IODP Expedition 390
South Atlantic Transect 1
Daily Science Report for 30 April 2022
Location: Hole U1556B (30°56.5244′S, 26°41.9472′W, water depth 5001.8 mbsl)
Science Update: Cores U1556B-36R to 41R advanced from 518.4 to 547.5 mbsf and recovered 29.0 m (66%). All cores were half length. Mud sweeps were pumped after every half core.
Cores U1556B-32R to 34R consist of sparsely to moderately olivine phyric basalt with cryptocrystalline groundmass. Section 34R-7 contains a hyaloclastite interval. Most sections were emplaced as pillow lava flows, though Core 34R comprises a massive lava flow with microcrystalline groundmass. Glass is moderately to highly altered and present along chilled margins. NGR was high in Cores 34R to 38R. Alteration petrology of these cores has not yet been described. The science party completed reports on the sediment obtained from Site U1557 during Expedition 390C.
Daily Science Report for 29 April 2022
Location: Hole U1556B (30°56.5244′S, 26°41.9472′W, water depth 5001.8 mbsl)
Science Update: Cores U1556B-31R to 35R advanced from 489.0 to 518.4 mbsf and recovered 21.68 m (74%). It was necessary to run the deplugger tool following Core 34R as we were not able to circulate, likely due to fall-in lodged within the jets on the bit. The deplugger successfully restored circulation and we continued drilling half cores for the remainder of the day. Crew and JRSO staff participated in a security drill.
Cores U1556B-29R to 31R consist of sparsely olivine phyric basalt with aphyric chilled margins, emplaced as pillow lava flows. Groundmass is cryptocrystalline, and glass, when present, is moderately to highly altered. There are abundant veins and occasional radial pipe vesicles.
Daily Science Report for 28 April 2022
Location: Hole U1556B (30°56.5244′S, 26°41.9472′W, water depth 5001.8 mbsl)
Science Update: The subsea camera system with the Conductivity-Temperature-Depth (CTD) sensor attached was deployed to aid reentry of Hole U1556B with a new RCB drill bit. Reentry occurred at 0625 h, and the subsea camera system was recovered and secured. Drilling resumed and Cores U1556B-29R and 30R advanced 13.4 m with 9.48 m recovered (71%) for a total penetration depth of 489.0 mbsf.
Cores U1556B-26R to 28R contain aphyric basalt predominantly emplaced as pillow lavas. The basalts have cryptocrystalline groundmass. Fresh glass occurs along chilled margins and in hyaloclastite breccia.
Daily Science Report for 27 April 2022
Location: Hole U1556B (30°56.5244′S, 26°41.9472′W, water depth 5001.8 mbsl)
Science Update: Core U1556B-28R advanced from 470.6 to 475.6 mbsf and recovered 3.51 m (70%). A mud sweep was conducted after Core 28R, and we began the process of pulling out of the hole to conduct a bit change. The bit reached the seafloor at 0420 h and reached the rig floor at 1335 h. At midnight, the BHA with a new bit was approaching the seafloor and we were preparing to deploy the subsea camera system.
The lithology of Cores U1556B-21R to 25R transitions from moderately to sparsely olivine phyric and then aphyric basalt downcore. Hyaloclastite breccia in Core 22R is mostly palagonite and basaltic glass with calcite precipitated in the void spaces. Breccia in Core 25R has a higher proportion of basalt to glass. The science party held its first site meeting to share results from advanced piston corer/extended core barrel (APC/XCB) coring in Hole U1557B. Coring was conducted during Expedition 390C but the core material was described during the Expedition 390 transit.
Daily Science Report for 26 April 2022
Location: Hole U1556B (30°56.5244′S, 26°41.9472′W, water depth 5001.8 mbsl)
Science Update: Cores U1556B-23R to 27R advanced from 436.6 to 470.6 mbsf and recovered 13.3 m (39%). Cores 25R to 27R were half-length cores, after several full-length advances resulted in jammed core barrels and collapsed or cracked liners.
Cores U1556B-17R to 20R were described for igneous and alteration petrology. Sections 17R-1 and 2 are sparsely olivine phyric basalt with interpillow hyaloclastite. From Section 17R-3 downcore, the predominant lithology is moderately olivine phyric basalt with cryptocrystalline groundmass. Veins are the most common fill type, with occasional vesicles and breccia. Alteration halos range in color from orange to dark brown to light gray.
After 14 days since last contact with shore, the COVID mitigation period officially ended at 1135 h.
Daily Science Report for 25 April 2022
Location: Hole U1556B (30°56.5244′S, 26°41.9472′W, water depth 5001.8 mbsl)
Science Update: Cores U1556B-18R to 24R advanced from 388.0 to 456.1 mbsf and recovered 27.8 m (41%).
Cores U1556B-13R to 16R were described for igneous and alteration petrology. Section 13R-1 is a hyaloclastite. The rest of Core 13R and Cores 14R to 16R are moderately olivine phyric basalts, emplaced as pillow lava flows and containing inter-pillow hyaloclastite. Fresh glass fragments are present, including in the interiors of large clasts in the hyaloclastite. Basalt alteration is moderate, with altered segments brown in color, and with a pseudomorphic texture. Veins are present, with occasional vesicles and breccia.
Shipboard COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 24 April 2022
Location: Hole U1556B (30°56.5244′S, 26°41.9472′W, water depth 5001.8 mbsl)
Science Update: Cores U1556B-11R to 17R advanced from 339.3 to 388.0 mbsf and recovered 18.7 m (38%). Core recovery was highly variable, ranging from 15%–77%, and appeared to be correlated with lithology.
Core U1556B-8R contains sedimentary breccia and hyaloclastite in a limestone matrix. Core 9R to Section U1556B-12R-1 are cryptocrystalline moderately olivine phyric basalts, predominantly emplaced as pillow lava flows. Section 12R-2 contains breccia with hyaloclastite in a limestone matrix. Moderately to highly altered glass fragments are found throughout the cores. The science party and JRSO staff took part in a fire and boat drill. Shipboard COVID-19 mitigation protocols are being followed.
Daily Science Report for 23 April 2022
Location: Hole U1556B (30°56.5244′S, 26°41.9472′W, water depth 5001.8 mbsl)
Science Update: Cores U1556B-4R to 10R advanced from 305.1 to 339.3 mbsf and recovered 19.8 m (58%). Core recovery was variable, ranging from 44%–71%.
Sediment in the upper section of Core U1556B-2R consists of silty clay and nannofossil ooze. Cores 2R and 3R contain a mix of moderately to sparsely olivine phyric basalt and sedimentary breccia. Core 4R represents a massive lava flow and contains sparsely olivine phyric and aphyric basalt. Cores 5R to 7R contain breccia with a hyaloclastite matrix and calcite cement. Glass content is variable in Cores 2R–4R and consistently present in Cores 5R–7R, manifesting primarily as chilled margins, palagonite, and fragments. Breccias, veins, and vesicles most commonly have polycrystalline fill, but botryoidal, massive, or vuggy fill types are also observed. Fill material is iron oxides, calcite, and saponite.
Shipboard COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 22 April 2022
Location: Site U1556 (30°56.5244′S, 26°41.9472′W)
Science Update: The day began with the subsea camera system deployed, guiding reentry of Hole U1556B with the RCB BHA. Reentry was made at 0405 h and the subsea camera system was brought back up to the surface and recovered. Pipe was tripped down the cased hole to 267 meters below seafloor (mbsf) and the top drive picked up. Washing down continued to 291.0 mbsf when the bit contacted a hard layer. The drilled interval from seafloor to 291.0 mbsf was designated as Core 1-1. Core U1556B-2R advanced to 300.3 mbsf and recovered 1.64 m (18%). The decision was made to drill half-length cores. Core U1556B-3R advanced to 305.1 mbsf and recovered 3.57 m (74%). Shipboard COVID-19 mitigation protocols are being followed.
Daily Science Report for 21 April 2022
Location: Site U1556 (30°56.5244′S, 26°41.9472′W)
Science Update: Following arrival on site, the RCB BHA was made up and deployed. We tripped drill pipe to 5011 meters below rig floor (mbrf), and at 1845 h we launched the subsea camera system in order to observe reentry into Hole U1556B, where a reentry system and casing were initially installed during engineering Expeditions 390C and 395E. The subsea camera system was lowered to the seafloor and the Hole U1556B reentry cone was immediately located. An attempt to reenter the hole was made but this stirred up significant sediment, obscuring the cone’s location. Reentry attempts continued past midnight.
The science party made final preparations for receiving core. The microbiologists conducted a walk-through of sampling protocols. Shipboard COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 20 April 2022
Location:
- Underway to Site U1556 (proposed Site SATL-53B)
- Site U1556 (30°56.5244′S, 26°41.9472′W)
Science Update: The vessel transited 260 nmi and arrived at Site U1556 at 2300 h, completing its 2296 nmi voyage from Cape Town, South Africa. We lowered the thrusters and switched from cruise mode into dynamic positioning (DP) mode at 2336 h. The rig floor was released for operations, and at midnight, assembly of the bottom-hole assembly (BHA) for rotary core barrel (RCB) drilling in Hole U1556B was underway.
Core description of Expedition 390C material continued. Holes U1559A, U1556A, U1557A, and U1557B have now been completely described. Cores U1557B-47X to 60X contain pinkish-white calcareous nannofossil ooze that transitions to calcareous nannofossil chalk with foraminifera and then nannofossil-rich calcareous chalk. Occasional volcaniclastics and thin layers of silty clay occur. Samples near the sediment/basement interface are mid-late Paleocene in age.
Shipboard COVID-19 mitigation protocols are being followed. After seven days of daily rapid antigen tests, we transitioned to testing on alternate days. Scientists and JRSO staff received safety training from the ship’s crew in how to properly put on survival suits.
Daily Science Report for 19 April 2022
Location: Underway to Site U1556 (proposed Site SATL-53B)
Science Update: The vessel completed 245 nmi, for a total of 2036 nmi, of the 2296 nmi voyage to Site U1556. Core description of Expedition 390C material continued. Sediment Cores U1557B-32X to 39X contain nannofossil-rich calcareous ooze ranging in color from brown to light gray to pink and are Eocene in age. Cores 40X to 46X contain pink calcareous nannofossil ooze with occasional thin layers of foraminiferal calcareous ooze. Core 41X has several layers of greenish-black volcanic sandy silt. The Stratigraphic Correlators met with the Operations Superintendent and Siem Offshore Toolpushers to discuss options for correlation of Hole U1556A (cored during Expedition 390C) and planned Hole U1556C. Shipboard COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 18 April 2022
Location: Underway to Site U1556 (proposed Site SATL-53B)
Science Update: The vessel completed 252 nmi, for a total of 1791 nmi, of the 2296 nmi voyage to Site U1556. Core description of Expedition 390C material continued. Sediment Cores U1557B-21X to 31X contain alternating layers of pink calcareous nannofossil ooze and brown or reddish-brown silty clay. Thin layers of organic-rich silty clay with nannofossils and foraminiferal nannofossil ooze are observed. Cores 29X to 32X contain a hiatus or condensed interval spanning the early Oligocene to early Eocene. Shipboard COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 17 April 2022
Location: Underway to Site U1556 (proposed Site SATL-53B)
Science Update: The vessel completed 289 nmi, for a total of 1539 nmi, of the 2296 nmi voyage to Site U1556. Core description of Expedition 390C material continued. Sediment Cores U1557B-7H to 20X contain alternating layers of brown silty clay and pink or pinkish-gray calcareous nannofossil ooze. MS and NGR collected during Expedition 390C correlate with these layers. Basement material in Section 63X-3 and Cores 64X to 66X consists primarily of breccia and hyaloclastite. Prior to splitting, these sections were imaged with the DMT core scanner.
Sedimentologists and petrologists received training in safe operation of the portable X-ray fluorescence spectrometer (pXRF). The science party and JRSO staff took part in a fire and boat drill. Shipboard COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 16 April 2022
Location: Underway to Site U1556 (proposed Site SATL-53B)
Science Update: The vessel completed 282 nmi, for a total of 1250 nmi, of the 2296 nmi voyage to Site U1556. Core description of Expedition 390C material continued. Cores U1556A-24X to 25X consist of alternating intervals of dark reddish-brown silty clays and very pale brown or light yellowish-brown calcareous nannofossil ooze. Cores 26X to 30X are almost entirely calcareous nannofossil ooze and date to the upper Paleocene. Core 30X contains the sediment/basement interface. Cores 30X to 33X were curated, imaged with the DMT core scanner, split, and described. Hard rock in Cores 30X to 33X is a peperite with moderately olivine phyric basalt. Cores U1557A-1H and U1557B-1H to 6H contain alternating layers of brown silty clay and pinkish-gray calcareous nannofossil ooze. Core 1H contains a layer of diatom-rich biosiliceous ooze. The base of Core U1557B-6H is early Pliocene in age.
Daily Science Report for 15 April 2022
Location: Underway to Site U1556 (proposed Site SATL-53B)
Science Update: The vessel completed 278 nmi, for a total of 968 nmi, of the 2296 nmi voyage to Site U1556. Preparations for coring continued with the science party submitting their methods sections. Core description of Expedition 390C material continued. Cores U1556A-9H to 23X consist of alternating intervals of silty clay and calcareous nannofossil ooze with sparse bioturbation. The clays transition from brown/light brown to reddish-brown downcore, while the oozes transition from pink to pinkish-white in color downcore. Core 23X is late Oligocene in age. Shipboard COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 14 April 2022
Location: Underway to proposed Site SATL-53B (Site U1556)
Science Update: The vessel completed 263 nmi, for a total of 690 nmi, of the 2296 nmi voyage to proposed Site SATL-53B (Site U1556). The towed magnetometer was deployed at 0630 h after troubleshooting a minor issue. Core description of Expedition 390C material continued. Cores U1556A-2H to 8H consist of alternating layers of brown clay or silty clays and pinkish-white to light gray calcareous nannofossil ooze. Magnetic susceptibility (MS) and natural gamma radiation (NGR) collected during Expedition 390C correlate with these layers. Based on core catcher samples analyzed on shore following Expedition 390C, Cores 2H and 3H are mid-late Pliocene in age. Toothpick sampling of nannofossils to refine the age model is ongoing. Core U1559A-9X, containing hard rock material, was curated, imaged using the Foldio lightbox system in the Microbiology Laboratory, and split. Shipboard COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 13 April 2022
Location: Underway to proposed Site SATL-53B (Site U1556)
Science Update: The vessel completed 268 nmi, for a total of 427 nmi, of the 2296 nmi voyage to proposed Site SATL-53B (Site U1556). The science party worked on methods sections and developed their research sampling plans. Core description of Expedition 390C material continued. Cores U1559A-5X to 7X consist of very pale brown nannofossil ooze. Core U1559A-8X, containing the sediment/basement interface, was split, imaged, and described. Sediment sections are soupy due to 1.5 y of storage in unsplit core liners, but are lithologically similar to overlying cores. Core U1556A-1H consists of brown clay and silty clays with an interval of alternating silty clay and biosiliceous ooze. Shipboard COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 12 April 2022
Location:
- Repair Quay 3, Cape Town, South Africa
- Underway to proposed Site SATL-53B (Site U1556)
Science Update: The pilot boarded the ship at 0812 h and the vessel departed Repair Quay 3, with the last line released at 0836 h. Contractors came aboard during departure to conduct testing of the uninterruptible power supply (UPS) system and to adjust the ship’s magnetic compass. The science party and JRSO staff participated in a fire and boat drill. Sea passage began at 1136 h after the departure of the pilot and the contractors. The vessel completed 159 nmi of the 2296 nmi voyage to proposed Site SATL-53B (Site U1556).
The science party engaged in laboratory-specific activities. The microbiologists and geochemists prepared media for stable isotope- and radioisotope-labeled incubations of samples. Physical properties specialists were trained in running the Whole-Round Multisensor Logger (WRMSL) and Natural Gamma Radiation Logger (NGRL). Description of cores collected during Expeditions 390C and 395E began. These cores were previously analyzed on the WRMSL and NGRL, split, and analyzed with the Section Half Imaging Logger (SHIL) and the Section Half Multisensor Logger (SHMSL). Cores U1559A-1H to 4H transition from pale brown clayey silt with nannofossils to very pale brown or white nannofossil and calcareous oozes. All scientists worked on finishing their methods sections and developing sample plans for discrete shipboard samples.
COVID-19 mitigation protocols are being followed. All members of the science party, staff, and crew took COVID-19 tests.
Daily Science Report for 11 April 2022
Location: Repair Quay 3, Cape Town, South Africa
Science Update: The ship bunkered another load of fuel and received final freight and food deliveries. Five remaining vessel personnel boarded.
Scientists took core flow tours led by JRSO staff to understand the different stages of core curation, processing, and analysis. Work continued on the methods sections and templates for core description in DESCLogik. The Marine Computer Specialists and developers conducted troubleshooting on an issue with reuploading core data collected during Expeditions 390C and 395E that will be used and referenced during this expedition. All participants took a rapid antigen test dockside as part of our ongoing COVID-19 mitigation protocols. PCR tests from 10 April were all negative. The vessel is scheduled to depart 12 April.
Daily Science Report for 10 April 2022
Location: Repair Quay 3, Cape Town, South Africa
Science Update: Port call activities continued with the bunkering of 500.2 mt fuel and pre-expedition checks of propulsion and drilling equipment. Several additional JRSO staff and ship’s crew joined the vessel. Expedition 390 participants took their final planned PCR test for COVID-19 and will begin using rapid tests for the duration of the COVID-19 mitigation period. Scientists were trained in the use of the SampleMaster and DESCLogik software and continued to work on their methods sections. Expedition 390 microbiologists set up and began testing of the dissolved oxygen probe. The vessel is scheduled to depart 12 April.
Daily Science Report for 9 April 2022
Location: Repair Quay 3, Cape Town, South Africa
Science Update: The majority of the Expedition 390 ship’s crew, JRSO staff, and science party cleared immigration, boarded the vessel, and moved into their cabins. All oncoming participants went immediately onto shift as part of the COVID-19 mitigation protocols. Scientists who were on shift in the afternoon received a general presentation on ship safety, took a safety and orientation tour of the vessel, and continued work on their methods chapters. The microbiologists working with stable and radioactive isotopes were given a tour and safety overview of the rad van. JRSO staff moved the DMT core scanner into place in the Core Laboratory. Other portcall activities included distribution of oncoming freight. The vessel is scheduled to depart 12 April.
Daily Science Report for 8 April 2022
Location: Repair Quay 3, Cape Town, South Africa
Science Update: The Expedition 390 scientists, JRSO staff, and ship’s crew continued to quarantine, prior to boarding on 9 April. PCR testing took place for all oncoming personnel at the quarantine hotel, following the JRSO COVID-19 mitigation protocols. All scientists were cleared to board the vessel after receiving test results. Virtual orientation and preparation meetings continued, with the scientists receiving introductions to life at sea and science plans for the first two weeks of the expedition. Laboratory teams continued to work on their methods chapters and discuss their sampling and research plans for the expedition. The ship is scheduled to depart Cape Town on 12 April.
Preparations for offgoing freight continued and COVID-19 testing was conducted for offgoing personnel. The incoming shipment of cores from Expeditions 390C and 395E arrived and was loaded.
Daily Science Report for 7 April 2022
Location: Repair Quay 3, Cape Town, South Africa
Science Update: The South Atlantic Transect 1 Expedition 390 officially began in the port of Cape Town, South Africa, at 1154 h with the first line ashore. Port call activities included COVID-19 testing for departing personnel and loading of incoming freight, including the DMT core scanner.
All oncoming Expedition 390 personnel, including JRSO staff and the science party, continued to quarantine in a hotel in Cape Town as part of preboarding COVID-19 mitigation protocols. The seven-day hotel quarantine period, which includes two COVID-19 tests, will end on 9 April for most participants. Three members of the JRSO staff who arrived late will remain in the hotel for additional quarantine. On 9 April all other members of the JRSO staff and science party plan to board the JOIDES Resolution. During the hotel quarantine period, the Expedition 390 scientists began expedition preparation through a series of virtual meetings. These meetings included laboratory safety training, an introduction to IODP curation and publications services, coring and downhole logging operations, and presentation of individual research and shipboard outreach plans. Laboratory teams have begun meeting to discuss methods and shipboard sampling strategies. The ship is scheduled to depart Cape Town on 12 April.