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Weekly report #8

IODP NanTroSEIZE Stage 1:
Expedition 314: NanTroSEIZE LWD Transect
Weekly Report #8 (Final report)
Date 15/Nov/2007

Chikyu moved upstream by 5nm at 00:00 a.m. on 9 November and began running into the hole with MWD assembly for the pilot drilling while drifting from 04:00 a.m. Continued running drill string from 06:00 a.m. while checking every single connection which might have been loosen by the strong vibration during drilling in previous hole. Site C0006A was spudded for the pilot drilling at 00:15 a.m. on 10 November (3875 m water depth). Drilling was continued after short trip between 599.5 m and 454.5 mbsf, then tightened up lube-oil gear which had been shaken loose due to heavy vibration. Target Depth for the pilot hole at 885.5 mbsf was finally reached at 20:45 p.m. on 11 November.

Expedition 314 Shipboard members include marine crew,
drilling engineers, lab technicians and scientists.
>>Expedition 314 Photo Gallery

Drill floor equipments were checked and tighten up that was caused by heavy vibration. After pulling out the MWD tool string, ship moved 2 nm upstream. LWD assembly was made up at 11:15 a.m. on 12 November and began running into the hole while ship was drifting. At 00:45 a.m. of 13 November, seabed was confirmed at 3871.5 m water depth, spudded and jetted down to the 40 m and then began rotary drilling. Continued drilling to the 302.5 mbsf and found pressure dropping due to the lost of communication from MWD tool at 14:00 p.m. on 13 November. However drilling finally reached to the 885.5 mbsf TD at 16:45 p.m.

Science party began packing up data boxes, backing up data, and finalizing reviewed reports this week. Expedition 315 advanced scientists group embarked Chikyu on 11 November, and started working in the lab area. Meeting was held to discuss end of cruise logistics and post-cruise research plan on 11 November. Expedition 314 officially ended midnight of November 15, 2007 and science party left the Chikyu on November 16 in three helicopter flights.

The 8 weeks of report about the Expedition 314 was reported by the Co-Chief Scientists (Dr. Masataka Kinoshita and Dr. Harold Tobin), CDEX Operations Superintendent (Mr. Ikuo Sawada and Tsuyoshi Abe) and CDEX Expedition Project Manager (Moe Kyaw Thu).

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Weekly report #7

IODP NanTroSEIZE Stage 1:
Expedition 314: NanTroSEIZE LWD Transect
Weekly Report #7
Date 09/Nov/2007

After the Pilot hole assembly from Hole C0004A was back on the drill floor, preparations began for the LWD assembly at 03:45, and a shallow hole test was made at 08:00 on 2 November. While running into the hole, Chikyu moved 2 nm up current to launch the ROV and then continued running into and tag seabed at 18:00 (2637 m water depth). We spudded Hole C0004B at 18:45, jetting down to 60.5 m at first, and then began rotary drilling at 20:15. After reaching the depth of 234.5 meters below the seafloor (mbsf), a short wiper trip was carried out between 234.5 and 99.5 mbsf from 03:30 for an hour on 3 November. Drilling continued and reached the Target Depth at 400 mbsf at 12:30. LWD tools were back on drill floor at 21:45 and data was retrieved at 00:00 of 4 November. Recovering beacons from the seabed, moved to the next site. Chikyu moved 5 nm upstream at 16:12 and began drifting at 18:45 while running into the hole with a pilot hole assembly. The position of C0005A (NT2-01E) was confirmed at 00:45 of November 5, then we tagged the seabed and spudded the pilot hole at 01:00. The first 50 m was jetted in, and then rotary drilling began at 02:15. Soon after the short wiper trip was started from 524 mbsf at 17:00, overpull was observed at 486 mbsf. We tried to free and worked through the apparent pack off slowly. The pipe was reamed between 448 and 486 mbsf, and pulled out to 337 mbsf and then run back in to 450 mbsf. An attempt was made to ream to bottom and circulate at 19:30. However, the pipe became stuck at 461 mbsf at 20:15 and was freed after applying torque and work on the pipe. Unable to run in again to the previous depth, and with hole conditions worsening, a decision was made to pull out and abandon the hole at 23:00. The hole was displaced with kill mud at 385 m at 23:30, and we began pulling out at 00:00 of 6 November.

Pipes are connected on the drill floor and run into the seabed. Hole C0006A was spudded into the seafloor at a depth of 3875 m water depth at 00:15 on 10 November.
>>Expedition 314 Photo Gallery

The ship moved to the NT2-01G location 300 m to the southeast, inside the same beacon network. The trouble of hydraulic power system of ROV was found and was recovered on deck for repair. Due to bad weather and strong current of 4.5 knots, the ROV was re-launched repeatedly during the day. Chikyu drifted 3.8 nm downstream and had to move back up current slowly with the drill string hung below the vessel. Started running into the hole again from 00:00 of 7 November. After the ship moved 2 km up current at 11:15, the pilot hole assembly began running in to the hole and tagged seabed at 2524.5 m water depth at 18:00. However, a problem of hydraulic pressure of the ROV was occurred, we finally decided at 19:00 to pull out from the depth of 37 mbsf, and move to NT1-03.

Chikyu moved to the location of NT1-03, and set beacons with the ROV at 04:15 on 8 November. Deploying 5 beacons and finished at 23:00, followed by the calibration of their position. Chikyu then moved 5 nm up current and the MWD pilot hole assembly was run in while checking pipe connections of every joint. Hole C0006A was spudded into the seafloor at a depth of 3875 m water depth at 00:15 on 10 November.

Review of the Site C0003 reports began 3 November. The science party began working on processing and interpretation of LWD-MWD data from the Site C0004 (NT2-01I) starting 4 November. The science party met on 5 November to review the processed sonic data results with the data and consulting services specialist. The expedition publications schedule was also confirmed in the meeting. On 7 November, a science meeting was held to discuss the change of drilling plan was made after delays from ROV troubles. Site summary meeting for the Site C0004 was made on 8 November and science party submitted their site report on 9 November for review.

Weekly safety drill (fire and abandon ship) was held on 4 November. At Lab, continued preparation for the following coring expeditions: maintenance and instrument setup of core splitter, pycnometer, MSCL-C, ion chromatograph and titrator, SQUID, carbonate analyzer; training of Xray CT, MSCL-W, core splitter and SQUID operations and core location management system. Also carried out carrying core racks from lab to containers.

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Weekly report #6

IODP NanTroSEIZE Stage 1:
Expedition 314: NanTroSEIZE LWD Transect
Weekly Report #6
Date 02/Nov/2007

The operations to recover the dropped drill pipe and cementing continued this week. The Chikyu sailed 14 nm NNW to move away from the strong current and typhoon after the recovery assembly was pulled out of the hole at 00:00 a.m. on 27 October. At 16:00 p.m. of 27 October Chikyu sailed back to Site C0003A and a recovery assembly was made up again. After moving to the 6 nm upstream, the assembly began running into the water to about 1800 m, and ROV dived while drifting back to position. The hole was re-entered at 03:15 a.m. on 28 October, and run in to the 292.5 meter below seafloor.
After continuous attempts at recovering the disconnected section, JAMSTEC determined to abandon recovery operations on October 29th because of difficulties with the geological formation at the site and condition of the remaining disconnected pipe. At 19:00, Chikyu sailed 500 m upstream and sealed the borehole with concrete. Seawater was displaced with concrete and confirmed cement return to the seabed by ROV. After cementing, all assembly was pulled out of the hole, ROV recovered. Beginning at 16:00 p.m., beacons were picked up and Chikyu moved to the next site, NT2-01-I pilot hole location at 03:45 a.m. on 31 October and beacons were set. After making up pilot hole assembly, Chikyu drifted 4 nm upstream while running the assembly from 20:00 p.m. Position was confirmed at 04:30 a.m. and an pilot hole (2632 m water depth) was spudded at 04:45 a.m. on 1 November. It was jetted down from the seafloor to 75.5 meters below the seafloor (mbsf), and rotary drilling began. A short wiper trip was made between 222.5 to 70.5 mbsf. 400 m Target Depth was reached at 18:45 p.m. and the pilot drilling assembly pulled out of the hole.
After the pilot hole assembly was back on the drill floor, preparations began for the LWD assembly at 03:45 a.m. on 2 November.

Drill bit running through more than 2000 meters depth in water, monitored by ROV camera.
>>Expedition 314 Photo Gallery

Science party discussed the drilling plan for the remaining 3 weeks on the 26th Oct. On 27th Oct, final site summary meeting for Site C0002 was held and each group submitted their site reports on the 28th. On 29th, a science seminar was held on crustal structure in the Nankai Trough, and the science party continued working on the real-time MWD results from Hole C0003A. Site summary meeting for C0003 was held on 1 November and reports are due to be submitted on the 3rd. Continued the preparation for the coring expeditions: maintenance- cleaning microscopes; instrument setup- , X-ray CT, SQUID, canbonate analyzer, titrator and close-up photo system; and training- Xray CT operation and core rack handling. Discussion on lab measurements was made between Lab technicians and NanTroSEIZE Specialty Coordinators, working together for the preparation for the coming coring expeditions.

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Weekly report #5

IODP NanTroSEIZE Stage 1:
Expedition 314: NanTroSEIZE LWD Transect
Weekly Report #5
Date 26/Oct/2007

The week has been mixture of the happiness at the beginning after seeing great data from the C0002A and smooth drilling up to the 500 meters below seafloor (mbsf) at the C0003A, and kind of shock for disconnection of LWD assembly at the C0003A and recovering days.

Shipboard scientists examined the drill cuttings (rocks) that remained in the drill pipe
through a loupe. Sanny Saito (JAMSTEC), Harold Tobin (Univ. of Wisconsin) and
Kylara Martin (Univ. of Texas) (Left to right)
>>Expedition 314 Photo Gallery

Drilling assembly deployment for Site C0003 was done while drifting downstream at 2 knots for 12 nm from 14:00 on 19 October. On the way, an Azimuth Thruster blower motor was replaced and arrived at the site at 10:45, beacons were calibrated, the bit was positioned above the seafloor and then a first check-shot for seismic data acquisition was performed. Hole C0003A was spudded at 12:45 and jetted in 50 m. Rotary drilling began at 13:30 and drilled to more than 500 mbsf without much difficulty. At about 530 mbsf, sticky hole conditions came on relatively suddenly and drilling went to with excessive torque and rising pump pressure. The bit became stuck, and rotation was not possible though circulation continued. While trying to turn and move the pipe to free it, the lower part of drill pipe and LWD tools became disconnected at 14:15 on 21 October. Continued to attempting to recover the remaining string and LWD tools by overshot and fishing assembly many times, but it did not go successfully at this moment.

During the recovery operation, scientists processed and interpreted the LWD data taken from Site C0002A continuously. Report drafts for the Site C0001 are under the final review by co-chief Scientists and editor-in-chief. The scientific party reviewed and discussed the results at a first site summary meeting on October 24. A second, final meeting will be held on 27 October to finalize the site reports.

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Weekly report #4

IODP NanTroSEIZE Stage 1:
Expedition 314: NanTroSEIZE LWD Transect
Weekly Report #4
Date 19/Oct/2007

After finishing the diagnosis, correction, and final evaluation of the Dynamic Positioning and Acoustic Positioning Reference System (APRS), the ship moved to a low current area (14 nm northwest) in order to avoid shock and vibration from the Kuroshio current while picking up and running in with the LWD assembly and drill collars on 13 October. Drifting back to Site C0002, and Hole C0002A was spudded in at 00:45 of 14 October. The top 70.5 m was jetted in, and then rotary drilling began. Up to the depth of 562.5 meter below seafloor (mbsf), real time results showed good hole condition, little deviation from vertical, and measurement quality was also good. A short wiper trip was carried out at 709.5 mbsf for 8 stands, including a re-log of a short missed interval. Drilling continued without excessive torque or downhole pressure all the way to the planned Total Depth of 1400 m below the sea floor, reaching TD (1401.5 mbsf) at 11:15 on 17 October.
While pulling out of the hole, seismic data tool check-shot points were taken at every pipe connection to double the number of seismic tie depths. Data from all LWD tools were successfully dumped and pre-processing by field engineers is now ongoing. The seismic data had a battery failure before retrieval of the tool, and the data had to be sent to land base for pre-processing. As the assembly was rigged down, the ROV was deployed to pick up four beacons, then the ship was moved to next site (NT2-01) and four beacons were deployed at the new location.

Drilling operation on the Chikyu proceeds regardless of day or night.
>>Expedition 314 Photo Gallery

This week processing and interpretation of the LWD data taken from Site C0001C and C0001D was the main activity. The scientific party reviewed and discussed the results at a first site summary meeting on October 12. A second, final meeting was held on 15 October, to confirm results from each group as they prepared the site report. Report drafts are under review by Co-Chief Scientists since October 17.
Meanwhile, real time monitoring of data from Site C0002A was being carried out in the lab area. In a first for IODP, LWD engineers and scientists continuously updated the drilled depth on the seismic data, plotting the bit position on seismic depth sections in near-real time. The real time gamma, resistivity, and other logs indicated that the bit passed from the Kumano Basin sediments into the underlying Accretionary prism and remained in this interval until the TD at 1400 meter.
Special technical seminars were held for LWD tools shocks and vibrations by an LWD engineer on October 16, and VSP surveying and data processing on 17 October.

Co-Chief Scientist and several scientists were interviewed by telephone or email for media in their home countries. Weekly safety drill (oil spill and abandon ship) was held on October 14 and bi-weekly safety management system meeting was held on October 15.

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Weekly report #3

IODP NanTroSEIZE Stage 1:
Expedition 314: NanTroSEIZE LWD Transect
Weekly Report #3
Date 12/Oct/2007

LWD drilling continued at Hole C0001D, with inclination survey results ranging between 2.7 and 3.5 degree. Drilled to the 976 meter below seafloor (mbsf) and decided to pull out. Scientific target on this hole was achieved and decided to move next drill site because of the dynamic positioning system problem.
A DPS specialist boarded the ship on October 7 and began working on DPS troubleshooting. After pulling out from the hole and rig down of the LWD tools and Drilling assembly, the Chikyu was moved 10 km to Site NT3-01 for positioning and site survey with ROV on October 8. While extensive testing for the DPS was ongoing, additional stands of drill pipe needed for the deep water sites were picked up, a free-fall-funnel was assembled, the ROV main umbilical cable was cut and spliced, and general drill floor maintenance was continued.

Shipboard scientists examine the log sheet acquired by LWD hole.
>>Expedition 314 Photo Gallery

Upon return of the LWD logging tools on deck, data were downloaded from the tools. Due to apparent damage during Hole C0001D drilling, density and porosity data and seismic waveform data from the seismic LWD tool could not immediately be retrieved from memory. The tool was sent to the land base to retrieve the data from memory and repair the tool. Two LWD technicians boarded Chikyu to troubleshoot the tool, and determined that this tool also had to be transferred off the ship to land base. Meanwhile, on October 9, the science party received some data including resistivity and gamma imaging and started analyzing the data. Sonic data processing was finished by the data specialist onboard, in consultation with scientists, with results provided to the scientists on October 11. The entire scientific party is now working on the analysis of the logging data from Site C0001.
Continued the preparation for the coring expeditions, maintenance, instrument setup and rearrangements were made. Geo-technical core measurement data were input to J-CORES system, simulation of geochemistry WRC measurements with X-ray CT, and core dry run were also carried out.
Weekly safety drill (helicopter crash and abandon ship drill) was held on October 7.

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Weekly report #2

IODP NanTroSEIZE Stage 1:
Expedition 314: NanTroSEIZE LWD Transect
Weekly Report #2
Date 05/Oct/2007

Preparation for geotechnical coring began on 29 September at Hole C0001B and 30m cores were taken from the seafloor at 2189m water depth on 30 September. Running into the hole with LWD assembly commenced on October 1st. Hole C0001C was spudded in at 19:15. The hole inclination was found to be 6 degrees caused by strong Kuroshio current. Hence the string was pulled out of the hole and moved to new site nearby. Hole C0001D was spudded on 2nd October. To prevent a hole deviation, the drill pipe and bit were jetted 70 m in and rotary drilling began at 30 m/hr rate of penetration. Progress was slowed by tight hole and high torque conditions. Utilized the drilling data of Pilot Hole A, drilling conditions improved and reached 627 meter below seafloor on 4th October.

Shipboard Scientist, Maria-Jose Jurado Rodriguez (Spain) is in (real-time) discussion with other scientists by pointing out at the real-time log data from the first NanTroSEIZE LWD hole.
>>Expedition 314 Photo Gallery

Final confirmation and practice for the LWD data processing was carried out among four sub-groups scientists with support from the Core-Log-Seismic-Integration staff. The whole science party finished Safety Management System (SMS) lectures, and participated in biweekly Safety Management Meeting. On Hole C0001B pilot cores, X-ray CT, MSCL-W, and Moisture and Density measurements were conducted. Science seminars were held continuously, covering 20 topics. LWD real-time data was monitored while the data processing specialist was working and log data quick check, data distribution and processing procedure were confirmed by scientist's working groups. In Lab area, continued the preparation for the coming coring expeditions, maintenance, instrument setup and rearrangements. Measurements of geo-technical cores were conducted in support of wellsite geologist.

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Weekly report #1

IODP NanTroSEIZE Stage 1:
Expedition 314: NanTroSEIZE LWD Transect
Weekly Report #1
Date 28/Sept/2007

The Expedition 314 science party boarded the ship on 19 September after taking the Helicopter Underwater Escape Training and Sea Survival Trainings at JAMSTEC Headquarters on 18 September. Prior to the daily science party meetings, ship safety induction and ship tour were conducted on 20 September, LWD tools introduction was briefed by LWD engineer on 21 September.

LWD engineer explaing the operation of the logging tools to the scientists, Dr. Saneatsu Saito (IFREE/JAMSTEC) and Ayumu Miyakawa (Kyoto University).
>>Expedition 314 Photo Gallery

Chikyu departed the Shingu port for the first site at 16:00 on 21 September 2007. The 44 nm transit was traveled at an average speed of 5.0 knots. Upon arrival to the first site at 01:00 on 22 September, set ship in Dynamic Position mode.
After confirming the site location with ROV (Remotely Operated Vehicle), drilling began at Hole C0001A at 12:15 of September 25. Faster control ROP (Rate of Penetration) after jet in to the depth 70 m, drilling went smoothly up to the depth of 498 mbsf (meter below seafloor). Tools getting stuck from that depth even spotting HiVis drilling fluid at connections. After changing more circulation and slower ROP, drilling continued to the Target Depth of 1000 mbsf at 12:45 of September 27. Preparation for the GeoTech coring was started and maintenance at various instruments on the drill floor and derrick.

Logging data analysis software trainings were conducted, and then scientists practiced in their available time in later days. Science seminar began on 23 September with daily schedule covering topics on previous Nankai Trough LWD drilling review, lithostratigraphy, structural and physical properties, log-seismic integration and modeling of accretionary prisms. Since the start of the pilot hole drilling, science party closely monitored on the real-time data in the lab area and at the lab-roof area while discussing with OSI, drilling engineer and well-site geologist.

As part of the preparation for the next coring expeditions, Lab technicians are working in the lab area for maintenance, instrument setup and rearrangements. Training for the core flow for the Geo-Tech core was also done.