IODP

doi:10.2204/iodp.pr.329.2011

Operations

During Expedition 329 we conducted operations in 42 holes at 7 sites ranging from 3749 to 5707 meters below sea level (mbsl). We cored 1321.8 m of sediment and basalt and recovered 1168.8 m of core (Table T1). Downhole logs were collected in one hole. Here we describe the coring and logging operations at each of these sites. The overall time distribution included 5.1 days in port, 27.26 days in transit, and 33.7 days on site. We covered 6655 nmi, of which 4503 nmi was transit between the first and the last site. All times in the operations section are given in local ship time unless otherwise noted. For most of the expedition, local time was Universal Time Coordinated –10 h.

Papeete port call

Expedition 329 began with the first line ashore on Papeete, Tahiti (French Polynesia), at 0734 h on 7 October 2010. The first Tahiti port call for the JOIDES Resolution included refueling after the long journey from Victoria, British Columbia. After refueling, the ship was secured by tugboats and moved to the EPI North Pier, across from the town center, on 8 October. USIO staff, the expedition Co-Chiefs, and some members of the Scientific Party boarded the ship on 9 October to start setting up third-party instrumentation in the ship's laboratories in preparation for the expedition. The rest of the Science Party moved onboard on 10 October. Port call lasted 5.1 days.

Transit to Site U1365

The JOIDES Resolution departed Papeete for the 982 nmi journey to Site U1365 in the morning of 12 October 2010. The vessel sailed at full speed, averaging 11.5 kt, and arrived at Site U1365 at 0030 h on 16 October. The position reference was a combination of GPS signals. Although an acoustic beacon was deployed, it was not used for positioning at this site because of an electronic malfunction in the dynamic positioning system. The positioning beacon was deployed at 0805 h on 17 October and recovered at 2044 h on 21 October.

Site U1365

Five holes were cored at Site U1365. The first four holes were cored with the advanced piston coring (APC) system. The fifth and final hole was drilled with a 9⅞ inch rotary core bit. Downhole logging was originally scheduled for this site but was canceled when the overall depth of the hole was reduced because of the low penetration rates with the rotary core barrel (RCB) bit. As a proxy for microbial contamination, perfluorocarbon tracer (PFT) was continuously injected into the drilling fluid for all coring of Holes U1365B–U1365E. The advanced piston corer temperature tool (APCT-3) was deployed 8 times on the APC system, and usable data was recovered 7 times. On one of the tool runs, the data was lost while trying to recover it from the tool. For this site, APC system recovery was 95.2% and RCB system recovery was 74.5%. Overall core recovery for this site was 90.8%. A total of 55 cores were recovered after coring 251.1 m. The total length of core recovered was 228.07 m.

Hole U1365A

Rig floor operations started at 0030 h on 16 October 2010. The trip to the seafloor was without incident while measuring and drifting the tubulars and assembling the bottom-hole assembly (BHA). The top drive was picked up, the drill string was spaced out, and a washdown hole was drilled to determine depth of basement. The center bit was pulled by wireline, the vessel was offset 20 m west, and the top drive was spaced out to spud Hole U1365A. After making up the first APC core, the core barrel was run to bottom on the wireline and Hole U1365A was spudded at 0530 h on 17 October. Seafloor depth was established with a mudline core at 5706.3 meters below rig floor (mbrf). Nonmagnetic core barrels and the Flexit tool were used for the first 4 cores and APCT-3 temperature measurements were taken on Cores 329-U1365A-1H, 3H, and 4H. APC continued until basement was reached at 75.5 mbsf. A total of 26 cores were taken in Hole U1365A, with a total recovery of 74.06 m (98.1%). All cores after Core 4H were incomplete strokes, and the recovery was slowed by a very thick layer of chert formation from ~42 to 63.5 mbsf. After reaching basement on Core 26H, the bit was tripped back to just above the seafloor, ending Hole U1365A at 0845 h on 19 October.

Hole U1365B

Hole U1365B was offset 20 m north of Hole U1365A and was spudded at 1010 h. The mudline core established seafloor depth at 5705.4 mbrf. APC continued until 42.5 mbsf. Temperature measurements were taken with the APCT-3 on Cores 329-U1365B-3H, 4H, and 5H, although the data on Core 3H was lost trying to download the data from the tool. The center bit was then deployed and the formation was drilled from 42.5 to 63.5 mbsf. The center bit was pulled and APC continued until basement was reached at 75.6 mbsf. A total of 8 cores were taken with a total recovery of 55.79 m (102.2%). All cores after Core 5H were incomplete strokes and a 21 m section of hole was drilled to avoid coring a very thick layer of chert formation from ~42 to 63.5 mbsf. The drill string was tripped to just above the mudline, clearing the sea floor at 0640 h on 20 October and ending Hole U1365B.

Hole U1365C

After offsetting the vessel 20 m north, Hole U1365C was spudded at 0940 h on 20 October and advanced with the APC system to 37.5 mbsf before encountering the first hard chert layer. Temperature measurements were taken with the APCT-3 on Cores 329-U1365C-3H and 4H. The center bit was then dropped and the subsequent drilled interval ended again at 63.5 mbsf after advancing 26 m. The center bit was pulled and the APC system was redeployed and advanced by recovery until basement was encountered at 74.8 mbsf. A total of 8 cores were taken with a total recovery of 39.67 m (81.3%). All cores after Core 4H were incomplete strokes. The drill string was then tripped to just above the mudline, clearing the seafloor at 0435 h on 21 October and ending Hole U1365C.

Hole U1365D

After offsetting the vessel 20 m east, Hole U1365D was spudded at 0540 h on 21 October. The hole was advanced with the APC system for 2 cores to 19 mbsf and 18.89 m of sediment was recovered, for an overall recovery of 99.4%. After the second core, the drill string was tripped to surface and the bit cleared the rotary table at 2030 h, ending Hole U1365D.

Hole U1365E

The objective at Hole U1365E was to drill and core through the sediment/basalt interface and ~100 m into the basaltic basement. However, we cored ~50 m of basement with good recovery, did not capture the sediment/basement interface, and ran out of allocated time because of slow coring rates (<1 m/h). After a 20 m offset to the south, Hole U1365E began at 2030 h on 21 October. The BHA was set back, the APC bit was removed, and the rotary core bit and RCB coring system were assembled in preparation for running the new RCB BHA. The BHA was being assembled when a worrisome noise was noticed on the rig floor. Subsequent investigation revealed a failed crown block sheave bearing on the Number 2 sheave. After discussions with onboard staff, Transocean management, Transocean engineering, and the original equipment manufacturer, a decision was reached to restring the blocks to a 10-part configuration, isolating the damaged sheave from the system. Work was completed on the field modification and repair at 0600 h on 23 October. The BHA was then run into the hole, followed by the drill pipe, and the top drive was picked up and the drill string was spaced out to spud Hole U1365E. Water depth was recorded at 5705 mbrf using the offset from the previous hole. The center bit was deployed and Hole U1365E was spudded at 2210 h on 23 October. At 71 mbsf, the center bit was pulled and the RCB was dropped and coring began. RCB coring continued from 71 to 124.2 mbsf with good recovery. Because of extremely slow penetration rates, after the first core, half cores were cut and retrieved. A total of 53.2 m was cored and 39.66 m was recovered (74.6% recovery). Contamination testing was done with fluorescent microspheres (as well as PFT) on all cores after the sediment/basement interface core. The drill string was then tripped back to the rig floor and secured for the 494 nmi transit to the next site, ending Hole U1365E and Site U1365 at 2115 h on 27 October.

Transit to Site U1366

After a 48.85 h transit from Site U1365, covering 494 nmi and averaging 10.1 kt, the speed was reduced and thrusters and hydrophones were lowered. Speed was less than expected because two of the propulsion motors on the starboard shaft were offline with failed field coils. Dynamic positioning was initiated over Site U1366 at 2215 h on 29 October 2010. The position reference was a combination of GPS signals. No acoustic beacon was deployed, but a beacon remained on standby in the event of loss of GPS satellite coverage. Whereas automatic input into the dynamic positioning system was not possible, it was possible to manually hold the vessel in position to clear the seafloor with the BHA, if necessary.

Site U1366

Six holes were drilled or cored at this site. The first hole was a washdown hole drilled with the center bit in order to establish the sediment depth. The next five holes were cored and drilled with the APC system. PFT was continuously injected into the drilling fluid for all coring of Holes U1366B–U1366F. The APCT-3 was not deployed because the sediment thickness was only ~20 m. APC system recovery for Site U1366, was 100.6%. Extended core barrel (XCB) recovery was 0%. A total of 14 cores were attempted after coring 97.9 m. The total length of core recovered from this site was 96.45 m for a recovery of 98.5%.

Hole U1366A

Rig floor operations commenced at 2215 h on 29 October 2010. The trip to the seafloor was uneventful. The top drive was picked up, and the drill string was spaced out and spudded at 0815 h. The PFT pump was turned on to distribute PFT evenly throughout the fluid in the drill string. The washdown hole was drilled to determine depth of basement. Mud line was established at 5146.0 mbrf by tagging with the bit. After drilling down, basement was established at 17.8 mbsf. The bit was pulled back, clearing the seafloor at 0845 h and ending Hole U1366A.

Hole U1366B

After clearing the seafloor, the center bit was pulled by wireline, the vessel was offset 20 m west, and the drill string was spaced out to spud Hole U1366B. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1366B was spudded at 1045 h on 30 October. Seafloor depth was established with a mudline core at 5141.8 mbrf. APC coring continued to 17.2 mbsf. Two cores were taken with a total recovery of 17.31 m (100.6% recovery). After Core 329-U1366A-2H, the bit was tripped back to just above the seafloor, ending Hole U1366B at 1300 h on 30 October.

Hole U1366C

Hole U1366C began at 1300 h when the APC assembly cleared the seafloor after completing Hole U1366B. After offsetting the vessel 20 m north, Hole U1366C was spudded at 1345 h on 30 October and advanced with the APC system to 25 mbsf before encountering basement. Seafloor was established at 5140.5 mbrf. Three cores were taken with a total recovery of 25.42 m (101.7% recovery). The drill string was then tripped to just above the mudline, clearing the seafloor at 1715 h on 30 October and ending Hole U1366C.

Hole U1366D

Hole U1366D began at 1715 h when the APC assembly cleared the seafloor after completing Hole U1366C. After offsetting the vessel 20 m east, Hole U1366D was spudded at 1800 h on 30 October and advanced with the APC system for three cores to 18.9 mbsf with an 18.86 m recovery (99.8% recovery). Seafloor was established at 5137.1 mbrf. After APC refusal, an XCB core barrel was deployed and advanced 2 m into the formation without any recovery. After the last core, the drill string was tripped to just above the mudline, clearing the seafloor at 2330 h on 30 October and ending Hole U1366D.

Hole U1366E

After clearing the seafloor, the vessel was offset 40 m west and the drill string was spaced out to spud Hole U1366E. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1366E was spudded at 0015 h on 31 October. Seafloor depth was established with a mudline core at 5138.8 mbrf. APC coring consisted of a single mudline core to 4.7 mbsf. One core was taken with a total recovery of 4.71 m (100.2% recovery). Core 329-U1366E-1H was recovered with a shattered liner and was not acceptable for microbiology. Hole U1366E ended with the first APC core at 0015 h on 31 October.

Hole U1366F

Hole U1366F began at 0015 h after the mudline core of Hole U1366E was completed. After offsetting the vessel 20 m west, Hole U1366F was spudded at 0130 h on 31 October and advanced with the APC coring system for four cores to 30.1 mbsf with a 30.15 m recovery. Overall recovery in Hole U1366F was 100.2%. After the last core, the drill string was tripped to surface and all drilling equipment was secured at 1815 h on 31 October, ending Hole U1366F and beginning the 1019 nmi transit to the next site.

Transit to Site U1367

After a 100.75 h transit from Site U1366, covering 1019 nmi and averaging 10.1 kt, the speed was reduced and thrusters were lowered. Speed was less than expected because two of the propulsion motors were offline, one on the starboard shaft and one on the port shaft, both with failed field coils. Dynamic positioning was initiated over Site U1367 at 2304 h on 4 November 2010. The position reference was a combination of GPS signals. No acoustic beacon was deployed, but a beacon remained on standby in the event of loss of GPS satellite coverage. Whereas automatic input into the dynamic positioning system was not possible because of a system malfunction, it was possible to manually hold the vessel in position to clear the seafloor with the BHA if necessary.

Site U1367

Six holes were drilled or cored at this site. The first hole was a washdown hole drilled with the center bit in order to establish the sediment depth of 21.2 mbsf. The next four holes were cored with the APC system. The last remaining hole was drilled and cored with the RCB system ~33.5 m into basement. The APCT-3 was not deployed because of the sediment depths. PFT was pumped in for the entire drilling/coring interval until the last core was on deck. APC system recovery for Site U1367 was 98.1%. RCB system recovery was 11.2%. A total of 20 cores were attempted while coring 137.4 m. The total length of core recovered at this site was 101.34 m (73.8% recovery).

Hole U1367A

Rig floor operations commenced at 2300 h on 4 November 2010. The trip to the seafloor was uneventful. The top drive was picked up and the drill string was spaced out and spudded at 0740 h on 5 November. The PFT pump was turned on to displace the drill string with the contamination testing fluid. The washdown hole was drilled to determine depth of basement. Mud line was established at 4302.0 mbrf by tagging with the bit. After drilling down, basement was established at 21.2 mbsf. The bit was pulled back above the seafloor, clearing the seafloor at 0810 h on 5 November and ending Hole U1367A.

Hole U1367B

After clearing the seafloor, the center bit was pulled by wireline, the vessel was offset 20 m west, and the drill string was spaced out to spud Hole U1367B. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1367B was spudded at 1000 h on 5 November. Seafloor depth was established with a mudline core at 4300 mbrf. APC coring continued to 22.3 mbsf. Four cores were taken with a total recovery of 22.31 m (100.0% recovery). After Core 329-U1367B-4H, the bit was tripped back to just above the seafloor, ending Hole U1367B at 1440 h. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing.

Hole U1367C

Hole U1367C began at 1440 h when the APC assembly cleared the seafloor after completing Hole U1367B. After offsetting the vessel 20 m north, Hole U1367C was spudded at 1520 h on 5 November and advanced with the APC system to 26.7 mbsf before encountering basement. Seafloor was established at 4299.3 mbrf. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. Four cores were taken with a total recovery of 27.01 m (101.2% recovery). The drill string was then tripped to just above the mudline, clearing the seafloor at 2005 h and ending Hole U1367C.

Hole U1367D

Hole U1367D began at 2005 h on 5 November when the APC assembly cleared the seafloor after completing Hole U1367C. After offsetting the vessel 20 m east, Hole U1367D was spudded at 2205 h and advanced with the APC system for four cores to 25.5 mbsf with a 24.54 m recovery (96.2%). Seafloor was established at 4299.1 mbrf. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. The drill string was tripped to just above the mudline, clearing the seafloor at 0255 h on 6 November and ending Hole U1367D.

Hole U1367E

Hole U1367E began at 0255 h on 6 November when the APC assembly cleared the seafloor after completing Hole U1367D. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1367E was spudded at 0340 h. Seafloor depth was established with a mudline core at 4298.7 mbrf. The APC system was used to take three cores to 24.4 mbsf with a 23.15 m recovery (94.9%). PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. The drill string was tripped to the surface, clearing the rotary table at 1400 h and ending Hole U1367E.

Hole U1367F

After a 20 m offset to the south, Hole U1367F began on 6 November at 1400 h when the bit cleared the rotary table after tripping out of Hole U1367E. The BHA was set back, the APC bit was removed, and the rotary core bit and rotary coring system were assembled in preparation for running the new RCB BHA. The BHA was run into the hole followed by the drill pipe. The top drive was picked up and the drill string was spaced out to spud Hole U1367F. Water depth was recorded at 4300 mbrf using the BHA tag depth. The center bit was deployed and Hole U1367F was spudded at 2345 h. At 17 mbsf, the center bit was pulled and the RCB was dropped and coring began. RCB coring continued from 17 to 55.5 mbsf with poor recovery. A total of 38.5 m was cored with a recovery of 4.33 m of core. RCB system recovery in Hole U1367F was 11.2%. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. Microspheres were also deployed on all RCB cores in Hole U1367E. The drill string was tripped back to the rig floor and secured for the 793 nmi transit to the next site, ending Hole U1367F and Site U1367 at 0545 h on 9 November.

Transit to Site U1368

After an 80.75 h transit from Site U1367, covering 793 nmi and averaging 9.8 kt, a sonar survey was initiated over Site U1368. The survey essentially replicated the lines of the original site survey in order to confirm depths of bottom and hard returns under the seafloor. After the survey was completed at 1515 h, the speed was reduced and thrusters were lowered. Speed was less than expected because one of the propulsion motors was offline and the vessel sailed most of the voyage into head winds and seas. Dynamic positioning was initiated over Site U1368 at 1545 h on 12 November 2010. The reference position was a combination of GPS signals. No acoustic beacon was deployed, but a beacon remained on standby in the event of a loss of GPS satellite coverage. Whereas automatic input into the dynamic positioning system was not possible because of a system malfunction, it was possible to manually hold the vessel in position to clear the seafloor with the BHA if necessary.

Site U1368

Six holes were drilled or cored at this site. The first hole was a washdown hole drilled with the center bit in order to establish the sediment depth of 13.6 mbsf. The next four holes were cored with the APC system. The last hole was drilled and cored with the RCB system 115.1 m below seafloor and into basement. The APCT-3 was not deployed because of the shallow sediment depth. PFT was pumped for the entire drilling/coring interval until the last core was on deck. APC system recovery for Site U1368 was 99.8%. RCB system recovery was 27.6%. A total of 23 cores were attempted while coring 173 m. The total length of core recovered at this site was 89.52 m (51.7% recovery).

Hole U1368A

Rig floor operations commenced at 1545 h on 12 November 2010. The trip to the sea floor was uneventful. The top drive was picked up and the drill string was spaced out and spudded at 0130 h on 13 November. The PFT pump was turned on to displace the drill string with the contamination testing fluid. The washdown hole was drilled to determine depth of basement. Mud line was established as 4302.0 mbrf by tagging with the bit. After drilling down, basement was established at 13.6 mbsf. The bit was pulled back above the seafloor, clearing the seafloor at 0200 hours and ending Hole U1368A.

Hole U1368B

After clearing the seafloor, the center bit was pulled by wireline, the vessel was offset 20 m west, and the drill string was spaced out to spud Hole U1368B. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1368B was spudded at 0330 h on 13 November. Seafloor depth was established at 3750 mbrf with a mudline core. APC coring continued to 16.0 mbsf. Three cores were taken with a total recovery of 15.84 m for an overall recovery in Hole U1368B of 99.0%. After Core 329-U1368B-3H, the bit was tripped back to just above the seafloor, ending Hole U1368B at 0655 h on 13 November. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing.

Hole U1368C

Hole U1368C began at 0655 h when the APC assembly cleared the seafloor after completing Hole U1368B. After offsetting the vessel 20 m north, Hole U1368C was spudded at 0730 h on 13 November and advanced with the APC system to 16.3 mbsf before encountering basement. Seafloor was established at 3749.5 mbrf. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. Two cores were taken with a total recovery of 16.34 m for an overall recovery in Hole U1368C of 100.2%. The drill string was tripped to just above the mudline, clearing the seafloor at 0915 h and ending Hole U1368C.

Hole U1368D

Hole U1368D began at 0915 h on 13 November when the APC assembly cleared the seafloor after completing Hole U1368C. After offsetting the vessel 20 m east, Hole U1368D was spudded at 1000 h and advanced with the APC system for two cores to 15.0 mbsf with a 15.04 m recovery (100.3%). Seafloor was established at 3750 mbrf. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. The drill string was tripped to just above the mudline, clearing the seafloor at 1135 h and ending Hole U1368D.

Hole U1368E

Hole U1368E began at 1135 h on 13 November when the APC assembly cleared the seafloor after completing Hole U1368D. The vessel was offset 20 m east of Hole U1368D. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1368E was spudded at 1210 h. Seafloor depth was established with a mudline core at 3751.9 mbrf. The APC system was used to take two cores to 10.6 mbsf with a 10.58 m recovery (99.8%). PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. The drill string was tripped to the surface, clearing the rotary table at 2000 h on 13 November and ending Hole U1368E.

Hole U1368F

After a 20 m offset to the south, Hole U1368F began on 13 November at 2000 h when the bit cleared the rotary table after tripping out of Hole U1368E. The BHA was set back, the APC bit was removed, and the rotary core bit and rotary coring system were assembled in preparation for running the new RCB BHA. The BHA was run into the hole, followed by the drill pipe. After reaching 3741 mbrf, the top drive was picked up and the drill string was spaced out to spud Hole U1368F. Water depth was recorded at 3751.9 mbrf using an offset depth from Hole U1368E. Rotary coring began at the seafloor when Hole U1368F was spudded at 0520 h on 14 November. Core 329-U1368F-2R crossed the sediment/basalt interface at 11.8 mbsf. RCB coring continued from 11.8 to 115.1 mbsf with average recovery. A total of 14 cores were taken. A total of 115.1 m were cored with a recovery of 31.74 m of core. RCB system recovery for Hole U1368F was 27.6%. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. Microspheres were also deployed on all RCB cores after Core 2R. After reaching a total depth of 115.1 mbsf, the center bit was deployed and the hole was conditioned for logging. The mechanical bit release was activated, dropping the RCB bit at the bottom of the hole. The drill string, minus the bottom half of the mechanical bit release and RCB bit, was tripped to ~30 mbsf and the logging tools were rigged up and deployed. Four logging runs, two with the triple combination (triple combo) and two with the Formation MicroScanner (FMS) tool string (no sonic) were performed successfully. At the end of logging activities, the tools were rigged down and the drill string was tripped back to the rig floor and secured for the 1073 nmi transit to the next site, ending Hole U1368F and Site U1368 at 1233 h on 18 November.

Transit to Site U1369

After an 98.1 h transit from Site U1368, covering 1073 nmi and averaging 10.9 kt, the speed was reduced and thrusters were lowered. Dynamic positioning was initiated over Site U1369 at 1454 h on 22 November 2010. The position reference was a combination of GPS signals. No acoustic beacon was deployed, but a beacon remained on standby in the event of a loss of GPS satellite coverage. Whereas automatic input into the dynamic positioning system was not possible because of a system malfunction, it was possible to manually hold the vessel in position to clear the seafloor with the BHA if necessary.

Site U1369

Five holes were drilled or cored at Site U1369. The first hole was a washdown hole drilled with the center bit in order to establish the sediment depth of 12.2 mbsf. The next four holes were cored with the APC system. The APCT-3 was not deployed because of the shallow sediment depth. PFT was pumped for the entire drilling/coring interval until the last core was on deck. APC system recovery for Site U1369 was 108%. A total of 10 cores were attempted while coring 46.1 m. The total length of core recovered at this site was 49.81 m (108.0% recovery).

Hole U1369A

Rig floor operations commenced at 1445 h on 22 November 2010. The trip to the seafloor was uneventful. The top drive was picked up and the drill string was spaced out and spudded at 0040 h on 23 November. The PFT pump was turned on to displace the drill string with the contamination testing fluid. The washdown hole was drilled to determine depth of basement. Mud line was established at 5290.5 mbrf by tagging with the bit. After drilling down, basement was established at 12.2 mbsf. The bit was pulled back above the seafloor, clearing the seafloor at 0125 h and ending Hole U1369A.

Hole U1369B

After clearing the seafloor, the center bit was pulled by wireline, the vessel was offset 20 m west, and the drill string was spaced out to spud Hole U1369B. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1369B was spudded at 0350 h on 23 November. Seafloor depth was established at 5286.3 mbrf with a mudline core. APC coring continued to 15.9 mbsf. An XCB core barrel was dropped after an initial analysis from the science party based on concern that the deepest material recovered might not have been igneous in origin. Subsequent analysis verified the rock samples to be igneous in origin and the core barrel was pulled without advancing. Three cores were taken with a total recovery of 18.14 m (114.1%). After Core 329-U1369B-3H, the bit was tripped back to just above the seafloor, ending Hole U1369B at 1030 h. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing.

Hole U1369C

Hole U1369C began at 1030 h when the APC assembly cleared the seafloor after completing Hole U1369B. After offsetting the vessel 20 m north, Hole U1369C was spudded at 1135 h and advanced with the APC system to 14.6 mbsf before encountering basement. Seafloor was established at 5288.0 mbrf. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. Three cores were taken with a total recovery of 16.1 m (110.3%). The drill string was tripped to just above the mudline, clearing the seafloor at 1530 h on 23 November and ending Hole U1369C.

Hole U1369D

Hole U1369D began at 1530 h when the APC assembly cleared the seafloor after completing Hole U1369C. After offsetting the vessel 20 m east, Hole U1369D was spudded at 1615 h on 23 November. The core liner was shattered and even though the core barrel extended 9.5 m, manganese nodules in the core catcher comprised the only material recovered. Hole U1369D was abandoned. Seafloor was established at 5288.0 mbrf using an offset from the previous hole. Recovery was limited to a 0.08 m core length and the advance was recorded as 0.1 m. Percentage of recovery is recorded as 80%. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. The hole ended at 1615 h with the mudline shot.

Hole U1369E

Hole U1369E began at 1615 h on 23 November after the failed mudline core on Hole U1369D. The vessel was offset 20 m east of Hole U1369D. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1369E was spudded at 1745 h. Seafloor depth was established with a mudline core at 5288.8 mbrf. The APC system was used to take three cores to 15.5 mbsf with a 15.49 m recovery (99.9%). PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. The drill string was tripped to the surface, clearing the rotary table at 0645 h on 24 November. The rig floor and secured for the 625 nmi transit to the next site, ending Hole U1369F and Site U1369 at 0730 h on 24 November.

Transit to Site U1370

After a 56.5 h transit from Site U1369, covering 625 nmi and averaging 11.1 kt, the speed was reduced and thrusters were lowered. Dynamic positioning was initiated over Site U1370 at 1602 h on 26 November 2010. The position reference was a combination of GPS signals. No acoustic beacon was deployed, but a beacon remained on standby in the event of a loss of GPS satellite coverage. While automatic input into the dynamic positioning system was not possible because of a system malfunction, it was possible to manually hold the vessel in position to clear the seafloor with the BHA if necessary.

Site U1370

Six holes were drilled or cored at Site U1370. The first hole was a washdown hole drilled with the center bit in order to establish the sediment depth of 66.7 mbsf and any hard layers (chert) throughout the formation. Hole U1370B had one mudline core taken before coring problems forced abandonment of the hole. Hole U1370C was drilled to 7.8 mbsf, and the attempt to take a piston core failed. The last three holes were cored successfully with the APC system. The APCT-3 was deployed four times on Holes U1370D and U1370E. PFT for contamination testing was pumped from Hole U1370C onward until the last core was on deck. A total of 26 cores were attempted while coring 206.3 m. The total length of core recovered at this site was 214.59 m. The overall recovery for Site U1370 using the APC coring system was 104%.

Hole U1370A

Rig floor operations commenced at 1602 h on 26 November 2010. The trip to the seafloor was uneventful. The top drive was picked up, the drill string was spaced out, and the hole was spudded at 0230 h on 27 November. The washdown hole was drilled to determine depth of basement. Mudline was established as 5085.7 mbrf using an offset depth from Hole U1370B. After drilling down, basement was established at 5150.4 mbrf (64.7 mbsf). Basement depth was verified by drilling two additional meters into the basement. The bit was pulled back above the seafloor, clearing the seafloor at 0620 h and ending Hole U1370A.

Hole U1370B

After clearing the seafloor, the center bit was pulled by wireline, the vessel was offset 20 m west, and the drill string was spaced out to spud Hole U1370B. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1370B was spudded at 0745 h on 27 November. Seafloor depth was established at 5085.7 mbrf with a mudline core. APC coring was terminated after the second core attempt. It appeared as if there was something blocking the seal-bore collar that was preventing the core barrel from seating. The center bit was deployed in order to verify a clean seal-bore assembly and to check flow against the slow circulating rates taken at the start of the hole. Subsequent problems determined that it was most likely the shear pins failing during the deployment of the core barrel. The hole was terminated and several remedial measures were implemented. One core was taken with a total recovery of 7.81 m (100.1%). After Core 329-U1370B-1H was recovered, the bit was tripped back to just above the sea floor, ending Hole U1370B at 1000 h on 27 November.

Hole U1370C

Hole U1370C began at 1000 h when the APC assembly cleared the seafloor after completing Hole U1370B. After offsetting the vessel 20 m north, an attempt to spud Hole U1370C was made. After multiple wireline runs and multiple attempts to spud Hole U1370C, the hole was spudded at 1810 h in an attempt to advance the hole and coring began. During the effort to continue coring, several remediation efforts were attempted. The root problem seemed to be shear pin failure during the wireline trip into the hole. Rig instrumentation indicated that the core line received increasingly high tension variation as the core line was run to greater depth. Variations were ~2500 lb of force. An extra shear pin was added to the system in an effort to land the core barrel with the shear pin assembly intact. This still failed. A 90° heading change was made to try to reduce the overall heave of the vessel. Decreasing weather and the heading change successfully reduced the heave by over a meter. In an attempt to dampen the tension variation, the compensator was opened for core barrel deployment. After a drilled advance of 7.8 m, the core barrel was finally deployed without the shear pin failure that had been experienced all day. With three shear pins installed and the core barrel landed, the mud pump pressure was insufficient to shear the pins and shoot the APC core barrel. Consequently, the core barrel was pulled to the surface and redressed with new shear system components and two shear pins. Hole U1370C was abandoned and the bit cleared the seafloor at 2000 h on 27 November, ending Hole U1370C.

Hole U1370D

Hole U1370D began at 2000 h, when the APC assembly cleared the seafloor after completing Hole U1370C. After offsetting the vessel 20 m east, Hole U1370D was spudded at 2115 h on 27 November. Seafloor depth was established with a mudline core at 5084.7 mbrf. An APCT-3 measurement was taken on Core 329-U1370D-4H. The APC coring system was used to take eight cores to 68.2 mbsf with 70.26 m recovery (103%). After Core 8H, the bit was advanced and rotated into basement to verify basement depth (68.2 mbsf) and the bit was tripped back to just above the seafloor ending Hole U1370D at 1250 h on 28 November.

Hole U1370E

Hole U1370E began at 1250 h when the APC assembly cleared the seafloor after completing Hole U1370D. After offsetting the vessel 20 m east, Hole U1370E was spudded at 1445 h on 28 November. Seafloor depth was established with a mudline core at 5085.3 mbrf. An APCT-3 measurement was taken on Cores 329-U1370E-3H, 5H, and 6H. The APC system was used to take nine cores to 65.6 mbsf with a 70.2 m recovery (107%). PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. After Core 9H, the bit was advanced and rotated into basement to verify basement depth (65.6 mbsf) and the bit was tripped back to just above the seafloor, ending Hole U1370E at 0855 h on 29 November.

Hole U1370F

Hole U1370F began at 0855 h when the APC assembly cleared the seafloor after completing Hole U1370E. The vessel was offset 20 m south of Hole U1370E. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1370F was spudded at 1010 h. Seafloor depth was established with a mudline core at 5084.8 mbrf. The APC system was used to take eight cores to 64.7 mbsf with a 66.32 m recovery (102.5%). PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. After Core 329-U1370F-8H, the bit was advanced and rotated into basement to verify basement depth (64.7 mbsf). The drill string was tripped to the surface, clearing the rotary table at 0530 h on 30 November. The rig floor was secured for the 499 nmi transit to the next site, ending Hole U1370F and Site U1370 at 0600 h.

Transit to Site U1371

After a 51 h transit from Site U1370, covering 499 nmi and averaging 9.8 kt, the speed was reduced and thrusters were lowered. Dynamic positioning was initiated over Site U1371 at 0907 h on 2 December 2010. The position reference was a combination of GPS signals. No acoustic beacon was deployed, but a beacon remained on standby in the event of a loss of GPS satellite coverage. Whereas automatic input into the dynamic positioning system was not possible because of a system malfunction, it was possible to manually hold the vessel in position to clear the sea floor with the BHA if necessary.

Site U1371

Eight holes were drilled or cored at Site U1371. The first hole was a washdown hole drilled with the center bit in order to establish the sediment depth of 122.5 mbsf. The entire time on site was plagued by high vessel heave, which hindered the APC coring. The first APC hole at the site came back with a disturbed mudline core and was abandoned. The second attempt at a mudline resulted in an over penetration without securing mudline and was abandoned as well. The following three APC holes were successfully cored to refusal. With the remaining time, an additional two holes were cored for mudline cores. The APCT-3 was deployed five times on Hole U1371D. PFT was pumped from Hole U1371E onward until the last core was on deck. APC system recovery for Site U1371 was 94.9%. A total of 46 cores were attempted while coring 410.0 m. The total length of core recovered at Site U1370 was 389.01 m (94.9% recovery).

Hole U1371A

Rig floor operations commenced at 0907 h on 2 December 2010. The trip to the seafloor was uneventful. The top drive was picked up, the drill string was spaced out, and the hole was spudded at 1845 h on 2 December. The washdown hole was drilled to determine depth of basement. Mudline was established as 5316.0 mbrf using the drill bit–tagged depth. There were no anomalies detected during the washdown to basement. After drilling down, basement was established at 5438.5 mbrf (122.5 mbsf). Total depth of the hole was 5439.5 mbrf after the bit was advanced into basement to verify basement contact. The bit was pulled back above the seafloor, clearing the seafloor at 2350 h on 2 December and ending Hole U1371A.

Hole U1371B

After clearing the seafloor, the center bit was pulled by wireline, the vessel was offset 20 m west, and the drill string was spaced out to spud Hole U1371B. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and fired from 5310 mbrf. The core barrel came back empty and the bit was repositioned to 5315 mbrf. Hole U1371B was spudded at 0300 h on 3 December. Seafloor depth was established at 5316.4 mbrf (5305.1 mbsl) with a mudline core. Vessel heave during spud in was ~4 m. The first mudline core was too disturbed for science and the hole was terminated. One core was taken with a total recovery of 8.15 m for an overall recovery in Hole U1371B of 100.6%. After Core 329-U1371B-1H, the vessel was moved 20 m north, ending Hole U1371B at 0300 h on 3 December.

Hole U1371C

Hole U1371C began at 0300 h after abandoning Hole U1371B. After offsetting the vessel 20 m north, Hole U1371C spudded at 0445 h. Core 329-U1371C-1H came back with a full core barrel and no obvious mudline. Shoot depth was 5312 mbrf, which was 3 m higher than the shoot depth for Hole U1371B. The best explanation for another mudline failure was the high heave (>4 m) at the time of spudding. One core was taken in Hole U1371C, with a total recovery of 9.85 m (103.5%). Hole U1371C was abandoned after the first core and the vessel was moved 20 m east on 3 December, ending Hole U1371C at 0445 h.

Hole U1371D

Hole U1371D was spudded 20 m east of Hole U1371C at 0635 h on 3 December. Seafloor depth was established with a mudline core at 5311.1 mbrf (5299.9 mbsl). Orientation with the Flexit tools was done on Cores 329-U1371D-1H through 11H. APCT-3 measurements were taken on Cores 4H–6H, 8H, and 10H. All temperature measurements returned good data. While pulling Core 6H, the coring line parted at the wire rope socket and the core barrel and sinker bars fell back inside the drill pipe. The wireline was removed from the hole and reheaded at surface. The aft sinker bars were installed and a rotary core barrel was dropped to "fish" the forward sinker bars. The sinker bars were recovered by wireline, and Core 6H was recovered. Total time from the incident to resumption of coring was 5.5 h. Coring continued until refusal on Core 14H. The APC system was used to take 14 cores to 126.0 mbsf with 126.87 m recovery (100.7%). After Core 14H, the bit was advanced and rotated into basement to verify basement depth. The bit was tripped back to just above the seafloor, ending Hole U1371D at 1330 h on 4 December.

Hole U1371E

Hole U1371E began with the ship offset 20 m east of Hole U1471D. Hole U1371E was spudded at 1605 h on 4 December. Seafloor depth was established with a mudline core at 5310.2 mbrf. The APC system was used to take 14 cores to 128.2 mbsf with a 118.16 m recovery (92.2%). Nonmagnetic core barrels were used for the first 12 cores. PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. After Core 329-U1371E-14H, the bit was advanced and rotated into basement to confirm basement depth and tripped back to just above the seafloor, ending Hole U1371E at 1100 h on 4 December.

Hole U1371F

Hole U1371F was offset 20 m south of Hole U1371E. After making up the first APC core barrel, it was run to bottom on the wireline and Hole U1371F was spudded at 1205 h on 5 December. Seafloor depth was established with a mudline core at 5308.3 mbrf. The APC system was used to take 14 cores to 130.6 mbsf with a 118.44 m recovery (90.7%). PFT was mixed with the drilling fluid (sea water) and pumped on all cores for contamination testing. After Core 329-U1371F-14H, the bit was advanced and rotated into basement to verify basement depth and APC advance. The drill string was tripped to just above the seafloor, ending Hole U1371F at 0655 h on 6 December.

Hole U1371G

Hole U1371G was offset 20 m south of Hole U1371F. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1371G was spudded at 0755 h on 6 December. Seafloor depth was established with a mudline core at 5314.1 mbrf. The APC system was used to take a single core to 1.4 mbsf with a 1.37 m recovery (97.9%). PFT was mixed with the drilling fluid (sea water) and pumped on for contamination testing. After taking mudline Core 329-U1371G-1H, a second core (test Core 329-U1371G-2H) was taken for training purposes. The drill string was tripped to just above the seafloor, ending Hole U1371G at 0945 h on 6 December.

Hole U1371H

Hole U1371H was offset 20 m west of Hole U1371G. After making up the first APC core barrel, the core barrel was run to bottom on the wireline and Hole U1371H was spudded at 1030 h on 6 December. Seafloor depth was established with a mudline core at 5310.3 mbrf. The APC system was used to take a single core to 6.2 mbsf with a 6.19 m recovery (99.8%). PFT was mixed with the drilling fluid (sea water) and pumped in for contamination testing. After taking mudline Core 329-U1371H-1H, the drill string was tripped to the surface, clearing the rotary table at 2326 h on 6 December. The rig floor was secured for the 1172 nmi transit to Auckland, ending the final hole and site of Expedition 329 at 2326 h on 6 December.