, the corrected precision depth recorder (PDR) depth of 5399.4 meters below rig floor (mbrf) of (referenced to the dual elevator stool) was obtained. After the BHA was made up, the drill string was then deployed to a depth of 5042 mbrf, at which point the armature shaft of the forward M89 traction (drawworks) motor broke. A spare motor was installed, tested, and fully operational by 2400 hr on 31 October 2001.

Hole 1215A was spudded with the APC at 0145 hr on 11 July. The seafloor depth indicated by the recovery of the initial core was 5406.3 mbrf. Piston coring advanced to 69.2 mbsf where the formation became too indurated to continue with the APC system. APC coring resulted in 68.22 m of core recovered from a 69.2 m hole (98.6% recovery) (Table T1). Cores 4H through 9H were oriented with one Adara heat flow measurement attempted at 29.7 mbsf (Core 4H). Further heat flow measurements were not made because the cutting structure of the Adara shoe was damaged by chert, and it was obvious that additional runs in this formation would further deplete the limited stock of this hardware.

The XCB was deployed and advanced from 69.2 to 75.4 mbsf. Most of the 80 rotating min for this core were used to advance the last half meter. When the core barrel was retrieved, several basalt fragments were removed from the core catcher, indicating that the objective of coring into basaltic basement was achieved. The one XCB core in Hole 1215A advanced 6.2 m with a recovery of 0.05 m (0.8% recovery). Overall, 68.27 m of core was recovered from 75.4 m of cored section at Hole 1215A.

Hole 1215B

After Hole 1215A operations ceased, the bit was pulled above the seafloor, and the vessel was offset 20 m south of Hole 1215A. Hole 1215B was spudded with the APC at 0900 hr on 2 November. A seafloor depth of 5406.0 mbrf was inferred by the recovery in the initial core. Piston coring advanced to APC refusal at a depth of 57.0 mbsf with 58. 23 mbrf

of core recovered (102.2% recovery). Cores 3H through 8H were oriented. The XCB was used to advance the hole from 57.0 to 82.8 mbsf. Contact with basement was confirmed when basalt fragments were removed from the core catcher of Core 11X. Only 0.72 m of core was recovered from the 25.8-m XCB-cored interval (2.8% recovery). Overall, the average recovery for Hole 1215B was 71.2% (Table T1).

After coring operations ceased in Hole 1215B, the drill string was recovered and the BHA was dismantled in preparation for the transit to Site 1216. The beacon was successfully recalled and recovered. After the drilling equipment was secured, the vessel departed for Site 1216 at 1430 hr on 3 November.

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