IODP Expedition 398
Hellenic Arc Volcanic Field
Daily Science Report for 31 December 2022
Location: Site U1590 (proposed Site CSK-03A); 36°33.2939′N, 25°26.3881′E (preliminary); water depth 397 m (preliminary)
Science Update: Throughout the night and into morning of 31 December, work continued to free the drill string. At 0905 h, the drill string was severed at 526 mbsf and all remaining pipes were back on board at 1730 h. The 14.5 nmi transit to Site U1590 began at 1818 h, the vessel arrived on site at 1946 h, and Site U1590 officially started at 2020 h.
All laboratory groups worked on the site reports and site presentations throughout the day.
Daily Science Report for 30 December 2022
Location: Hole U1589C (proposed Site CSK-01A); 36°43.7463′N, 25°38.9046′E; water depth 482.6 m
Science Update: Throughout the night and morning of 30 December, work continued to free the triple combo. The triple combo was back on the rig floor at 1227 h. During retrieval operations, the drill string got stuck in the formation at 115.5 mbsf. Work on freeing the drill string continued throughout the day. Before the logging tools got stuck in the formation, the runs uphole and downhole produced a useable dataset that was sent for postprocessing to the Lamont Doherty Earth Observatory (LDEO). First inspection of the raw data indicates that several of the recorded downhole parameters are in good agreement with shipboard data.
All groups finished laboratory analyses on cores from Hole U1589 and worked on the site reports throughout the day.
In the early afternoon, the pre-site meeting for Site U1590 took place, including an overview of site objectives and updated seismic profiles.
Daily Science Report for 29 December 2022
Location: Hole U1589C (proposed Site CSK-01A); 36°43.7463′N, 25°38.9046′E; water depth 482.6 m
Science Update: Cores U1589C-26R to 28R were retrieved from 592.8 to 621.9 mbsf. The average recovery was 5% (2%–10%). Core U1589C-25R, recovered the previous day, already recovered a limestone pebble at its base. To be certain the hole reached basement, three more cores were drilled to a depth of 621.9 mbsf. Recovery was low, but all cores recovered limestone pebbles as well. With the recovery of Core 25R being 43% or 4.13 m, it was determined that the basement was reached within this core. Basement depth was set to ~589 mbsf. Following Core U1589C-28R, drilling in Hole U1589C was ended. In total, cores from Hole U1589C recovered 62.08 m of sediments, volcaniclastic rocks, and limestone basement, and reached a maximum depth of 621.9 mbsf. The drill string was tripped up to a depth of 66.5 mbsf. The hole was prepared for downhole logging, the triple combo—equipped with the Hostile Environment Natural Gamma Ray Sonde (HNGS), Hostile Environment Litho-Density Sonde (HLDS), High Resolution Laterolog Array (HRLA) tool for resistivity, and the Magnetic Susceptibility Sonde (MSS)—was assembled, and logging began at 1340 h. During the first logging run the tools encountered an obstruction at 544.9 mbsf that could not be passed. After a second logging run, the tool got stuck at 227.7 mbsf. The remainder of the day was spent retrieving the logging tools.
Core U1589C-25R was run through the whole-round physical properties track systems, and Cores U1589C-25R to 28R were split and described. The cores consist of matrix supported carbonate cemented breccia and limestone.
Daily Science Report for 28 December 2022
Location: Hole U1589C (proposed Site CSK-01A); 36°43.7463′N, 25°38.9046′E; water depth 482.6 m
Science Update: Cores U1589C-10R to 25R were retrieved from 445.8 to 592.8 mbsf. The average recovery was 25% (3% to 74%).
Cores U1589C-10R to 23R were run through the whole-round physical properties track systems. Core 24R only contained pebbles and was not logged. Cores U1589C-9R to 24R were split and described. The cores consist of clast supported conglomerates, gravelly sandstones, muddy sands, sandy muds, carbonate cemented sands, and carbonate cemented breccia.
Daily Science Report for 27 December 2022
Location: Hole U1589C (proposed Site CSK-01A); 36°43.7463′N, 25°38.9046′E; water depth 482.6 m
Science Update: Hole U1589C was drilled without recovery to 360 mbsf. Cores U1589C-2R to 10R were retrieved from 360 to 445.8 mbsf. The average recovery was 30% (0% to 74%).
Cores U1589C-2R to 9R were run through the whole-round physical properties track systems, and Cores U1589B-56F to 70F and U1589C-2R to 8R were split and described. The cores consist of greenish-gray nannofossil-rich muds, sands and silts layers of shells, and reddish-brown breccia and sandstones.
Daily Science Report for 26 December 2022
Location: Hole U1589C (proposed Site CSK-01A); 36°43.7569′N, 25°38.9053′E; water depth 482.6 m
Science Update: Cores U1589B-55F to 70F were retrieved from 288.2 to 359.4 mbsf. The average recovery was 80% (14% to 106%). At the base of Core 70F, the Sediment Temperature 2 (SET2) probe was deployed to analyze the formation temperature at the bottom of Hole U1589B. Following the SET2 deployment, Hole U1589B was ended. In total, coring at Hole U1589B recovered 331.46 m of sediments and volcaniclastic rocks, and reached a maximum depth of 381 mbsf. After completion, the drill string was tripped back up to the vessel. The BHA for rotary core barrel (RCB) coring was assembled and tripped back down to the mudline, spudding Hole U1589C in a water depth of 482.6 mbsl at 2304 h.
Cores U1589B-43F to 70F were run through the whole-round physical properties track systems, and Cores U1589B-27H to 56F were split and described. The cores consist of several nannofossil oozes, sapropel layers, and biotite bearing ashes. The sapropel layers often show a sharp lower contact to the oozes, with a gradual transition at the top. Geochemical analysis of pore water could confirm the salinity anomaly observed in Hole U1589A.
Daily Science Report for 25 December 2022
Location: Hole U1589B (proposed Site CSK-01A); 36°43.7574′N, 25°38.9057′E; water depth 482.6 m
Science Update: Cores U1589B-13F to 54F were retrieved from 96.2 to 288.2 mbsf. The average recovery was 94% (26% to 110%). Cores U1589B-11H to 43F were run through the whole-round physical properties track systems, and Cores U1589B-3H to 27H were split and described. The cores consist of prominent ash layers, lapilli pumice, sapropels, and nannofossil oozes.
Daily Science Report for 24 December 2022
Location: Hole U1589B (proposed Site CSK-01A); 36°43.7574′N, 25°38.9057′E; water depth 482.6 m
Science Update: Cores U1589A-75X to 76X were retrieved from 436.2 to 446.7 mbsf. The average recovery was 84%, ranging between 0% and 107%. Downhole advancement had slowed to ~2 m/h and it was decided to end Hole U1589A. In total, Hole U1589A recovered 360.47 m of sediments and volcaniclastic rocks and reached a maximum depth of 446.7 mbsf. Pulling the drill string up to the mudline, the ship moved 20 m toward the east to spud Hole U1589B. Cores U1589B-1H to 12H were retrieved from 0 to 96.2 mbsf. The fireplace and tree were set up in the conference room and the stockings were hung in the galley with care.
Cores U1589A-69X to 76X and U1589B-1H to 10H were run through the whole-round physical properties track systems, and Cores U1589A-50F to 76X and U1589B-1H to 2H were split and described. The cores consist of bioturbated nannofossil oozes, ash layers, several sapropel layers, prominent rip-up clasts, few microfaults, reddish brown matrix-supported breccia, and contained clasts of metamorphic basement. Microscopic analysis of smear slides showed high, glass, foraminifers and calcareous nannofossils, as well as metamorphic minerals such as glaucophane and actinolite.
Daily Science Report for 23 December 2022
Location: Hole U1589A (proposed Site CSK-01A); 36°43.7577′N, 25°38.8915′E; water depth 484.3 m
Science Update: Cores U1589A-50F to 65F were retrieved from 290.3 to 365.5 mbsf. The average recovery was 84%, ranging between 0% and 107%. Core 55F misfired and had no recovery. Beginning at Core 65F, the formation became so stiff that the core could not be pulled out but had to be drilled over to retrieve it. Thus, beginning at Core 66X, operations were changed to XCB coring. Cores U1589A-66X to 74X were retrieved from 365.5 to 436.2 mbsf with an average recovery of 35% (ranging from 1% to 77%). Core 66X had a low recovery of 15% as the pump pressure might have been too high, washing away softer lithologies. An adjustment in pump pressure resulted in considerably higher recovery of 77% and 72% in the following cores. Beginning at Core 72X, the formation became so hard that cores were advanced based on time instead of core barrel length.
Cores U1589A-38F to 68X were run through the whole-round physical properties track systems, and Cores 22F to 50F were split and described. The cores consist of bioturbated nannofossil oozes, ash layers, several sapropel layers, and contained clasts of metamorphic basement. Microscopic analysis of smear slides showed high amounts of foraminifers and calcareous nannofossils, as well as metamorphic minerals such as glauconite, glaucophane, and actinolite. Geochemical analyses of IW indicated a very high salinity in one core that clearly deviates from average salinities of nearby cores.
Daily Science Report for 22 December 2022
Location: Hole U1589A (proposed Site CSK-01A); 36°43.7577′N, 25°38.8915′E; water depth 484.3 m
Science Update: Cores U1589A-13H to 15H were retrieved from 106.7 to 135.2 mbsf. The average recovery was 36%, ranging between 4% and 99%. Core 13H suffered from damaged outer seals, resulting in a recovery of 5%. The following core, 14H, misfired and retrieved 34 cm or 4%. While penetration was still good for Core 15H, the pulling resistance increased to a level that made it necessary to drill over the APC barrel in order to recover it. Thus, beginning at Core 16F, operations were changed to half-length advanced piston corer (HLAPC) coring. Cores U1589A-16F to 49F were retrieved from 135.2 to 290.3 mbsf with an average recovery of 96% (ranging from 5% to 108%). Core 39G misfired, resulting in a so-called ghost core. These cores recover sediment without knowledge about the depth these sediments were recovered from. Thus, Core 39G will not be analyzed and is now designated as a training core for future expeditions and educational purposes.
Cores U1589A-9H to 37F were run through the whole-round physical properties track systems, and Cores 4H to 22F were split and described. The cores consist of centimeter to meter-scale layers of coarse pumice lapilli and water saturated ash layers, laminated muds, thin (sometimes bioturbated) layers of fine ash, tuffaceous muds, volcaniclastic layers with lapilli sized clasts, hemipelagic sediments, and one sapropel layer in Core 8H. Microscopic analysis of smear slides showed high amounts of volcanic glass, ash, foraminifers, and calcareous nannofossils. Shear strength analyses throughout the hole show a high variability that correlates to sediment composition, with higher shear strength in mud layers and low to very low values in units of sandy ash and pumice lapilli. Geochemical analyses of interstitial water (IW) show a progressive decrease in alkalinity with increasing depth.
Daily Science Report for 21 December 2022
Location: Hole U1589A (proposed Site CSK-01A); 36°43.7577′N, 25°38.8915′E; water depth 484.3 m
Science Update: The ship completed the 1241 nmi voyage from Tarragona, Spain, to Site U1589 in the Greek Aegean Sea near the islands of Anhydros, Amorgos, and Ios on 21 December at 0715 h. The thrusters were lowered, and the drill string was being assembled, consisting of a 5 inch drill pipe and an advanced piston corer/extended core barrel (APC/XCB) bottom-hole assembly (BHA). We installed the sinker bars and the Icefield MI-5 orientation tool and positioned the drill bit at 452.1 meters below rig floor (mbrf). Coring in Hole U1589A started at 1435 h with Core U1589A-1H recovering 2.18 m (99%) and establishing a seafloor depth at 484.3 meters below sea level (mbsl). APC coring continued with Cores U1589A-1H through 12H, penetrating the seafloor to 106.7 meters below seafloor (mbsf), with an average recovery of 90% (ranging from 24% to 105%). Core 5H experienced a minor problem with its lock-pins that resulted in about 30 min of work on the rig floor. During this time, the sediments partially liquified, resulting in a recovery of 24%.
Cores U1589A-1H to 8H were run through the whole-round physical properties track systems, and Cores 1H to 3H were split and described. The cores consist of tuffaceous muds, volcaniclastic layers with lapilli sized clasts, beds of pumice, and hemipelagic sediments. The base of Core 6H is estimated to be of Holocene to Pleistocene age (<0.265 Ma). Microscopic analysis of smear slides showed high amounts of volcanic glass, pyroxene crystals, authigenic calcite, volcaniclastics, sponge spicules, foraminifers, and calcareous nannofossils.
Daily Science Report for 20 December 2022
Location: Underway to Site U1589 (proposed Site CSK-01A); midnight location 36°17.64′N, 24°13.45′E
Science Update: Laboratory training continued throughout the day. The day and night shifts received individual training sessions using the IODP Sample Master software. Laboratory training and practice continued for all working groups. The core description group finalized most of their GEODESC templates with assistance from staff onshore. At 1300 h the pre-site meeting for Site U1589 took place, including information on the operations plan, site objectives, and regional geology. Following this meeting was a short presentation on regional seismic interpretations and an overview of IODP depth scales. In the late afternoon, the paleomagnetists, the Outreach Officer, and the EPM conducted a test that evaluated the impact of the Outreach Officer tablet’s WiFi on the paleomagnetometer. The magnetometer is very sensitive to electromagnetic signals and the result showed that there is no immediate interference with the tablet’s WiFi and the magnetometer. Reviews and revisions of the methods chapters continued.
At the end of the day, the ship had completed 1162.4 nmi of the 1241 nmi transit. The ship is scheduled to arrive at Site U1589 in the Anhydros Basin in the morning of 21 December.
Daily Science Report for 19 December 2022
Location: Underway to Site U1589 (proposed Site CSK-01A); midnight location 36°08.30′N 19°53.72′E
Science Update: All scientists and JRSO staff members conducted self-administered antigen tests at the beginning of their shift. Laboratory setup continued throughout the day. The ship’s clocks were moved forward one hour at 0200 h, and the vessel is now UTC + 2 h. At the end of the day, the ship had completed 950.4 nmi of the 1241 nmi transit.
The Geochemistry Laboratory group and technicians met with the Co-Chief Scientists and the EPM to discuss the process of switching between fluid and hard rock sample measurements. Both core description shifts conducted “dry runs” that included practicing core descriptions on high-definition core photos and running the core loggers with training cores. Laboratory training and familiarization continued for all working groups. Reviews and revisions of the methods chapters continued. In accordance with expedition permits, the ship sent out the daily operations update to the Greek authorities. All scientists, staff, and crew members continued to follow COPE protocols until 1810 h. At this time, the COPE mitigation period came to its official conclusion as all scientists, JRSO staff, and crew members tested negative for SARS-CoV2 every day since 11 December.
The ship is scheduled to arrive at Site U1589 in the Anhydros Basin in the early morning of 21 December.
Daily Science Report for 18 December 2022
Location: Underway to Site U1589 (proposed site CSK-01A); midnight location 36°20.15′N, 14°43.00′E
Science Update: All scientists and JRSO staff members conducted self-administered antigen tests at the beginning of their shift.
Laboratory setup continued throughout the day. The Marine Computer Specialists performed updates on all PCs during the day and used the night from 18 to 19 December for work on the ship’s servers that resulted in a scheduled downtime during the maintenance period. At the end of the day, the ship had completed 699.4 nmi of the 1241 nmi transit.
The core description team received individual training sessions on the Section Half Imaging Logger (SHIL) and the Section Half Multisensor Logger (SHMSL). The Operations Superintendent gave rig floor and coring tool introductions to all of the science party members. The Expedition 398 Sample Allocation Committee (SAC) met in the early afternoon to discuss the sampling strategy for Site U1589 and approved the sample requests of two shore-based scientists. Following the SAC meeting, the Co-Chief Scientists, Operations Superintendent, and EPM met for a pre-spud meeting. The main objectives of the meeting were the discussion of site-specific drilling requirements and the operations plan for downhole temperature probes using the advanced piston corer temperature (APCT-3) and Sediment Temperature 2 (SET2) tools. Reviews and revisions of the methods chapters continued. In accordance with expedition permits, the ship sent out the daily operations update to the Greek authorities. All scientists, staff, and crew members continue to follow COPE protocols. The ship is scheduled to arrive at Site U1589 in the Anhydros Basin in the morning of 21 December.
Daily Science Report for 17 December 2022
Location: Underway to Site U1589 (proposed Site CSK-01A); midnight location 38°28.34′N 9°18.40′E
Science Update: All scientists and JRSO staff members conducted self-administered antigen tests at the beginning of their shift. As the weather conditions are very favorable, extensive rig floor preparations are being made. Throughout the day, the laboratories were being set up and the Marine Computer Specialists conducted the monthly operating system updates on the ship’s Linux servers. At the end of the day, the ship had completed 406 nmi of the 1241 nmi transit.
In the early morning, the physical properties night shift received an introduction to the shipboard logging tracks and started their training with these systems throughout their shift. Both Co-Chief Scientists and the EPM attended a rig floor tour and introduction into coring equipment led by the Operations Superintendent. Throughout the day, reviews and revisions of the methods chapters continued. In accordance with expedition permits, the ship sent out a 72 h operational notice to the Greek authorities. All scientists, staff, and crew members continue to follow COPE protocols. The ship is scheduled to arrive at Site U1589 in the Anhydros Basin in the early morning of 21 December.
Daily Science Report for 16 December 2022
Location: Underway to Site U1589 (proposed Site CSK-01A); midnight location 40°20.27′N, 3°45.61′E
Science Update: Bunkering of 1200 mt fuel continued throughout the night, concluding at 0400 h. Port call activities continued with the delivery of two engine oil filters at 1130 h and securing the vessel for sea passage. All scientists and JRSO staff members conducted self-administered antigen tests at the beginning of their shift. With the pilot aboard the vessel at 1237 h, the ship cleared the last line and departed the pier in Tarragona at 1254 h. Tugboats released the vessel at 1302 h and the pilot departed at 1306 h. At the end of the day, the ship had completed 126 nmi of the 1241 nmi transit.
In the afternoon, the core description day shift received GEODESC training. The physical properties day shift received an introduction into the shipboard logging tracks and started their training with these systems in the early evening. Throughout the day, work on methods chapters continued with the first draft versions being sent to the Science Office for review. All scientists, staff, and crew members continue to follow COPE protocols. The ship is scheduled to arrive at Site U1589 in the Anhydros Basin in the early morning of 21 December.
Daily Science Report for 15 December 2022
Location: Muelle de Baleares, Tarragona, Spain
Science Update: Port call activities continued with final food deliveries and the boarding of two crew members. Bunkering of 1200 mt of fuel began in the evening and continued throughout the night. At the beginning of their shifts, all scientists and JRSO staff conducted a self-administered rapid antigen test, supervised by the Laboratory Officers and Expedition Project Manager (EPM). At 1030 h, all scientists and new JRSO staff participated in a lifeboat emergency drill.
In the early morning, laboratory and ship safety orientation tours continued. Throughout the day laboratory familiarization and work on methods chapters continued. In the afternoon, the Operations Superintendent, EPM, and one of the Greek observers met with the ship’s leadership to discuss permits and compliance procedures. The ship is scheduled to depart Tarragona in the early afternoon of 16 December.
Daily Science Report for 14 December 2022
Location: Muelle de Baleares, Tarragona, Spain
Science Update: Port Call activities continued with the loading of two core liner boxes and other freight as well as the successful repair and subsequent load-testing of crane #3. Beginning at 1300 h, all scientists, JRSO staff, and ship’s crew underwent another PCR test.
Led by the Laboratory Officer (LO), several smaller groups of scientists received core flow orientation tours in the morning. In the afternoon and throughout the night, all scientists received laboratory and ship safety orientations. Work on the methods chapters continued throughout the day. Shipboard COVID-19 mitigation protocols (COPE) are being followed and the ship is scheduled to depart Tarragona on 16 December.
Daily Science Report for 13 December 2022
Location: Muelle de Baleares, Tarragona, Spain
Science Update: Port Call activities continued with loading and offloading of freight, and the departure of the last Expedition 397 JRSO staff. In the morning, all Expedition 398 scientists and JRSO staff tested negative for COVID-19 and were subsequently released from the hotel quarantine. JRSO staff members boarded the JOIDES Resolution in Tarragona at approximately 1145 h and the science party boarded at 1300 h. Following a temperature check, all scientists boarded in smaller groups, adhering to the COPE protocol. Throughout the day all scientists familiarized themselves with the ship and its laboratories, set up their computers, and spent their shift working on the methods chapters of their respective laboratories.
The ship is scheduled to depart Tarragona in the morning of 16 December.
Daily Science Report for 12 December 2022
Location: Muelle de Baleares, Tarragona, Spain
Science Update: Port Call activities continued with loading and offloading of freight. The Expedition 397 science party and some of the JRSO staff departed the vessel.
All Expedition 398 scientists, JRSO staff, and the ship’s crew continued their hotel quarantine in their hotels in Barcelona and Tarragona, Spain. In the morning, a SARS-CoV2 Antigen test was conducted with results arriving around noon. All participants tested negative for the virus in today’s antigen as well as yesterday’s PCR test.
Virtual science meetings and orientation continued with instructions on life at sea and safety, coring and curation, and publications for the science party and new JRSO staff.
The scientific meetings focused on anticipated lithologies as well as templates for the core description application GEODESC, followed by Expedition 398 outreach, and final boarding instructions.
The ship is scheduled to depart Tarragona on 16 December.
Daily Science Report for 11 December 2022
Location: Muelle de Baleares, Tarragona, Spain
Science Update: IODP Expedition 398, Hellenic Arc Volcanic Field, officially began in Tarragona, Spain, at 0736 h on 11 December 2022 upon arrival of the JOIDES Resolution at the end of Expedition 397. Port call activities began with the arrival of oncoming shipments and offloading freight. In addition to logistic activities, two visitors from the National Science Foundation (NSF) visited the ship.
Expedition 398 will be working in the active volcanic center of the Christiana, Santorini, and Kolumbo volcanoes in the Hellenic Arc of the Aegean Sea. The expedition will investigate this volcanic center, including two drill sites in the Santorini caldera which collapsed as a result of volcanic explosions, and its associated marine basins of Anhydros and Anafi. Drilling these locations will provide a rich record of volcanic activity much older than that known on land, extending the knowledge of eruptive history back from ~650,000 years ago to about 3 Ma or older. Assessing the potential for future eruptive events, and the likelihood for the generation of eruption-associated tsunamis, could assist in mitigating any threat to these islands that have a year-round population and more than 2 million visitors per year. These records will also reveal a history of regional sea level change and how life deep within the sediments responds to volcanic activity.
All oncoming Expedition 398 personnel, including JRSO staff and scientists, arrived two to three days earlier in Barcelona to follow a four-day hotel quarantine. The quarantine includes PCR and antigen tests, according to the COVID-19 mitigation COPE protocol. The Expedition 398 scientists and the JRSO technical staff kicked off the expedition in the morning of 10 December with virtual scientific presentations and preboarding orientations. The meetings included several discussions of the scientific expedition objectives with a focus on 1) Correlations, 2) Petrology and Geochemistry, and 3) Minoan Eruption and Hazards. IODP orientations included onboard computing as well as a presentation by the Operations Superintendent on coring and downhole logging operations. All laboratory groups began to discuss their specific shipboard methods.
The hotel quarantine will continue until 13 December, when all expedition members will depart Barcelona for Tarragona and the JOIDES Resolution.