After a day of speeches by Yokosuka officials and ODP luminaries and music by the Tahoka Junior High School orchestra, the JOIDES Resolution departed Yokosuka Pier 2 at 0745 hr on 22 July 2000 (all times Universal Time Coordinated + 9 hr) headed for proposed Site WP-2A, ~1000 nmi distant. The ship made good time, traveling at an average of 12.5 kt, collecting magnetic and echo-sounder data en route, arriving at the site at 2116 hr on 25 July after a transit of 85 hr, 31 min. Because of time pressures and the fact that proposed Site WP-2 is located at the intersection of two Global Positioning System (GPS)-navigated multichannel seismic lines, it was decided that additional seismic profiling work would be of limited utility and no additional site survey data were collected. Upon reaching the site, the Resolution slowed, the thrusters were lowered, and the ship was positioned by GPS over the site. Two beacons were dropped at 2215 hr on 25 August to establish Site 1179.
By 2215 hr on 25 July, the advanced hydraulic piston corer/extended core barrel (APC/XCB) bottom-hole assembly (BHA) was being lowered. The first APC core extended prematurely and returned empty. Nonetheless, it was discovered that the core cutting shoe had traces of mud, indicating that the BHA was near the seafloor. The drill string was lowered an additional 6 m, and the next APC core fired successfully. Upon retrieval, this core was found to be completely full, having overshot the mudline. The core was curated as Core 1H, but it was necessary to establish the mudline by pulling the pipe up, so Hole 1179A was terminated at 1615 hr on 26 July (Table T1).
After raising the drill string by 4 m, Hole 1179B was spudded with the APC/XCB BHA at 1700 hr on 26 July. The core barrel returned with a valid mudline and 7.6 m of siliceous ooze, establishing the seafloor at 5574.9 meters below rig floor (mbrf). APC coring proceeded ahead to Core 6H. The tensor tool was run on Cores 4H through 6H, and the Adara temperature tool collected data on Core 4H. In addition, a perfluorocarbon tracer (PFT) injection was made into the drill pumps during Core 5H coring as a microbiological test for drilling fluid contamination in the cores.
Trouble occurred during the deployment of what would have been Core 7H. The drill-string accelerometer (DSA) tool, deployed for the first time in a redesigned configuration, caused the core barrel to become lodged in the drill string ~650 m below the ship. Efforts to free the core barrel were ineffective, and it became necessary to pull up 18 stands of pipe to retrieve the stuck tool. This ended Hole 1179B, after we reached a depth of 55.1 meters below seafloor (mbsf).
Upon the completion of Hole 1179B, problems were encountered with the core winch that required repair, causing a delay of several hours. The ship was offset 10 m south (Fig. F5), and Hole 1179C was spudded at 1400 hr on 27 July with Core 1H reestablishing the mudline at 5576.7 mbrf. The interval from 5.8 to 48.8 mbsf was drilled without coring to save time. Coring resumed at 48.8 mbsf with Core 2H, positioned to overlap the cores of Hole 1179B by 5 m. APC cores were retrieved from 48.8 to 266.8 mbsf (Cores 2H through 24H), recovering Neogene siliceous clays and oozes with ash layers. The tensor tool was used to orient Cores 4H-11H and 13H-24H; the Adara temperature tool was run on Cores 3H, 6H, 9H, and 12H; and a PFT test was run on Core 21H. During coring of Core 24H, the formation became too stiff for further use of the APC. Coring was switched to the XCB, and Cores 25X through 27X were cut between 266.8 and 292.9 mbsf. An unsuccessful PFT test was run on the last XCB core. The cutting time for Core 27X increased dramatically, and only chert fragments were recovered. It was decided that the XCB was not the optimal coring apparatus for the chert-infested layers expected at greater depth, so Hole 1179C was terminated at 1200 hr on 29 July, having cored to a depth of 292.9 mbsf.
The drill pipe was raised to pull out of the hole, and the ship was offset 30 m to the east of Hole 1179C. A jet-in test for the casing was performed, and then the drill string was recovered. Drilling operations were suspended briefly while ship's personnel lowered the video camera to detorque a new coaxial cable.
After moving the ship ~30 m north of Holes 1179A and 1179B, a rotary core barrel (RCB) BHA was assembled and run to the seafloor. Hole 1179D was spudded at 0300 hr on 31 July. Drilling continued with a center bit to a depth of 281 mbsf, ~11 m above the depth at which the previous hole had been terminated. RCB coring commenced and chert layers were encountered in the next nine cores. Apparently the chert layers were interbedded with soft sediments, because only chert fragments were recovered in this interval; the speculation is that the chert layers fragmented and ground up the soft sediments, which were in turn flushed away by the circulated fluid. Of the 86.5 m of cherty layers penetrated, only 5.8 m of chert fragments was recovered.
Core 10R brought a surprise: basalt. The contact with igneous basement was expected at a depth of >400 m, based on seismic reflection data. Drillers estimated the basement depth at 375 mbsf by the depth of the drill pipe when increased resistance was encountered. Coring proceeded in basaltic rock until 100 m of basement penetration had been achieved (Core 22R), making the total depth of Hole 1179D 475.0 mbsf. Recovery in the basaltic section ranged from 18-19 cm (Cores 15R and 16R) to 6.42 m (Core 22R), with an average of 44%. The penetration rate in basement averaged 1.9 m/hr.
After coring ended, the bit was released at 0215 hr on 5 August, a wiper trip was made to ream the hole, and sepiolite mud was pumped into the hole in preparation for downhole logging. Rigging for logging was completed by 0730 hr, and the Schlumberger triple-combination (triple combo) tool string was run down with the addition of the Lamont-Doherty Earth Observatory (LDEO) temperature tool at the bottom and an additional gamma-ray tool at the top. The tool string passed down to 300 mbsf and was run back up the hole ~100 m for calibration purposes. Upon resuming its downward trip, the tool was unable to pass 253 mbsf; the hole evidently collapsed or bridged. The logging tool string was returned to the derrick and rigged down at 2245 hr on 5 August. A cement plug was pumped into the hole to seal it, and the drill string was tripped to the surface, the end reaching the rotary table at 1150 hr on 6 August.
While the drill string was being disassembled and pulled back to the surface, the ship was offset ~70 m to the south and 30 m to the east of Hole 1179D. A reentry cone was assembled and centered in the moonpool. The casing shoe joint and four additional joints of 16-in casing were made up and attached to the cone. A BHA with a 14.75-in tricone drill bit was made up and engaged with the hanger assembly of the casing string. The reentry cone and casing assembly were run to the seafloor and landed at 1115 hr on 7 August. Within 1.75 hr, the 64 m of casing was jetted in and the running tool was released from the drill string. By 0230 hr on 8 August, the drill string was recovered.
During the upward trip of the drill pipe from the casing deployment, the vibration-isolated television (VIT) camera was lowered to image an acoustic release test. The camera winch had difficulty raising the camera frame in depths greater than ~4600 m. To make sure that the new coaxial cable was not wrapping around the drill string, the cable was detorqued by lowering the camera sled to successively greater depths and reeling it back in. This exercise was finished by 1400 hr on 8 August, and the crew began making up the 14.75-in drilling assembly to be used in drilling Hole 1179E.
By 0200 hr on 9 August, the camera and drill string were in position to attempt reentry and after 5 hr, 15 min, the reentry was accomplished. At 1015 hr on 9 August, drilling commenced. Igneous basement was contacted at 5948 mbrf (~371 mbsf), ~4 m higher than at Hole 1179D. The 14.75-in hole was terminated at 2330 hr on 10 August, after penetrating about 28 m into basement. The hole was swept with sepiolite mud, and a wiper trip was made to a depth of 80 mbsf. After additional flushing of the hole with sepiolite mud, the drill string was recovered. The reentry cone was cleared at 0645 hr on 11 August, and the bit cleared the rotary table at 1830 hr on the same day.
A 10.75-in casing string was assembled for insertion inside the borehole. A total of 30 casing joints were assembled, including a cementing shoe on the bottom and a casing hanger on top. The BHA was made up and attached to the casing, and the downward trip began. At 0600 hr on 12 August, it was discovered that the casing was constructed with one joint too many. The drill string was pulled back to the surface, and the mistake was corrected. By 0045 hr on 13 August, the drill pipe and VIT camera were in position for reentry.
At 0230 hr that same day, the hole was reentered for the second time. The casing hanger landed without incident with the casing shoe at a depth of 5970 mbrf (393.4 mbsf). Latch engagement was verified and the casing was cemented in place with 50 bbl of cement slurry. The running tool was released, and the pipe trip back to the surface began. The pipe trip was slowed again by difficulties with the winch raising the VIT camera frame. However, all tools were clear of the rotary table by 0300 hr on 14 August.
Drilling at Hole 1179E was interrupted owing to inclement weather. Forecasts predicted that a tropical storm, named Ewiniar, would turn and head toward the site location without leaving enough time to make a round trip of the pipe and do a significant amount of drilling.
The drill collars were laid out in preparation for bad weather while the ship stood by at Site 1179 waiting on weather forecast updates. At 1530 hr on 14 August, the ship began moving east, out of the path of the storm, which was predicted to cross the site. By 15 August, the storm had intensified into a typhoon and the ship turned south to move farther out of the storm path. When the storm moved north, rather than east, the ship turned north-northeast at 0700 hr on 17 August to head back to Site 1179 in hopes of reoccupying the site as soon as the storm passed. As the ship approached the site, the storm began to lose strength and continued a slow northward drift. At 0930 hr on 18 August, thrusters were lowered and the Resolution reoccupied Site 1179, having lost ~104 hr to weather. During its flight from the typhoon, the Resolution covered 909 nmi, collecting magnetic and bathymetry data all the while. Ewiniar stayed northwest of the site, ~220 nmi away, until it faded to a tropical depression and finally to a low-pressure cell that lost its identity.
The drill string was assembled and lowered to the reentry cone with the VIT camera. After 45 min of attempts, Hole 1179E was reentered at 2230 hr on 18 August. Once the camera frame was recovered, the pipe trip was resumed and by 0315 hr on 19 August, the bit had been lowered to 5965 mbrf (388 mbsf). The cement shoe was drilled out in ~3 hr, and drilling in basement commenced. Drilling continued to a depth of 6052 mbrf (475 mbsf), which was reached at 0115 hr on 21 August. A wiper trip was made through the bottom of the hole and sepiolite mud was pumped in. The drill string was tripped back to 56 mbsf, where 15 min was taken to flush the upper casing and reentry cone. The pipe trip then continued until the bit reached the rotary table at 1445 hr on 21 August. Hole 1179E was complete and preparations began for installing the seismometer assemblies.
After the drill string was on board, construction began on the 4.5-in casing to hold the seismometers inside the borehole. The two seismometers were attached to the bottom part of the casing string, and electrical cables were connected. The cables were run up the outside of the casing and attached with tie wraps and tape. Centralizer spacers were attached to the casing every 1.5 m. Technicians and crew members continued with this assembly for ~11 hr, until 0200 hr on 22 August. The riser hanger was mated to the riser, and the cables were cut to length and terminated, a process that continued until 2200 hr. Installation and the connection of the electrical package (G-box) to the seismometer cables required another 3.5 hr.
The casing and seismometers were run to the seafloor and were positioned for reentry at 0945 hr on 23 August. Reentry was accomplished at 1110 hr, and the casing was run in the hole without incident. Fifty barrels of cement slurry were pumped down the drill string to the casing to cement the seismometer assembly to the rock of the borehole walls. The VIT camera frame was winched back to the ship so that the battery frame could be deployed.
Assembly of the battery frame halves around the drill string over the moonpool commenced at 1830 hr and was finished by 0215 hr on 24 August. The battery frame was attached to a bridle hung from the logging line. Because it was too dark to see obstructions in the moonpool, deployment was delayed until daylight at 0415 hr. The battery frame was lowered through the moonpool without incident, despite occasional surges from the ship's heave. The battery frame landed at 0915 hr, and an acoustic signal was sent to the release mechanism, which confirmed having released the frame. By 1230 hr, the logging line was recovered and the VIT camera was lowered for a visual inspection of the installation. The battery frame was found to have landed properly. At 1415 hr, all hands watched the J-tool rotate and release the casing, successfully ending the seismometer deployment. The VIT camera was recovered, and the drill string was tripped back to the ship. The BHA cleared the rotary table at 0515 hr, and the derrick was readied for transit.