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doi:10.2204/iodp.pr.317.2010 OperationsTransit to Site U1351After a 1 day transit from Wellington, New Zealand, covering 257 nmi at an average speed of 11.4 kt, the vessel was positioned over Site U1351 (proposed Site CB-03B) on 18 November 2009 at 0931 h (Universal Time Coordinated [UTC] + 13 h). The position reference was a combination of Global Positioning System (GPS) and an acoustic beacon on the seafloor, weighted heavily toward the acoustic beacon (80%). The positioning beacon (FSI BAP-547W, SN 1025, 14.0 kHz, 200 dB) was deployed at 1030 h. Site U1351
Three holes were drilled at Site U1351 (Table T1). The first two holes were cored with the APC/XCB coring systems. Total core recovery was 332 m. Average recovery rates for Site U1351 were 87% with the APC coring system, 23% with the XCB coring system, and 31% for all cores. Hole U1351B was logged with limited success. The third hole was drilled with a 9 Hole U1351ARig floor operations commenced at 0931 h on 18 November. The drill string was spaced out, placing the bit at 126.5 m drilling depth below rig floor (DRF) or 4.9 m above the "corrected" precision depth recorder (PDR) depth of 131.4 m DRF. The first APC barrel recovered ~2.7 m of core, and an official seafloor depth was established at 133.3 m DRF. APC coring continued through Core 317-U1351A-6H to 28 m DSF using standard steel coring assemblies. All cores after Core 317-U1351A-2H were partial-stroke cores, indicating very firm near-surface sediments. The hole was terminated after Core 317-U1351A-6H. Contamination testing was done on all cores with perfluorocarbon tracers (PFT) and microspheres. A temperature measurement was taken with the APCT-3 at Core 317-U1351A-4H. Average recovery for Hole U1351A using the APC coring system was 97.6%. The drill string was pulled back to the seafloor and the bit cleared the seabed at 2330 h on 18 November. Hole U1351BHole U1351B officially began at 2330 h on 18 November. The vessel was offset 20 m south of Hole U1351A, and coring in Hole U1351B began at 0045 h on 19 November. Hole U1351B was piston cored to 94.7 m DSF with a total recovery of 81.12 m (81%). Orientation was measured on the first five cores, but poor APC coring conditions forced the tool to be removed after this point. The XCB system was deployed for most of the remaining interval, Cores 317-U1351B-14X through 116X (94.7–1030.6 m DSF). Recovery was acceptable (ranging from 20% to 100%) from the top of the XCB interval to ~429 m DSF, where it dropped to nearly zero for seven cores. We switched back to the APC system three times (Cores 317-U1351B-57H through 59H, 65H, and 78H) in an attempt to get better recovery. However, penetration was short each time (0.8–4 m; recovery was nominally high but was based on recovered length) and XCB coring was resumed. The average core recovery for all XCB cores was 23%. Coring was terminated at 1030.6 m DSF after the XCB core barrel became stuck inside the bottom-hole assembly (BHA). After the core barrel was freed, we stopped coring to log Hole U1351B. A 50 bbl high-viscosity mud sweep was pumped to clean the hole, and the hole was displaced with 420 bbl of 9.0 ppg mud with a 100+ Marsh funnel viscosity. The drill string was tripped back to 80 m DSF, and the triple combo was rigged up and run to the bottom of the hole. Hole conditions prior to logging were good, but the gauge of the hole was largely unknown. The first logging run revealed a hole that was oversized over most of its length. Next, the FMS-sonic tool was rigged up and deployed. The tool failed to pass 618 m wireline log depth below rig floor (WRF), indicating that the hole was collapsed and bridged near that depth. The hole was logged from that point upward. A 12 bbl cement plug was pumped according to IODP policies for drilling on a continental shelf, with the string at 283 m DSF. The drill string was tripped back to the surface, and the bit cleared the rotary table at 1800 h on 25 November, ending Hole U1351B. Contamination testing for microbiology was done every ~50 m in Hole U1351B. Both PFTs and microspheres were deployed. Temperature measurements were taken with the APCT-3 tool at Cores 317-U1351B-10H and 12H and with the SET tool at Cores 317-U1351B-16X and 42X, with mostly poor results. Average core recovery in Hole U1351B was 84% for the APC system and 23% for the XCB system. Total recovery for Hole U1351B was 304.5 m out of a cored interval of 1030.6 m (30%). Hole U1351C
The objective of Hole U1351C was to provide a fresh, dedicated hole for wireline logging without coring, and operations officially began at 1800 h on 25 November. The ship was offset 30 m south of Hole U1351B. A new BHA was made up with a 9 At 1915 h on 27 November, while the hole was being swept clean with mud in preparation for logging, a sudden wind change forced the vessel outside its maximum positioning offset (8% of water depth, or ~10 m). The vessel lost power to three of the six forward thrusters while trying to respond to the sudden shift. Position and power were reestablished within 15 min. The maximum excursion from the hole was 38 m. With all drilling parameters still normal, Hole U1351C was displaced with logging mud in preparation for logging. The drill string was tripped to 80 m DSF, and the section of drill pipe that was located at the seabed during the excursion was inspected after it was recovered at the surface. No damage to the drill string was visible. The triple combo logging string was assembled and run into Hole U1351C. The winch lost weight with the tool at ~912 m WSF, indicating that the tool was stuck. At that point the tool could not be moved up or down. We decided to cut the logging line and trip in with drill pipe over the logging line in an attempt to recover the triple combo logging string. The logging tools were eventually recovered after tripping over the wireline from 80 to 708 m DRF. The tools were pulled up into the drill string, and the logging line was pulled up onto the rig floor using T-bars until sufficient length was recovered to attach the line to the coring winch. After the line was spooled onto the coring winch, the coring winch was used to recover the logging tools. The logging tools were set back on the rig floor, the drill string was pulled back to ~285 m DRF, and the hole was cemented with 10 bbl of 14 ppg cement. The drill string was then tripped back to the rig floor and secured for the 8 nmi transit to the next site, ending Hole U1351C at 0200 h on 30 November. Transit to Site U1352After a 3 h, 8 nmi move from Site U1351 in dynamic positioning mode, the vessel was positioned at Site U1352 (proposed Site CB-04B) at 0500 h (UTC + 13 h) on 30 November. The position reference was a combination of GPS and an acoustic beacon on the seafloor, weighted heavily toward the acoustic beacon (80%). The positioning beacon (FSI BAP-547W, SN 1025, 14.0 kHz, 200 dB) was deployed at 0455 h on 30 November. Water depth at the new site was 354.4 m DRF based on the PDR. Site U1352Four holes were drilled at Site U1352 (Table T1). The first hole was cored with the APC system to 42.2 m DSF with the objective of providing whole-round samples for microbiology, chemistry, and geotechnical studies. The second hole was cored with the APC/XCB coring systems to XCB refusal at 830.9 m DSF. The third hole was drilled and cored with the RCB coring system to the target, record depth of 1927.5 m DSF. The fourth hole was cored with the APC system to 127 m DSF while we waited for the weather to improve before transit to the next site. Logging was attempted with partial success in Holes U1352B and U1352C. The APCT-3 temperature tool was deployed five times with good results. Overall recovery for Site U1352 was 102% with the APC, 59% with the XCB, and 51% with the RCB. The total cored interval for Site U1352 was 2296.5 m, and total recovery was 1444.1 m (63%). Rig floor operations commenced at 0500 h on 30 November when the vessel shifted to dynamic positioning control and ended at 2100 h on 21 December when the vessel was secured for transit. Hole U1352AThe BHA was made up with an APC/XCB bit, and coring in Hole U1352A began at 1145 h on 30 November. The mudline was established at 354.8 m DRF. APC coring continued through Core 317-U1352A-5H (42.2 m DSF) using nonmagnetic coring assemblies. Core orientation was measured on all cores, and a temperature measurement was taken with Core 317-U1352A-4H. Contamination testing was done on all cores with PFTs and microspheres. A total of 43.9 m of core was recovered in Hole U1352A (104%). The drill string was pulled back to the seafloor, and the bit cleared the seabed at 1530 h on 30 November, officially ending operations in Hole U1352A. Hole U1352BThe vessel was offset 20 m south of Hole U1352A, and Hole U1352B was piston cored to Core 317-U1352B-36H at 297.0 m DSF with a total recovery of 299.3 m (101%). Core orientation was measured on the first 17 cores before the FlexIt tool was pulled up because of severe piston coring conditions. The XCB coring system was deployed for Cores 317-U1352B-37X through 94X (297.0–830.9 m DSF). Recovery for the XCB system was very good to ~500 m DSF. Below that depth a steadily increasing number of cores had poor recovery. A total of 533.9 m was cored, and 315.0 m was recovered (59%). Toward the bottom of the hole, the XCB cutting shoe began to overheat and the formation caused excessive torque. The risk of damaging the core barrel was too high to continue with the XCB system. A 50 bbl high-viscosity mud sweep was pumped to clean the hole. The drilling string was tripped back to 80 m DSF, and the triple combo tool string was rigged up and run into the hole. The first logging run failed to pass 487 m WSF because the hole evidently collapsed during logging preparations. Two passes were successfully recorded. The caliper readings indicated excessive borehole size that would not permit an adequate clamp for the Versatile Seismic Imager (VSI) tool to obtain reliable data, and the VSP plan was canceled. The FMS-sonic tool string was subsequently deployed, and it also encountered a borehole obstruction somewhat higher in the hole. FMS-sonic logs were recorded from 442 m WSF. After the logging tools were rigged down, a 12 bbl cement plug was pumped at 154.4 m DSF. The drill string was tripped back to surface and cleared the rotary table at 1615 h on 5 December, ending operations in Hole U1352B. PFTs and microspheres were deployed every ~50 m in Hole U1352B for microbiological contamination testing. Temperature measurements with the APCT-3 tool were taken with Cores 317-U1352B-6H, 10H, 15H, and 20H. All temperature measurements had good decay curves. The cored interval in Hole U1352B was 830.9 m, and total recovery was 614.3 m (74%). Hole U1352CThe ship was offset 20 m south of Hole U1352B and operations at Hole U1352C began with the makeup of a new BHA for the RCB system, which was fitted with a mechanical bit release to facilitate logging after coring was complete. Coring in Hole U1352C began at 2015 h with a center bit installed. At ~300 m DSF the center bit was recovered, inspected, and reinstalled. The hole was further advanced to 574.7 m DSF, where the center bit was pulled up again and a rotary core barrel was dropped. The hole was cored with the RCB system from 574.7 to 603.6 m DSF (Cores 317-U1352C-2R through 4R) and recovered 12.79 m of core (44%). The center bit was reinstalled, and drilling continued to 660.0 m DSF. The center bit was again pulled up, and rotary coring resumed for Cores 317-U1352C-6R through 41R (660.0–1009.9 m DSF). Sweeps of 20 bbl high-viscosity mud were performed every 50 m of coring to clean the cuttings from the hole. At 1900 h on 8 December, a 50 bbl sweep was pumped, and a wiper trip of the drill string was made from ~200 to 1007 m DSF and back. Coring resumed ~8 h later for Cores 317-U1352C-42R through 118R (1009.9–1661.5 m DSF), with sections of good and poor recovery. The deplugger was run, and coring intervals were reduced to 5 m several times in an attempt to improve core recovery. On 15 December at 2030 h, a 50 bbl sweep was pumped, a wiper trip of the drill string was made from ~1000 to 1662 m DSF and back, and coring resumed ~7 h later. The interval of regular 20 bbl hole cleaning mud sweeps was decreased to 40 m. On 17 December, it became evident that the Marshall Paraconformity, the scientific target of the hole, was deeper than anticipated. Permission was requested and received to exceed the original EPSP limit of 1913 m DSF by up to 250 m (to 2163 m DSF). The Marshall Paraconformity was recovered in Core 317-U1352C-140R (1851–1861 m DSF) on 18 December. Coring continued to Core 317-U1352C-148R (1927.5 m DSF) in order to provide sufficient depth to log across the Marshall Paraconformity. At 1740 h on 19 December, the last core from Hole U1352C was received on deck. Starting at 796 m DSF, PFTs and microspheres were deployed at ~50 m intervals throughout Hole U1352C for microbiological contamination testing. The 1928 m penetration depth of Hole U1352C established a new single-bit, single-expedition record for the JOIDES Resolution and is the deepest sediment hole ever drilled by IODP or its predecessor programs. The cored interval in Hole U1352C was 1296.4 m, and 655.0 m of core was recovered (51%). The hole was swept clean with a 50 bbl sweep of high-viscosity mud, the RCB coring bit was released, and the drill string was tripped out to ~900 m DSF. The top drive was picked back up, and 400 bbl of high-viscosity logging mud was displaced into Hole U1352C. The top drive was set back, and an attempt was made to continue the trip out of the hole. After one stand, excessive drag required the top drive to be reinstalled, and the trip out of the hole continued with rotation until the end of the string reached 545 m DRF. The top drive was then set back, and the drill string was pulled back to 439 m DRF. The upper guide horn was removed, and the vibration-isolated television (VIT) camera was deployed to observe and document the cone of cuttings at the seafloor while logging. The drill string was set to a logging depth of 458 m DRF. The logging string was rigged up to run a modified version of the triple combo. The first logging run indicated that the hole had collapsed, and the tool string was unable to pass 562 m WRF. The tool string was pulled back to the surface and rigged down. The drill string was tripped back to the surface and cleared the rotary table at 2200 h on 20 December, ending Hole U1352C. Hole U1352DWhen operations in Hole U1352C concluded, the winds and swells were too high for operations to begin at the next site, which was in extremely shallow (<100 m) water. In anticipation of a weather delay of ~24 h, we decided to core Hole U1352D first. An APC/XCB assembly was made up, and piston coring in Hole U1352D began at 0615 h on 21 December and continued through Core 317-U1352D-14H (0–127.0 m DSF). Core recovery totaled 130.8 m (103%). Nonmagnetic coring assemblies were used, and core orientation was measured on all cores. The drill string was pulled back to the rotary table, the BHA was racked back, and the rig floor was secured for transit at 2100 h on 21 December, ending Hole U1352D and Site U1352. Transit to Site U1353After an 18 nmi transit from Site U1352, the vessel was positioned over Site U1353 (proposed Site CB-01A) at 2320 h (UTC + 13 h) on 21 December. Water depth was estimated at 96.4 m DRF based on the PDR. The position reference was a combination of GPS and an acoustic beacon on the seafloor, weighted heavily toward the acoustic beacon (80%). At 2346 h on 21 December, the positioning beacon (FSI BAP-547W, SN 1025, 14.0 kHz, 200 dB) was deployed. Site U1353Three holes were cored or drilled at Site U1353 (Table T1). The first hole was cored with the APC system to 56 m DSF to provide sufficient samples for microbiology, chemistry, and geotechnical studies. The second hole was cored with the APC/XCB coring systems to the target depth of 614 m DSF. The third hole was drilled to 529 m DSF as a dedicated logging hole with a center bit installed in the APC/XCB BHA. Hole U1353A has the shallowest water depth of any hole drilled by the JOIDES Resolution for science. The only holes on record that are shallower and that were cored by the JOIDES Resolution were done at the Eniwetok Lagoon on Leg 143. Holes 870A/B were cored from 48.7–49.8 m DSF with a total recovery for both holes of 0.6 m. Both holes were drilled to test the dynamic positioning system and were not drilled for scientific objectives. Core recovery at Site U1353 was 100% for the APC system and 5% for the XCB system. The total cored interval for Site U1353 was 670.3 m with 267.86 m (40%) of recovered core samples. Hole U1353ARig floor operations commenced at 2320 h on 21 December when the vessel shifted to automatic dynamic positioning control. The BHA was made up with an APC/XCB bit, and operations in Hole U1353A began at 0230 h on 21 December. APC coring continued through Core 317-U1353A-8H to 56.0 m DSF using nonmagnetic coring assemblies. Orientation was taken on the first six cores. The APCT-3 temperature tool was deployed once (Core 317-U1353A-5H) without success. The type of formation encountered proved too difficult for our temperature measurement tools. Contamination testing was done on all cores with microspheres. Overall recovery for Hole U1353A was 56.38 m over an interval of 56 m (101%). The drill string was pulled back to the seafloor, and the bit cleared the seabed at 1115 h on 22 December. Hole U1353BThe vessel was offset 20 m south of Hole U1353A, and coring in Hole U1353B began at 1215 h on 22 December. Hole U1353B was piston cored to 80.2 m DSF with a total recovery of 80.74 m (101%). Because of the rough piston coring conditions encountered in Hole U1353A, orientation and temperature measurement tools were not deployed in this hole. In an effort to maximize recovery and make progress in the hole, the XCB coring system was deployed intermittently from Cores 317-U1353B-14X through 60H (80.2–257.7 m DSF). In this interval, 9 XCB deployments cored 69.7 m and recovered 2.53 m of core (4%), and 38 APC deployments cored 107.8 m and recovered 107.6 (100%). The superior recovery with the APC was not without penalty. Almost all of the piston cores were partial strokes (average = 3.7 m), and because the bit was advanced by recovery, the rate of penetration was very slow. Many cores had shattered core liners, and the piston seals and core catchers were damaged. In addition, the recovered material included a large amount (>50%) of reworked or fallen in material. Below 257.7 m DSF, Cores 317-U1353B-61X through 98X were taken to a total depth of 614.3 m DSF, recovering 20.55 m (6%). The drill string was tripped back to 250 m DRF, and a 12 bbl, 14 ppg cement plug was pumped according to IODP policies for drilling on a continental shelf. The drill string was tripped back to just above the seafloor, and the bit cleared the seafloor at 2050 h on 26 December, ending Hole U1353B. A total of 211.48 m of core was recovered over an interval of 614.3 m (34%). Hole U1353CThe ship was offset 20 m north of Hole U1353A, and drilling in Hole U1353C, the dedicated logging hole, began at 2230 h on 26 December. The hole was drilled to 529 m DSF, swept clean with a 50 bbl high-viscosity mud sweep, and displaced with 300 bbl of high-viscosity 10.5 ppg mud. The drill string was tripped out of the hole to 202 m DRF. The triple combo logging tool string was rigged up without nuclear sources (neutron porosity and gamma ray density) to minimize operational risk. The tool string was run into the hole, tagging the bottom at 621 m WRF. The hole was logged up from there. The logging string was pulled to the surface, rigged down, and the FMS-sonic tool string was assembled and run into the hole to 343 m WRF, where an obstruction was encountered. The hole was logged up from 343 m WRF. A second attempt was made to run down with the FMS-sonic tool string, but the string was only able to reach ~300 m WRF. Hole conditions during logging continued to deteriorate until the hole collapsed completely just below 202 m WRF. After the drillers worked to free both the drill string and the logging string, the logging string partially reentered the drill string. The drill string and the logging line were pulled up onto the rig floor using T-bars from ~200 m DRF. This hole could not be cemented with the logging tools stuck in the drill string, and the hole completely collapsed as the BHA was pulled clear of the hole, making the hole impossible to cement. The logging tools were rigged down on the rig floor. The BHA was broken down and secured at 2100 h on 28 December, ending Hole U1353C and operations at Site U1353. Transit to Site U1354After a 7 nmi transit from Site U1353, the vessel was positioned over Site U1354 (proposed Site CB-02A) at 2320 h (UTC + 13 h) on 28 December. Water depth at the new site was estimated at 120.4 m DRF using the PDR. The position reference was a combination of GPS and an acoustic beacon on the seafloor, weighted heavily toward the acoustic beacon (80%). At 0001 h on 29 December, the positioning beacon (FSI BAP-547W, SN 1025, 14.0 kHz, 200 dB) was deployed. Site U1354Three holes were cored with the APC/XCB coring systems at Site U1354 (Table T1). The third hole was drilled with a center bit installed to 65 m DSF to advance the hole after severe weather ended Hole U1354B. Logging of Hole U1354C was successfully completed with a special tool configuration that combined the NGR tool, the sonic tool, and the resistivity tool. The SET temperature tool was deployed twice without success. The type of formation encountered proved too difficult for our temperature measurement tools. Overall recovery for Site U1354 was 100% with the APC coring system and 39% with the XCB system. The total cored interval for Site U1354 was 479.8 m with 294.50 m (61%) of recovery. Hole U1354ARig floor operations commenced at 2345 h on 28 December when the vessel stabilized over Hole U1354A. Coring in Hole U1354A began at 0415 h on 29 December with 3.8 m of mudline core, establishing the seafloor at 121.2 m DRF and the water depth at 109.8 m. APC coring continued through Core 317-U1354A-19H to 85.4 m DSF using nonmagnetic coring assemblies. A 2 m section (64.9–66.9 m DSF) had to be drilled to advance through a section of shells and shell fragments. Core orientation was measured on the first three cores, but hard formation and incomplete piston strokes prompted a decision to remove the tool. Temperature measurements were not attempted on this hole because hole conditions were poor and waiting for 10 min without circulation in shallow water was deemed too risky. Overall recovery for Hole U1354A using the APC coring system was 100%. The drill string was pulled back to the seafloor, and the bit cleared the seabed at 2300 h on 29 December, officially ending the hole. Hole U1354BThe vessel was offset 20 m south of Hole U1354A, and coring in Hole U1354B began at 2330 h on 29 December. Hole U1354B was piston cored to 77.2 m DSF with a total recovery of 77.52 m (100%). Because of the rough piston coring conditions encountered in Hole U1354A, the core orientation and downhole temperature tools were not deployed. Coring was terminated at 77.2 m DSF after 15 APC cores were taken, because highly variable winds from the south caused positioning problems. The vessel could not maintain its position in the required watch circle, so we decided to wait for the weather to improve. The drill string was tripped back to just above the seafloor, and the bit cleared the seafloor at 1245 h on 30 December, ending Hole U1353B. Hole U1354CHole U1354C officially began at 0700 h on 31 December when the vessel was again able to maintain its watch circle over the new location. The ship was offset 20 m south of Hole U1354B, and coring began at 0715 h on 31 December. The hole was drilled to 65 m DSF with the center bit installed before two APC cores were taken. The core liner shattered on the second attempt, and the APC system was replaced with the XCB system to core through a particularly dense layer of shells. Core recovery with the XCB was initially very good but deteriorated downhole. Coring with the XCB continued to 384.2 m DSF (Core 317-U1354C-36X). The total penetration for Hole U1354C was 384.2 m. The total cored interval for Hole U1354C was 319.2 m with 133.37 m of core recovered (42%). The hole was swept clean with a 50 bbl high-viscosity mud sweep and displaced with 320 bbl of high-viscosity 10.5 ppg logging mud. The drill string was tripped out of the hole to 225 m DRF (100 m DSF). A special logging string was assembled to include all basic sensors except nuclear sources into a single run. The string included resistivity (Dual Induction Tool [DIT]), sonic compressional and shear (Dipole Sonic Imager [DSI]), and natural gamma ray spectroscopy (Hostile Environment Gamma Ray Sonde [HNGS]) tools. The tool string was rigged up in the early morning of 31 December and tagged the bottom of the hole at ~505 m WRF. A short "repeat section" was recorded from there to ~440 m WRF. The tool string was returned to total depth and then recorded a main pass from total depth up to the seabed. The drill string was tripped back to 275 m DRF, and a 12 bbl, 14 ppg cement plug was pumped. At 0615 h on 31 December, the logging tools were rigged down. The drill string was then tripped to the surface and the BHA was broken down and secured for transit. After the beacons were recovered and the rig was secured for transit, operations at Hole U1354C, at Site U1354, and on Expedition 317 ended at 1200 h on 2 January 2010, and the vessel departed for the 24 h transit to Wellington, New Zealand. |
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inch tricone bit for logging purposes. Logging was attempted, but the tool became stuck and had to be recovered. The third-generation advanced piston corer temperature tool (APCT-3) was deployed three times, and the SET temperature tool was deployed twice. Data from four out of five deployments were severely compromised, probably because of sediment that had fallen to the bottom of the hole and/or motion at the bit.