IODP Expedition 368X
Return to Hole U1503A (South China Sea)
Daily Science Report for 30 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E; water depth 3868 m; proposed Site SCSII-9B)
Science Update: Cores 68R to 74R penetrated 1586.1–1628.0 m and recovered 11.14 m. Recovery was low (3%) in Core 68R but increased to an average of 35% in Cores 69R to 74R.
Core 68R and the upper portion of Core 69R consist of lithified nannofossil-rich claystone and siltstone. The lower section of Core 69R and Cores 70R to 74R consist of plagioclase phyric basalt, with some glassy margins. Drilling disturbance (fragmenting) varies from moderate to high.
Daily Science Report for 29 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E; water depth 3868 m; proposed Site SCSII-9B)
Science Update: Cores 63R to 67R penetrated 1552.3–1586.1 m and recovered 0.71 m (2%). Penetration rates remain low and average 1.7 m/h.
Core 61R consists of lithified reddish brown clay-rich chalk in the upper 7 cm. The bottom of Core 61R and Cores 62R to 65R consist of lithified nannofossil-rich claystone with bioturbation. Drilling disturbance (fragmenting and fracturing) varies from moderate to high.
Daily Science Report for 28 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E; water depth 3868 m; proposed Site SCSII-9B)
Science Update: Cores 58R to 62R penetrated 1518.4–1552.3 m and recovered 0.74 m (3%). Penetration rates have slowed to an average of 1.6 m/h.
Core 58R consists of lithified dark reddish brown claystone with no bioturbation. Cores 59R and 60R consist of chalk with moderate bioturbation. Drilling disturbance (fragmenting) varies from slight to high.
Daily Science Report for 27 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E; water depth 3868 m; proposed Site SCSII-9B)
Science Update: The drill pipe was lowered to 3855 m below the rig floor and at 0545 h the subsea camera was deployed. The secondary free-fall funnel was clearly visible and Hole U1503A was reentered at 0830 h. The subsea camera returned to the surface and the drill pipe was lowered into the hole until a bridge was encountered at 1345.0 m. After spending nearly 7 h washing and reaming from 1345.0 to 1528.0 m, we resumed coring at 2100 h.
The science party laboratory groups each gave a presentation on the data collected from Cores 2R–57R.
Daily Science Report for 26 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E; water depth 3868 m; proposed Site SCSII-9B)
Science Update: Core 57R penetrated 1518.4–1528.0 m and recovered 1.2 m (13%). At 0400 h we started operations to replace the drill bit. The pipe was raised to 1383 m within the open hole (casing extends to 991.5 m) and 200 barrels of heavy mud were pumped in to maintain hole stability. The subsea camera was lowered and we pulled the bit out of the hole at 1247 h. The secondary free-fall funnel was upright and clearly visible. At 2115 h the bottom-hole assembly (BHA) was back at the rig floor. The drill bit was replaced and the BHA was lowered to 741 m below rig floor by the end of the day.
Cores 55R to 57R consist primarily of well consolidated dark reddish brown claystone. An interval of chalk is present in Core 55R (1501 m). Core 55R contains moderate to heavy bioturbation. Cores 56R and 57R contain slight bioturbation. Drilling disturbance (fragmenting) varies from slight to high.
Daily Science Report for 25 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E; water depth 3868 m; proposed Site SCSII-9B)
Science Update: Cores 52R to 56R penetrated 1470.5–1518.4 m and recovered 22.94 m (48%). Penetration rates have slowed and average near 4 m/h.
Cores 49R to 54R consist of well consolidated claystone and siltstone. Intervals of claystone and siltstone contain slight to heavy bioturbation. Drilling disturbance (fragmenting) varies from slight to high.
Daily Science Report for 24 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E; water depth 3868 m; proposed Site SCSII-9B)
Science Update: Cores 46R to 51R penetrated 1412.9–1470.5 m and recovered 26.35 m (46%). Core recovery was less variable, ranging from 32% to 58%.
Cores 42R to 48R consist of well consolidated claystone, siltstone, and sandstone. Intervals of claystone and siltstone contain slight to heavy bioturbation. Drilling disturbance (fragmenting) varies from moderate to high.
Daily Science Report for 23 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E; water depth 3868 m; proposed Site SCSII-9B)
Science Update: Cores 37R to 45R penetrated 1326.5–1412.9 m and recovered 19.54 m (23%). Core recovery remains highly variable, ranging from 0% to 72%.
Cores 34R to 41R consist of well consolidated claystone and sandstone. Intervals of claystone contain moderate bioturbation. Drilling disturbance (fragmenting) varies from slight to high.
Daily Science Report for 22 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E; water depth 3868 m; proposed Site SCSII-9B)
Science Update: Cores 26R to 36R penetrated 1221.0–1326.5 m and recovered 10.39 m (10%). Core recovery remains variable, ranging from 0% to 32%.
Cores 22R to 33R consist of well consolidated to lithified claystone and sandstone. Intervals of claystone contain moderate bioturbation. Drilling disturbance (fracturing and fragmenting) varies from slight to high.
Daily Science Report for 21 November 2018
Location: Hole U1503A (18°8.6300′N, 116°18.8456′E, water depth 3868 m; proposed Site SCSII-9B)
Science Update: Cores 15R to 25R penetrated 1115.6–1221.0 m and recovered 16.24 m (15%). Core recovery remains highly variable, ranging from 0% to 49%.
Cores 10R to 21R consist of well consolidated to lithified claystone and sandstone. Intervals of claystone contain moderate bioturbation.
Daily Science Report for 20 November 2018
Location: Site U1503 (18°8.6300′N, 116°18.8456′E, water depth 3868 m; proposed Site SCSII-9B)
Science Update: Cores 4R to 14R penetrated 1010.2–1115.6 m and recovered 25.16 m (24%). Core recovery is highly variable, ranging from 0% to 86%.
Cores 2R to 9R consist of well consolidated to lithified claystone and sandstone. Intervals of claystone contain moderate bioturbation.
Daily Science Report for 19 November 2018
Location: Site U1503 (18°8.6300′N, 116°18.8456′E, water depth 3868 m; proposed Site SCSII-9B)
Science Update: Hole U1503A was reentered at 0039 h and the subsea camera was recovered. Due to the position of the free-fall funnel (FFF) installed during Expedition 368 (~1–2 m below seafloor), a secondary FFF was assembled and deployed. While installing the top drive, a drill pipe misalignment was caused by currents and the pipe had to be repositioned before the top drive could be installed. The hole was cleaned with a high viscosity mud sweep and we began rotary core barrel (RCB) coring. We recovered Core 2R and 3R (995.1–1010.2 m), with 33% and 4% recovery, respectively.
The science party received training in the Petrophysics Laboratory, and an introduction to the Section Half Imaging Logger and Section Half Multisensor Logger.
Daily Science Report for 18 November 2018
Location: Site U1503 (18°8.6300′N, 116°18.8456′E, water depth 3868 m; proposed Site SCSII-9B)
Science Update: The JOIDES Resolution completed the 284 nmi transit and arrived at Site U1503 at 0900 h. The thrusters were lowered and the ship was in full dynamic positioning mode by 0953 h. The crew then removed the upper guide horn, assembled the drill string, and reached 2990 m below rig floor by 1945 h. The subsea camera was deployed and started the search for Hole U1503A. The Expedition 368X science party continued training in the laboratories, including introductions to the handheld portable X-ray fluorescence spectrometer, curation, and description software. The science party also received a lifeboat safety orientation and tours of the bridge and dynamic positioning system.
Daily Science Report for 17 November 2018
Location: In transit to Hole U1503A (18°8.6300′N, 116°18.8456′E, water depth 3868 m; proposed Site SCSII-9B)
Science Update: The pilot came onboard at 0754 h, and the last line was released at 0824 h to start the 284 nmi transit to Hole U1503A. After enjoying the morning departure, the laboratory teams continued to reacquaint themselves with the instruments and protocols in each laboratory.
Daily Science Report for 16 November 2018
Location: China Merchant Wharf, Hong Kong
Science Update: The Expedition 368X science party continued expedition preparations, which included an orientation to life at sea, general safety introductions and tours, and introductions to the laboratories. The Expedition Project Manager gave a presentation about expedition expectations, tasks, and reports. The science party also received shipboard safety introductions by the Captain, First Mate, and Physician. Fuel was received by barge and the Schlumberger wireline active heave compensator was repaired and tested. Core barrels were assembled and spaced out in preparation for departure and operations.
Daily Science Report for 15 November 2018
Location: China Merchant Wharf, Hong Kong
Science Update: The Return to Hole U1503A (South China Sea) Expedition 368X began at 0800 h. The Expedition 368X science party and IODP JRSO technical staff boarded the vessel and settled into their cabins. The scientists began expedition preparation, including introductions and an orientation to shipboard computing resources. Hazardous freight and potable water was received by barge. An air freight shipment was received with parts needed to repair the hydraulic unit tank on the Schlumberger wireline active heave compensator.