IODP Expedition 350

Izu-Bonin-Mariana Rear Arc

Daily Science Report for 30 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

Lowering of the 16 inch casing string continued from 1105 m below rig floor (mbrf) until it arrived near the seafloor (2120 mbrf) at 0145 h. The camera system was deployed to guide the reentry into Hole U1437E, which was completed at 0350 h. The casing was lowered into the hole to 2351 mbrf by tripping pipe. At that point, the top drive was engaged to facilitate further lowering of the casing down to 2391.1 mbrf. The top of the casing was latched into the casing hanger in the reentry cone at 0600 h, and the latch was verified with 10 klb of pull from the rig. To ensure the casing will indeed act as the circulation conduit during future coring in Hole U1437E, the bottom of the casing had to be cemented firmly to the formation. Twenty barrels of 14.5 lb/gal cement were pumped from the rig floor through the drill string and the 60 m stinger extending from the casing running tool down into the hole; the casing running tool formed a seal at the top of the 16 inch casing. The cement emplacement was followed up with 295.8 barrels of seawater, a volume calculated to displace the cement to the bottom of the casing such that half the cement volume would extended between the formation and the casing, and the other half would remain near the bottom and inside the casing, to be drilled out later. The cement was in place at 0720 h. The casing running tool was released and the drill string and standpipe manifold were flushed clean with seawater. The camera was retrieved and the top drive disengaged to ready the rig for tripping pipe. The drill string was retrieved, and the running tool cleared the rig floor at 1220 h. After breaking down the running tool and the underreamer assembly, a bottom-hole assembly with a 14.75 inch tricone drill bit was installed and the drill string was tripped back to the seafloor. The camera was deployed to guide the reentry into Hole U1437E, completed at 2245 h, then was retrieved back to the rig floor. By 2400 h, the drill string was ready to be lowered to the bottom of the hole.

Scientists continued to draft, edit, and finalize reports, and convened for a seminar talk entitled “Composition of the slab-derived fluids released beneath the Mariana forearc: evidence for shallow dehydration of the subducting plate.” A “hump-day” celebration around midnight was attended by scientists, technical staff and crew members.

Daily Science Report for 29 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

Hole U1437E was advanced to the target depth (271.7 mbsf) for installing the 16 inch casing by 0400 h. The hole was swept with 60 barrels of high-viscosity mud to remove drill cuttings. The drill string was then raised to 12.7 mbsf and lowered back down to total depth (271.7 mbsf) while circulating seawater to ensure the borehole was clear. No obstruction or fill at the bottom of the hole was detected. Another 60 barrel high-viscosity mud sweep was circulated. The drill string was pulled out of the hole with the bit clearing the seafloor at 0910 h and arriving at the rig floor at 1300 h. The 16 inch casing was assembled in an eight-hour effort. The casing running tool was installed and the trip to the seafloor began, advancing to 1105 m below the rig floor by midnight. Scientists continued to draft, edit, and finalize reports, and convened for a seminar talk entitled “Unravelling the crustal architecture of Cape Verde; the xenolith record.”

Daily Science Report for 28 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

After the drill string was retrieved back on the rig floor, it was equipped with a bit and underreamer to drill the hole for the 264 m‑long, 16 inch casing. The drill string was deployed to the seafloor, followed by deployment of the subsea camera to observe the reentry into Hole U1437E. After the successful reentry, the camera system was retrieved and drilling in Hole U1437E had reached 226 mbsf by the end of the day. Scientists continued to finalize site reports and convened for a seminar talk on the “Geochemistry of volcanic glasses drilled from the Louisville seamounts (IODP Expedition 330): implications for eruption environments and mantle melting.”

Daily Science Report for 27 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

The ship moved ~20 m northeast to begin installation of casing in Hole U1437E. The reentry cone, equipped with 20.7 m of 20 inch casing, was run to the seafloor. The subsea camera system was deployed to observe the jetting in of the casing and landing of the reentry cone on the seafloor. Deployment was complete at 1905 h, the drill bit cleared the reentry cone, and the camera system and drill string were retrieved. Scientists continued to finalize Site U1436 reports and prepare drafts of the Site U1437 reports.

Daily Science Report for 26 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Cores U1437D-69R through ‑73R (1056.1–1104.6 m) recovered 22.7 m (47% recovery) of polymictic, evolved lapilli-tuff and lapillistone (total of 8.8 m, average thickness 0.4 m), evolved tuff (total of 4.8 m, average 0.2 m) and now subordinate tuffaceous mudstone (total of 1.4 m, average 0.1 m). Sections U1437D-69R-1 through 71R-2 contained solid rock cylinders of typically 0.1 to 0.8 m length. Starting with Section U1437D-71-3 the cores were fractured and shattered into granule to cobble size pieces and recovery decreased from 96% in Core U1437D-70R to 19% in Core U1437D-73R. The crushed rock is of the same composition as the solid pieces above. Shape of fractures and clasts indicate a drilling induced destruction of the rock rather than a fault zone.

An unusually large quantity of mud was needed to clean Hole U1437D of the crushed material in the interval 1076–1105 m (Cores U1437D-71R through ‑73R). Furthermore, drilling mud was found packed around the bottom of the core barrel on the last three wireline runs, indicating a problem with the seating of the core barrel that is likely related to the crushing and non-recovery of the rock. Therefore, the decision was made to retrieve the drill string. During the initial retrieval, a blockage at the bottom of the string was indicated by the water level in the drill pipe each time a stand of pipe was removed at the rig floor. Symptoms of that blockage disappeared later.

Given that the risk of not being able to clean out an uncased hole increases with penetration depth (whether related to formation or mechanical issues), and that we have a maximum of ~1090 m of casing on the ship (about the current total depth of Hole U1437D), we decided to terminate Hole U1437D and start a new cased hole to be able to core and log deeper. We plan to offset the ship ~20 m to the east, drill and case Hole U1437E to the current total depth, then continue to core until time expires. The casing plan includes a reentry cone with 20 inch casing to 20 m, 16 inch casing to ~264 m (cemented at bottom), and 10.75 inch casing to ~1090 m (also cemented at bottom). Casing operations are estimated to take 1.5–2 weeks. If all goes well, we should be able to core another several hundred meters, approaching a total cored interval of 2 km.

Daily Science Report for 25 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Cores U1437D-62R through ‑68R (998.3–1056.1 m) recovered 31.0 m (54% recovery) of evolved tuff, clast-supported polymictic lapilli-tuff, and tuffaceous mudstone. While average thickness of mudstone layers has remained at ~0.2 m downhole, the tuff layer average has increased to ~0.3 m in this interval (maximum increased from 1.0 to 1.5 m), and the lapilli-tuff layers average ~0.4 m in thickness. The thickness ratio of tuff and lapilli-tuff vs. mudstone has increased to 2:1.

Daily Science Report for 24 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: After the drill string was tripped back to the surface and a rotary coring bit was installed, the drill string was again deployed to the seafloor and re-entered Hole U1437D to continue RCB coring. Cores U1437D-60R and ‑61R (980.4–998.3 m) recovered 15.6 m (87% recovery) of evolved tuff, with minor lapilli-tuff, and tuffaceous mudstone. The bioturbated mudstone and tuff layers range in thickness from 0.1 to 1 m and average 0.2 m. The thickness ratio of mudstone to tuff is ~1:1. Two biostratigraphic datums were constrained at 874 m (<5.3 Ma) and 998 m (<7.4 Ma). Cores U1437D-37R through ‑51R were sampled for postcruise studies.

Daily Science Report for 23 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: After the first logging run with the triple combo-MSS tool string was successfully completed from ~960 m to 92 m, the Formation MicroScanner and Sonic (FMS-sonic) tool string was made up and lowered to ~930 m, where hole fill was detected. The FMS-sonic log was also completed successfully. The third and last logging run was the vertical seismic profile (VSP), which allowed us to establish the depths of the seismic reflectors within the logged interval at Site U1437. All downhole logs are of excellent quality due to the favorable hole conditions. The drill string was tripped back to the surface and a rotary coring bit was installed. The plan is to re-enter Hole U1437D and continue RCB coring.

Daily Science Report for 22 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: After the failure to re-enter Hole U1437D with the top connector of the mechanical bit release (MBR) at the bottom of the drill string, the drill string was retrieved and the MBR top connector was replaced with a logging bit. In contrast to the razor sharp edges of the MBR top connector, the logging bit has a rounded “bull nose” face and therefore the best chances to re-enter a hole smoothly. The drill string was tripped back to the seafloor, entered Hole U1437D without incident, and the bit was positioned at ~92.4 m, ready for logging. Wireline logging began with the deployment of the “triple combo” tool string combined with the Magnetic Susceptibility Sonde (MSS). The triple combo measures natural gamma radiation, resistivity, bulk density, and porosity. The triple combo-MSS string was successfully lowered to ~960 m (20 m off bottom of hole) and the first logging run was completed in good hole conditions.

Daily Science Report for 21 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Cores U1437D-56R through ‑59R (941.6–980.4 m) recovered 33.6 m (87% recovery) of evolved tuff and lapilli-tuff, intercalated with tuffaceous mudstone. The total thickness ratio of tuff to mudstone is ~2:1. The tuff layers are generally green and silicified, often displaying spectacular “marble-like” appearances. Some coarser-grained layers are gray to black and display parallel and cross bedding. No biostratigraphic age constraints are available for these cores. The last fully reliable age indicator was in Core U1437D-40R (805.8 m; 4.6 Ma). After these cores were recovered, we began preparations to conduct wireline logging.

Our first step was to assemble a free-fall funnel around the drill string at the rig floor and drop it to the seafloor. The drill string was then pulled out of the hole, the ship moved ~40 m east, and the RCB was released from the drill string onto the seafloor. When the ship returned to the free-fall funnel to re-enter Hole U1437D, the end of the drill string struck the inside of the funnel, which triggered a billowing cloud of drilling mud and cuttings that eliminated the necessary visibility for reentry. We decided to retrieve the drill string to let the cloud settle and to install a logging bit. In contrast to the open end of the drill string, the logging bit has a smoother profile to facilitate reentry and provides increased drilling capabilities that might increase chances of being able to log the hole successfully. In the meantime, scientists prepared for sampling Cores U1437D-24R through ‑37R for postcruise studies.

Daily Science Report for 20 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Cores U1437D-49R through ‑55R (873.7–941.6 m) recovered 64.8 m (95% recovery) of tuffaceous mudstone intercalated with white, gray and dark gray layers of silicified evolved tuff. Green (chloritic?) alteration is pervasive. No biostratigraphic age constraints are available for these cores. The last fully reliable age indicator was in Core U1437D-40R (805.8 m; 4.6 Ma). We completed the fourth concerted sampling effort for postcruise studies for Cores U1437D-2R through ‑23R.

Daily Science Report for 19 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Cores U1437D-39R through ‑48R (786.3–873.7 m) recovered 65.0 m (74% recovery) of tuffaceous mudstone intercalated with evolved tuff (with crystals) layers. The cores are generally dark green and dark gray due to significant alteration. After splitting the cores, oxidation changes the color of some intervals from bright green to dark gray in a matter of minutes to hours. The age of Cores U1437D-42R through ‑44R was constrained by biostratigraphy to 11.8–12.8 Ma. The last sample dated above this interval is Section U1437D-19R-CC (601 m; 3.7 Ma). No microfossils have yet been observed in cores below 845 m. Cores U1437D-2R through ‑23R were laid out across labs and conference room for the fourth sampling party.

Daily Science Report for 18 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Cores U1437D-25R through ‑38R (650.4–786.3 m) recovered 99.7 m (73% recovery) of volcaniclastic sediment. Cores U1437D-25R through ‑27R consist predominantly of tuffaceous mudstone with intercalated dark gray, sometimes cross-stratified, evolved tuff layers. In Core U1437D-28R, light gray layers of silicified lapilli-tuff and distinctly parallel and cross-stratified tuff layers appear. The light gray layers of clast-supported monomictic evolved lapilli-tuff, lapillistone and tuff layers dominate Cores U1437D-29R and ‑30R, and make up about half of Cores U1437D-31R and ‑32R. Cores U1437D-33R and ‑34R are dominated by (evolved) tuff (with mudstone) and (tuffaceous) mudstone, and the coarser layers become a minor component. One ~2 m-thick interval in Core U1437D-34R includes tuff-breccia and is interpreted as a debris flow deposit. The change to coarser-grained volcaniclastic sediment at ~690 m presumably corresponds to the seismic stratigraphic boundary between Layer 3 and Layer 4. The age of the 136 m-thick interval recovered is between 4 and 6 Ma based on biostratigraphic datums. Preparations are underway to lay out and sample Cores U1437D-2R through ‑23R (sampling party #4).

Daily Science Report for 17 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Cores U1437D-6R through ‑24R (466.0–650.4 m) recovered 148.3 m (80% recovery) of predominantly tuffaceous mudstone with intercalated darker colored tuff layers. The mudstone intervals consist of mudstone, tuffaceous mudstone, tuffaceous mafic mudstone, or tuffaceous evolved mudstone. The tuff layers are predominantly evolved tuff, with intervals of evolved lapilli-tuff, bimodal tuff, and crystal-bearing tuff layers. The age of this interval is between 2.8 and 3.5 Ma based on biostratigraphic datums. A change to predominantly coarser-grained volcaniclastic sediment of presumably pre-Pliocene age is expected in the next 1–2 days based on seismic stratigraphy. In addition to measuring and describing recovered cores, scientists worked on the reports for Site U1436.

Daily Science Report for 16 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Drilling without coring in Hole U1437D continued to 427.2 m, 8.1 m above the total depth cored in Hole U1437B. Multiple mud sweeps were applied, particularly near 300 m where the drill string became stuck in Hole U1437C, to avoid drilling problems. The center bit was pulled via wireline trip and a core barrel was deployed, delivering the first RCB core on deck at 1915 h. Cores U1437D-2R through ‑5R (427.2–466.0 m) recovered 23.4 m (60% recovery) of predominantly mudstone (with lapilli, with tuff) intercalated with mafic, evolved or bimodal tuff layers with thicknesses on the order of 10 cm and an average frequency on the order of 1 m. The age of this interval is between 2.8 and 3.5 Ma based on biostratigraphic datums. The precruise age estimate for this depth was ~6.5 Ma. The bottom of this seismic unit is expected at ~830 m, where the borehole should penetrate more local volcanic deposits. Scientists and technical support staff completed the third sampling party, for the lower part of Hole U1437B.

Daily Science Report for 15 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: At 0100 h, the drill string became stuck at ~300 m in Hole U1437C. We had been drilling ahead without coring with the RCB system and were going to start RCB coring just above the total depth that XCB coring reached in Hole U1437B (439 m; located just 20 m to the north). We had to drop the drill bit to free the drill string from the formation. The drill string was retrieved, a new bit release and bit installed, the ship moved ~20 m to the northwest, and the bit lowered to the seafloor. We resumed drilling in Hole U1437D at 2250 h. We plan to drill to ~425 m and start RCB coring from that depth. Shipboard scientists prepared for a third sampling party, for the lower part of Hole U1437B.

Daily Science Report for 14 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Coring in Hole U1437B was concluded at 0000 h. The drill string was pulled from the hole and to the rig floor to remove the APC/XCB coring system and install the RCB system. The vessel moved 20 m South of Hole U1437B and the drill string was lowered to the seafloor. Drilling in Hole U1437C began without coring, with a target depth of ~400 m where coring is to resume. The science party, with support from the technical staff, began sampling the Hole U1437B cores, which were laid out across the core lab, downhole lab, and conference room.

Daily Science Report for 13 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Cores U1437B-36X through ‑55X (252.3–439.1 m) recovered 45.5 m of sediment from the 186.8 m interval cored (24% recovery). This concluded operations in Hole U1437B. As with the overlying cores in Hole U1437B, the material cored in this interval consists predominantly of mud and mud with ash, intercalated with mafic and evolved ash (with mud). Over the entire section recovered in Hole U1437B, the ash layers range from 0.01 to 1.5 m in thickness (average 0.08 m) and the ash layer to mud layer ratio is 1:7. The base of Hole U1437B has an age between 2.8 and 3.5 Ma based on biostratigraphic datums. A sampling party for Hole U1437B is in preparation.

Daily Science Report for 12 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Cores U1437B-10H through ‑35X (79.7–252.3 m) recovered 117.8 m of sediment from the 172.6 m interval cored (68% recovery). Recovery was nearly complete (99%) for the piston cored section (79.7–145.7 m), however, the rate of penetration decreased exponentially towards the bottom of that interval. We therefore switched to the XCB coring system with Core U1437B-25X. Recovery dropped dramatically to 48% in the XCB cored interval. The material cored today consists predominantly of mud, mud with ash or ash pods, and mafic or evolved ash with mud. This muddy facies is intercalated with up to ~5 ash layers per meter. The ash layers are typically 1–10 cm thick, graded, frequently bioturbated at their lower and upper boundaries, and of mafic, evolved or bimodal composition, occasionally containing discernible crystals. Rare layers of clay, tuffaceous ash, and mud with lapilli also occur. The interval cored has an age of ~0.6 to ~0.9 Ma based on biostratigraphic datums.

Daily Science Report for 11 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Deployment of the drill string at Site U1437 was completed in the early morning. The first Hole U1437A consisted of a jet-in test to 25 m to assess the sub-seafloor for future casing operations at this site. The jet-in test was followed by coring in Hole U1437B, with Cores U1437A-1H through ‑9H (0–79.7 m) retrieving 79.3 m of sediment (99% recovery). The material consists predominantly of mud with ash, or less commonly clay with ash pods. The mud is intercalated with typically 1–3 thin layers per meter of evolved ash or mafic ash, in some cases with discernible crystals. Only very few layers of lapilli ash or ash with lapilli were observed. The interval cored yielded all biostratigraphic age indicators from recent to 0.61 Ma.

Daily Science Report for 10 April 2014

LOCATION: Site U1437 (31°47.39′N, 139°01.58′E)

SCIENCE UPDATE: Coring in Hole U1436A was completed in the early morning with Cores U1436A-16X though ‑21X (92.8–150.0 m) with a recovery of 12%. Total recovery in Hole U1436A was 48%. This completed drilling operations at Site U1436. The recovered intervals in this lower part of Hole U1436A consist of intercalated layers of mud with mafic or evolved ash, mafic or evolved ash with or without mud, a layer each of evolved ash breccia with mud, clast-supported polymictic, mafic lapilli, and evolved lapilli ash. Biostratigraphic and magnetostratigraphic data indicate a late Pleistocene age. The drill pipe was recovered and the vessel departed Site U1436 at 1330 h. After a 7.5 h transit to Site U1437 (proposed site IBM-3C) the crew began tripping the drill sting to the seafloor.

Daily Science Report for 9 April 2014

LOCATION: Site U1436 (32°23.8854′N, 140°21.9288′E)

SCIENCE UPDATE: The camera survey of the seafloor around Site U1436 was completed in the early morning and coring could begin. Core U1436A-1H arrived on deck at 0725 h. Cores U1436A-1H through ‑7H each recovered between 5.7 and 9.0 m of late Pleistocene (<0.7 Ma) intercalated layers of mud or silt with ash, evolved or mafic ash, and matrix or clast-supported monomictic or polymictic evolved or mafic ash with variable amounts of lapilli or pumice. Recovery decreased below that interval, presumably as a result of increasing ash or decreasing mud content. We decided to deploy the half-length (4.7 m) advanced piston corer (HLAPC) to increase recovery. However, Cores U1436A-10F through ‑12F only yielded 2.5 to 0.5 m recovery each. The material consisted predominantly of ash that easily formed a slurry in the core liner. Given the diminishing return and slow rate of penetration with the HLAPC, we deployed the XCB system. Cores U1436A-13X through ‑15X only yielded 0.4 m of core from a 27.8 m interval. Recovery over the entire interval cored in Hole U1436 (0–92.8 m) was 70%.

Daily Science Report for 8 April 2014

LOCATION: Site U1436 (32°23.8854′N, 140°21.9288′E)

SCIENCE UPDATE: The vessel arrived at Site U1436, the first site of Expedition 350, at 1142 h. The drill string was made up and lowered to the seafloor. The rest of the day was spent carrying out a camera survey of the seafloor around Site U1436 to verify that no submarine communications cable are present. The shipboard science party received two seminar talks entitled “The igneous geochemistry of likely Neogene volcanic materials at our drill site: implications for mantle evolution from a subduction zone to a spreading center” and “Linking seismic velocities to petrology: examples from accreted arc roots.” All lab groups continued their specific preparations and worked on their methods sections.

Daily Science Report for 7 April 2014

LOCATION: In transit to Site U1436 (proposed site IBM-4GT)

SCIENCE UPDATE: The shipboard science party received two seminar talks entitled “Closest proximal analogue to the Expedition 350: the rear arc facies of the Izu Peninsula, Japan” and “Coring disturbances in IODP piston cores—examples from various DSDP, ODP and IODP expeditions.” All scientists were officially on their assigned shifts by noon. A “pre-spud” operational planning meeting was held with senior Siem and IODP personnel for both Sites U1436 (proposed site IBM-4GT) and U1437 (proposed site IBM-3C). All lab groups continued their specific preparations and worked on their methods sections. ETA at Site U1436 is noon on 8 April. Core is expected on deck late night of 8 April.

Daily Science Report for 6 April 2014

LOCATION: In transit to Site U1436 (proposed site IBM-4GT)

SCIENCE UPDATE: The shipboard science party held another sample request meeting, following the previous day’s discussions, to organize the remaining types of requests. The Operations Superintendent led another two ship tours for the second half of the science party, while the first half of the science party received hands-on training from the Curator in the use of the sample registration application. The core describers held a “walk through” of the core laboratory to discuss detailed workflow and tasks with the Staff Scientist and technician. All lab groups worked on their methods sections. ETA at Site U1436 is early morning on 8 April. Core is expected on deck in the evening of 8 April.

Daily Science Report for 5 April 2014

LOCATION: In transit to Site U1436 (proposed site IBM-4GT)

SCIENCE UPDATE: The shipboard science party held a meeting to discuss and organize sample requests. The Operations Superintendent led two ship tours, for half of the science party. The other half of the scientists received hands-on training in the use of the sample registration application. The Staff Scientist presented report writing procedures and the expected publication products for Expedition 350. Core describers met once more to refine data capture spreadsheets and nomenclature to be used.

Daily Science Report for 4 April 2014

LOCATION: In transit to Site U1436 (proposed site IBM-4GT)

SCIENCE UPDATE: The vessel departed from Keelung with the last line away at 0753 h. Scientific preparations continued, including paleomagnetics and core description laboratory group meetings. The Operations Superintendent and the Logging Staff Scientist gave presentations about the coring and logging systems deployed on the JOIDES Resolution in preparation for ship tours scheduled for the following two days. The Staff Scientist presented procedures and tools involved in registering samples, collecting data, and computing depths in preparation for hands-on training during the following two days. The sampling and shipboard measurement plan for Site U1436 (proposed site IBM-4GT) was established.

Daily Science Report for 3 April 2014

LOCATION: Keelung, Taiwan, Passenger Terminal, Berth E4

SCIENCE UPDATE: The science party continued their deliberations on how to describe volcanic sediments and rocks. A meeting was held with the chemistry laboratory group to discuss the shipboard analytical program and work tasks. In the afternoon, all scientists gave a brief presentation of their research proposal and sample request. Port call supply and maintenance activities were completed according to the port call work plan.

Daily Science Report for 2 April 2014

LOCATION: Keelung, Taiwan, Passenger Terminal, Berth E4

SCIENCE UPDATE: The science party received a presentation of planned activities from the IBM Rear Arc Expedition (350) education and outreach officers. The Assistant Laboratory Officer gave a life on board presentation. Shipboard core description preparations continued and we reached out to continue involvement of the IBM Expedition 351 and 352 participants who participated in the IBM pre-cruise core description workshop in January 2014. A meeting was held with the Expedition 350 biostratigraphers to define work tasks. Port call supply and maintenance activities continued according to the port call work plan.

Daily Science Report for 1 April 2014

LOCATION: Keelung, Taiwan, Passenger Terminal, Berth E4

SCIENCE UPDATE: The science party received an introduction to the IBM Reararc Expedition 350 project plan and shipboard work requirements from the Staff Scientist, followed by an introduction to the IBM science objectives from the Co-chief Scientists. The Staff Scientist, Operations Superintendent, and Logging Staff Scientist then gave an overview, and entertained discussions, of the operational strategy for the expedition. A kick-off meeting was held for the core description group. Port call supply and maintenance activities continued according to the port call work plan.