IODP Expedition 384
Engineering Testing
Daily Science Report for 31 July 2020
Location: Hole U1555A (60°13.683′N, 28°29.969′W; water depth 1512 m; proposed Site REYK-13A)
Science Update: Drilling with the mud motor and 12¼ inch TCI bit continued from 223.6 m driller’s depth below sea floor (DSF). We reached the target basement penetration of ~100 m (97.4 m exactly) at 2000 h, at 282.0 m DSF. The driller had to pull the bit back by ~30 m three times for hole cleaning with additional mud sweeps at 242.6 m DSF (0415 h), 252.6 m DSF (0915 h), and 262.6 m DSF (1045 h). For the third mitigation effort, the hole had to be reamed from 262.6 to 242.6 m DSF. The rest of the day was spent retrieving the drill string, with the bit clearing the rig floor at 2235 h.
The IODP JRSO staff continued Site U1554 core characterization with section half and discrete sample measurements.
Daily Science Report for 30 July 2020
Location: Hole U1555A (60°13.683′N, 28°29.969′W; water depth 1512 m; proposed Site REYK-13A)
Science Update: Deployment of the drill string with a mud motor and a 12¼ inch TCI bit was completed and we began drilling Hole U1555A at 0015 h. The goal at this hole was to penetrate the 210 m of sediment, as estimated from geophysical site survey data, and then deepen the hole ~100 m into the basaltic basement, or drill for ~40 h, whichever would come first. The water depth of 1512 m was determined based on precision depth recorder (PDR) readings and could not be confirmed precisely by tagging with the drill string. Sediment penetration proceeded at a controlled advancement rate of ~40 m/h. At 0545 h, with the bit at ~185 m driller’s depth below seafloor (DRF), the formation stiffened and advancement slowed by an order of magnitude, to typically <5 m/h. At 1930 h the bit got stuck at 224 m DRF. The rest of the day was spent with mitigation measures, including offsetting the ship to set the slips, circulating mud sweeps, and working the pipe free. The bit was raised to 213 m DRF for further mud circulation and hole cleaning.
The IODP JRSO staff completed whole-round core logging of the Site U1554 cores. We began to split the core sections and perform additional routine core characterization. These measurements include visual light and X-ray imaging, color reflectance and magnetic susceptibility measurements on the Section Half Multisensor Logger (SHMSL), magnetic remanence logging with the superconducting rock magnetometer, moisture and density and magnetic property measurements on a small set of discrete samples, and rudimentary core description.
Daily Science Report for 29 July 2020
Location: Hole U1555A (60°13.683′N, 28°29.969′W; water depth 1520 m; proposed Site REYK-13A)
Science Update: The ship was offset 20 m west of Hole U1554C and coring in Hole U1554D began at 0045 h. After drilling down to 14 m driller’s depth below sea floor (DSF), we cored a single Core 2H from 14 to 23.5 m DSF, with a recovery of 9.72 m (102%). The drill string was retrieved and cleared the rig floor at 0715 h, ending operations in Hole U1554D.
The rig was secured and the ship began the transit to Site U1555 (proposed Site REYK-13A) at 0900 h. This is the site where the primary objectives of Expedition 384 will be addressed: the performance testing of three types of drill bits, an underreamer, and a PDC coring bit. We arrived at Site U1555 at 1518 h and switched to dynamic positioning mode. For the rest of the day the drill crew made up the mud motor and a 12¼ inch TCI bit, conducted flow tests, assembled the bottom-hole assembly, and began deploying the drill string.
Whole-round core logging of all Site U1554 cores continued.
Daily Science Report for 28 July 2020
Location: Hole U1554C (60°07.495′N, 26°42.075′W; water depth 1865 m; proposed Site REYK-06A)
Science Update: We completed APC coring in Hole U1554A at 0625 h with Core 8H to 72.2 m driller’s depth below seafloor (DSF), with a recovery of 74.7 m (103%). The ship was offset 20 m to the east and Hole U1554B was completed at 1515 h with Core 8H to 76.0 m DSF, with a recovery of 76.8 m (101%). The ship was offset 20 m to the south and we completed Hole U1554C at 2330 h with Core 8H to 75.0 m DSF, with a recovery of 77.0 m (103%). Core orientation was measured on each core in each hole.
All cores were rapidly measured for magnetic susceptibility and gamma ray attenuation on the Special Task Multisensor Logger (STMSL) to allow real-time stratigraphic correlation and ensure that all coring gaps in a hole were covered by cores in at least one of the adjacent holes. Higher resolution measurements on the Whole-Round Multisensor Logger (WRMSL), which also includes P-wave velocity, and on the Natural Gamma Radiation Logger (NGRL), are in progress. A composite depth scale was constructed to 83.29 m core composite depth below seafloor (CCSF) using the excellent magnetic susceptibility signal in the sediments. This will allow us to establish a complete stratigraphic splice for Site U1554.
Daily Science Report for 27 July 2020
Location: Hole U1554A (60°07.504′N, 026°42.096′W; water depth 1865 m; proposed Site REYK-06A)
Science Update: We completed the last 55 nmi of the 1094 nmi transit to Site U1554 (proposed Site REYK-06A). The transit ended at 0629 h when we established dynamic positioning. An APC/XCB bottom-hole assembly was made up, the drill pipe was assembled and conditioned, and Hole U1554A was started at 2300 h with a 5.7 m long mudline core.
Daily Science Report for 26 July 2020
Location: In transit to proposed Site REYK-06A
Science Update: We completed 265 nmi for a total of 1039 of the 1094 nmi transit to proposed Site REYK-06A. Preparations and training for coring and laboratory operations continued.
Expected time of arrival at proposed Site REYK-06A is 0600 h on 27 July.
Daily Science Report for 25 July 2020
Location: In transit to proposed Site REYK-06A
Science Update: We completed 278 nmi for a total of 774 of the 1094 nmi transit to proposed Site REYK-06A. Preparations and training for coring and laboratory operations continued.
Expected time of arrival at proposed Site REYK-06A is 0600 h on 27 July.
Daily Science Report for 24 July 2020
Location: Underway to proposed Site REYK-06A
Science Update: We completed 305 nmi for a total of 496 of the 1094 nmi transit. Preparations for the advanced piston corer (APC) core orientation tests continued with a demonstration by Siem Offshore specialists of how the APC core barrel is assembled, including the core orientation tool, and readied for deployment. JRSO personnel also joined a first conference on how the JRSO can promote diversity on IODP expeditions, within the organization, and across the TAMU campus.
The ship’s clocks were set back 1 h at 0200 h and we are now in time zone UTC + 1.
ETA at proposed Site REYK-06A is 0600 h on 27 July.
Daily Science Report for 23 July 2020
Location: In transit to proposed Site REYK-06A
Science Update: After conducting final port call activities, the pilot boarded the ship at 0656 h and we left port at 0730 h for the voyage to proposed Site REYK-06A. Senior JRSO and Siem Offshore personnel met to discuss operations at proposed Sites REYK-06A and REYK-13A. Preparations for the advanced piston corer (APC) core orientation tests continued, including assembly and measurement tests for both types of available tools.
We completed 191 nmi of the 1094 nmi transit. Estimated time of arrival at proposed Site REYK-06A is the morning of 27 July.
Daily Science Report for 22 July 2020
Location: Berth 16, Port of Kristiansand, Norway
Science Update: Final ship maintenance and shipment deliveries were completed. Testing of the APC core orientation tools has begun in preparation for coring tests at proposed Site REYK-06A.
Departure from Kristiansand is scheduled for 0700 h tomorrow, 23 July.
Daily Science Report for 21 July 2020
Location: Berth 16, Port of Kristiansand, Norway
Science Update: The final crew members and JRSO staff boarded the ship at 1000 h. The top drive repair was completed and the Siem Offshore air freight was loaded.
Final ship maintenance and shipment deliveries are expected to be completed on 22 July. Departure from Kristiansand is scheduled for 0700 h on 23 July.
Daily Science Report for 20 July 2020
Location: Berth 16, Port of Kristiansand, Norway
Science Update: Expedition 384 (Engineering Testing) began at 1000 h (UTC + 2 h) with the arrival of 17 JRSO personnel on the JOIDES Resolution (JR). One more JRSO and several Siem Offshore personnel are expected to board on 21 July. All 18 JRSO personnel passed a COVID-19 test and completed a two-week quarantine at home, and after arrival in Kristiansand spent an additional 5 d quarantined in a hotel where they passed two more COVID-19 tests. All shipboard personnel are following social distancing and mask wearing protocols.
Expedition 384 is dedicated to engineering testing as it relates to deep (>1 km) drilling and coring in igneous ocean crust. The primary objective of Expedition 384 is to drill a series of holes using three types of drill bits: a tungsten carbide insert (TCI) tricone bit that is more robust than used so far on the JR, a polycrystalline diamond compact (PDC) bit, and a TCI/PDC hybrid bit. Additional tests include the deployment of a block type underreamer as well as a PDC coring bit to obtain samples for geotechnical testing. These drilling, hole opening, and coring objectives were the top priorities of the Deep Crustal Drilling Engineering Working Group, which convened in 2017 to discuss issues with crustal drilling, and the JOIDES Resolution Facility Board in 2018.
The site location for these tests has evolved over the past two years as a result of JR schedule changes. The current primary site is proposed Site REYK-13A (1520 m water depth) from postponed IODP Expedition 395, where several holes will be drilled through the 210 m sediment section and ~100 m into basalt. A potential second site is Integrated Ocean Drilling Program Site U1309, where another hole would be drilled into gabbroic rocks exposed at the seafloor. Operations at proposed Site REYK-13A and Site U1309 are projected to take ~22 d.
Additional operating time became available for Expedition 384 as a result of the latest JR schedule change dictated by the COVID-19 situation. A secondary objective was therefore added: the assessment and potential improvement of current procedures for advanced piston corer (APC) core orientation. A total of ~5 d is allocated to triple-coring the top 70 m of sediment at proposed Site REYK-6A (postponed Expedition 395), located 54 nmi east of proposed Site REYK-13A.
The mechanical installation of the top drive is currently in progress. Departure from Kristiansand is planned for 23 July.