IODP Expeditions 367 and 368
South China Sea Rifted Margin
Daily Science Report for 10–11 June 2017
Location: In transit to/arrived at Lingang Terminal, Shanghai
Science Update: After a four day transit, we arrived in Shanghai, China. South China Sea Rifted Margin Expedition 368 concluded with the first line ashore at Lingang Terminal at 1212 h on 11 June. The science party submitted all finalized science reports and all shipboard work was completed.
Daily Science Report for 9 June 2017
Location: In transit to Shanghai
Science Update: We continued our transit to Shanghai with an estimated time of arrival at the pilot station of 0800 h on 11 June. The science party is finalizing the Site U1504 and U1505 reports. At 1100 h, Expedition 367 and 368 scientists held a meeting to discuss postcruise research plans.
Daily Science Report for 8 June 2017
Location: In transit to Shanghai
Science Update: We continued our transit to Shanghai. Estimated time of arrival at the pilot station is 0800 h on 11 June. The science party is completing and submitting their Sites U1504 and U1505 reports.
Daily Science Report for 7 June 2017
Location:
Hole U1504B (alternate Site SCSII-27A, 18°50.8213′N, 116°14.5978′E, water depth 2943.0 mbsl)
Transit to Shanghai
Science Update: Core U1504B-20R penetrated from 4.7 m to 200.0 m and recovered 0.79 m (17%). Coring was ended due to time, and the bit was recovered, clearing the seafloor at 0455 h and arriving back on the rig floor at 1040 h. The rig floor was secured and the JOIDES Resolution was underway for Shanghai at 1200 h.
Cores U1504B-17R to 20R consist of calc-silicate schist with granofels clasts and epidote chlorite schist. Scientists continue to collect and analyze Hole U1504B data and work on Site U1504 and U1505 reports. At noon, the science summary meeting for Site U1505 was held with the participation of the Expedition 367 Scientists.
Daily Science Report for 6 June 2017
Location: Hole U1504B (alternate Site SCSII-27A, 18°50.8213′N, 116°14.5978′E, water depth 2943.0 mbsl)
Science Update: Cores U1504B-13R to 19R penetrated from 156.2 to 195.3 m and recovered 8 m (20%). Recovery ranged from 6% to 49% (average 22%). Generally, intervals of lowest core recovery (Cores U1504B-16R and 17R, <16%) were associated with faster penetration rates (>6 m/h), while intervals of highest core recovery (>20%) were associated with slower penetration rates (~4 m/h). Cores U1504B-9R and 16R consist of calc-silicate schist with granofels clasts.
Scientists continue to collect and analyze Hole U1504B data and to prepare Site U1504 reports, as well as finalize their presentations for the Site U1505 science summary meeting.
Daily Science Report for 5 June 2017
Location: Hole U1504B (alternate Site SCSII-27A, 18°50.8213′N, 116°14.5978′E, water depth 2943.0 mbsl)
Science Update: We started RCB coring at 88.2 m and Cores U1504B-2R to 12R penetrated to 156.2 m by midnight. Core recovery for this interval is 12.74 m (19%). Core recovery varied by lithology, ranging from 43% in Core U1504B-2R (foraminifer-rich nannofossil ooze), to 2% in Cores U1504B-3R and 4R (clast-supported limestone with coral fragments), to 21% in Cores U1504B-5R through 12R (epidote chlorite schist and epidote chlorite breccia).
Scientists continue to collect and analyze Hole U1504B data and prepare Site U1504 reports, as well as finalize their presentations for tomorrow’s Site U1505 science summary meeting.
Daily Science Report for 4 June 2017
Location:
Hole U1505D (alternate Site SCSII-3D, 18°55.0458′N, 115°51.5501′E, water depth 2917.0 mbsl)
Return to Site U1504
Hole U1504B (alternate Site SCSII-27A, 18°50.8213′N, 116°14.5978′E, water depth 2943.0 mbsl)
Science Update: The 22 nmi voyage back to Site U1504 (alternate Site SCSII-27A) was completed at 0400 h. An RCB BHA was made up and the drill string was lowered to 2775.6 mbsl, followed by the camera system, which was used to observe the bit tag the seafloor to determine the water depth. Before drilling began, the rig crew once again replaced the clutch diaphragm of the drawworks with the last new spare left onboard. These repairs lasted 7.75 h. The bit was then lowered the remaining distance to the seafloor. After determining the water depth (2843.0 m), the camera system was recovered, and Hole U1504B was started at 2245 h. By midnight we had drilled without coring to 68.5 m.
Cores U1505D-13H to 20H consist of interbedded nannofossil ooze with clay and nannofossil ooze with foraminifera. Scientists continue to collect and analyze data from Sites U1505 and U1504 and review Site U1504 reports.
Daily Science Report for 3 June 2017
Location: Hole U1505D (alternate Site SCSII-3D, 18°55.0458′N, 115°51.5501′E, water depth 2917.0 mbsl)
Science Update: APC coring of Hole U1505D was finalized at 1645 h after retrieving Core 20H from 184.5 m. This hole successfully achieved its primary objective of obtaining a complete copy of the Pliocene–Pleistocene section. Total core recovered from Hole U1505D is 191.4 m (109%). The drill string was recovered and operations at Site U1505 ended at 2310 h.
Cores U1505D-1H to 12H consist of foraminifera-rich nannofossil ooze with clay. The three uppermost cores are rich in siliceous microfossils. Scientists continue to collect and analyze Site U1505 data and review Site U1504 reports.
Our plan for the remaining few days of the expedition is to return to Site U1504 and core deeper into basement than Hole U1504A penetrated.
Daily Science Report for 2 June 2017
Location:
Hole U1505C (alternate Site SCSII-3D, 18°55.0570′N, 115°51.5491′E, water depth 2917.4 mbsl)
Hole U1505D (alternate Site SCSII-3D, 18°55.0458′N, 115°51.5501′E, water depth 2917.0 mbsl)
Science Update: Coring of Hole U1505C was completed after recovering Cores 62X to 64X (451.6–480.2 m; 104% recovery). Total core recovered in Hole U1505C was 480.15 m (100%). Following the retrieval of the last core at 0650 h, the hole was circulated with heavy mud and the drill string was pulled back, placing the bit at 80.1 m in preparation for logging. A modified triple combo tool string (with sonic) was assembled and lowered through the drill string and out into the open hole. As it descended, the bottom of the tool string encountered an obstruction at 341.2 m. The tool string was unable to pass through this obstruction. Log data was collected upwards from this depth. The caliper indicated that the hole diameter was too large (>14 inch) for effectively collecting useful data with the FMS and VSI tool strings. Therefore, the decision was made to end downhole logging operations in Hole U1505C. The triple combo tool string was recovered and rigged down by 1715 h. The bit was pulled up above the seafloor and the vessel was offset 20 m south to start Hole U1505D. With the bit at 2912 m (~5 m above the seafloor), Hole U1505D was started at 2200 h, recovering Cores 1H and 2H. Core U1501C-1H recovered 4 m of sediment (99%) and established the seafloor at 2917 mbsl. Core U1505D-2H extended the hole to 13.5 m, recovering 9.6 m (101%).
Scientists held the Hole U1504A science summary meeting with the participation of Expedition 367 scientists at their noon crossover, continued collecting and analyzing Site U1505 data, and submited Site U1504 reports.
Daily Science Report for 1 June 2017
Location: Hole U1505C (alternate Site SCSII-3D, 18°55.0570′N, 115°51.5491′E, water depth 2917.4 mbsl)
Science Update: Cores U1505C-53X to 61X penetrated from 365.2 to 451.6 m, recovering 82 m (95%). The plan is to continue coring until ~480 m, which is our depth/weight limit for operating without the low clutch of the drawworks. Cores U1505C-44F to 56X primarily consist of greenish gray to dark gray clay rich nannofossil ooze with foraminifera. Cores U1505C-57X and 58X consist of dark greenish gray silty clay. Bioturbation ranges from heavy to complete. Biostratigraphic markers indicate a late Eocene age for the base of Core U1505C-59X. Scientists are collecting and analyzing Site U1505 data, submitting Site U1504 reports, and preparing presentations for tomorrow’s Site U1504 summary meeting.