IODP Expedition 361
Southern African Climates (Agulhas Current Density Profile APL)
Daily Science Report for 31 March 2016
Location:
In transit
Cape Town, South Africa
Science Update: After the 103 nmi transit from Site U1479 to Cape Town, the pilot boarded the ship at 1230 h. The IODP Southern African Climates Expedition (361) ended with the first line ashore at 1336 h.
Daily Science Report for 30 March 2016
Location:
Hole U1479I (proposed site CAPE-01C, 35°03.5286′S, 17°24.0493′E, 2613.4 m water depth)
In transit to Cape Town, South Africa
Science Update: The vessel spent the remaining expedition operational time waiting on weather. At 0400 h on 30 March the drill pipe was recovered and the bit cleared the rig floor at 1215 h. The seafloor positioning beacon was recovered at 0754 h, the rig floor was secured for transit at 1335 h, the thrusters were raised at 1415 h, and the vessel was underway to Cape Town, South Africa, at 1436 h. The vessel is scheduled to be at the pilot station at 0700 h on 31 March.
The science laboratory teams completed their Site U1479 reports and methods sections.
Daily Science Report for 29 March 2016
Location: Site U1479 (proposed site CAPE-01C, 35°03.5289′S, 17°24.0624′E, 2618.3 m water depth)
Science Update: Coring today was impacted by poor sea conditions that deteriorated during the latter half of the day. The vessel was offset 20 m west of Hole U1479B and Hole U1479F was begun at 0125 h. Core U1479F-1H did not recover a mudline and instead had a full core barrel. Core U1479F was abandoned for a second mudline attempt. The bit was raised 3.0 m and Hole U1479G was begun at 0225 h. Core U1479G-1H recovered 9.29 m of sediment, including the mudline. The stratigraphic correlators requested another mudline and the bit was raised another 4.0 m and Hole U1479H was begun at 0325 h on 29 March. Core U1479H-1H to 5H penetrated to 43.6 m DSF followed by a 4.0 m interval that was advanced without recovery to offset coring gaps for stratigraphic correlation. Cores U1479H-7H to 10H (47.6–85.6 m DSF) experienced poor APC recovery (75%). While taking Cores U1479H-7H and 9H, the flap style core catcher failed to close and several meters of core were lost. Because of this, a critical stratigraphic interval was not cored, so we decided to terminate the hole. The drill string was pulled out of the hole with the bit clearing the seafloor at 1130 h. Hole U1479I was begun at 1200 h and Core U1479I-1H recovered a 6.3 m mudline core. The hole was then advanced without recovery to 41.0 m DSF. The flapper style core catcher failed to close yet again while taking Core U1479I-3H and only 2.35 m were recovered. Core U1479I-4H recovered a full core barrel, but Core U1479I-5H misfired when the shear pins on the core barrel sheared early due to rough sea conditions. The decision was made to stop coring operations until weather conditions improved. The drill string was pulled from the hole and the bit cleared the seafloor at 1820 h on 29 March, ending Hole U1479I. The day ended with the vessel waiting on weather.
All of the cores from Site U1479 have been processed. Cores U1479G-1H, U1479H-1H to 10H, and U1479I-1H to 5H contain light greenish gray nannofossil ooze with foraminifers. The science laboratory teams are finalizing their Site U1479 reports and Methods sections.
Daily Science Report for 28 March 2016
Location: Hole U1479E (proposed site CAPE-01C, 35°03.5402′S, 17°24.0623′E, 2615.1 m water depth)
Science Update: After waiting on weather for 12 h, Hole U1479E was begun at 0325 h. The weather conditions were not ideal for coring and the hole was drilled without recovery to 90.0 m DSF in order to retrieve better quality cores from deeper in the section. Cores U1479E-2H to 8H (90.0–156.5 m CSF-A) were recovered, followed by a 2.0 m drilled interval to offset coring gaps for stratigraphic correlation. APC coring resumed with Cores U1475E-10H to 12H (158.5–187.0 m CSF-A). The hole was advanced without recovery to 229.0 m DSF to core specific stratigraphic intervals required for completing the spliced section. The hole ended after the recovery of Cores U1479E-14H to 18H (229.0–276.5 m CSF-A). The drill string was pulled from the hole with the bit clearing the seafloor at 2335 h. A total of 15 APC cores were taken over a 142.5 m cored interval with 104% core recovery.
Cores U1479E-2H to 18H contain light greenish gray nannofossil ooze. These cores are strongly disturbed as a result of the poor weather conditions. The laboratory teams continue to process cores from Site U1479 and are working on their final expedition reports.
Daily Science Report for 27 March 2016
Location: Site U1479 (proposed site CAPE-01C, 35°03.53′S, 17°24.06′E, 2618.3 m water depth)
Science Update: After completing coring at Hole U1479C, the drill string was pulled out of the hole with the bit clearing the seafloor at 0250 h. The vessel was offset 20 m east of Hole U1479B and Hole U1479D was begun at 0450 h. Cores U1479D-1H to 12H penetrated from the seafloor to 103.4 m; a single 2.0 m interval was advanced without coring (25.4–27.4 m) to adjust coring gaps between holes. After retrieving Core U1479D-12H, the drill string was pulled from the hole due to deteriorating sea conditions. The bit cleared the seafloor at 1510 h and the vessel spent the rest of the day waiting for the weather to improve.
Cores U1479C-16H to 32H (134.0–296.03 m CSF-A) and U1479D-1H (0–9.39 m CSF-A) contain light greenish gray nannofossil ooze. The Micropaleontology and Geochemistry Laboratories have completed their analyses for Site U1479 and are finalizing their site reports. The laboratory teams continue to process cores and are preparing for the end of the expedition.
Daily Science Report for 26 March 2016
Location: Hole U1479C (proposed site CAPE-01C, 35°03.5289′S, 17°24.0624′E, 2618.3 m water depth)
Science Update: APC coring continued in Hole U1479C with the recovery of Cores U1479C-13H to 32H (105.5–295.5 m CSF-A). The total core recovery at Hole U1479C was 103%.
Cores U1479B-29H to 32H (262.70–301.03 m CSF-A) and U1479C-2H to 15H (1.0–134.47 m CSF-A) contain light greenish gray nannofossil ooze. The abundance of foraminifers varies throughout the section. The described cores are moderately to strongly bioturbated. The biostratigraphy and paleomagnetic stratigraphy of the site continue to be refined.
Daily Science Report for 25 March 2016
Location: Hole U1479C (proposed site CAPE-01C, 35°03.5289′S, 17°24.0624′E, 2618.3 m water depth)
Science Update: APC coring continued in Hole U1479B with the recovery of Cores U1479B-21H to 32H to 300.7 m CSF-A. The total core recovery at Hole U1479B is 99%. After completing coring operations at Hole U1479B, the drill string was pulled out of the hole and the bit cleared the seafloor at 1920 h. The vessel was offset 10 m north of Hole U1479B and Hole U1479C was begun with a 1.0 m washed interval. Cores U1479C-2H to 12H (1.0–105.5 m CSF-A) were retrieved.
Cores U1479B-13H to 28H (110.7–263.22 m CSF-A) contain light greenish gray nannofossil ooze. The abundance of foraminifers varies throughout the section. The described cores are moderately to strongly bioturbated. The average carbonate content of the sediments is ~62 wt%. Paleomagnetic results suggest that the Gauss/Matuyama boundary (2.581 Ma) is found in Core U1479B-14H and the Gilbert/Gauss boundary (3.596 Ma) is found in Core U1479B-18H. Calcareous nannofossil biostratigraphy indicates that the base of Hole U1479B is ~7.4 Ma in age.
Daily Science Report for 24 March 2016
Location: Hole U1479B (proposed site CAPE-01C, 35°03.5289′S, 17°24.0621′E, 2618.3 m water depth)
Science Update: The vessel arrived at Site U1479 and the thrusters were lowered at 0354 h. The APC/XCB bottom-hole assembly (BHA) and drill string were made up and deployed to 2610 mbsl. Hole U1479A began at 1150 h and recovered 1.0 m of sediment. The science team decided that a longer, more pristine mudline core was desired and Hole U1479A was abandoned. Hole U1479B began at 1255 h and Cores U1479B-1H to 20H (0–186.7 m CSF-A) were recovered.
Cores U1479A-1H and U1479B-1H to 12H (0–111.06 m CSF-A) contain light gray to light greenish gray nannofossil ooze with foraminifers and quartz. Moderate to strong bioturbation is observed throughout the cores. Calcareous microfossils are well preserved and biostratigraphy indicates that Sample U1479B-20H-CC is ~4 Ma.
Daily Science Report for 23 March 2016
Location: In transit to proposed Site CAPE-01C (U1479)
Science Update: The science laboratory teams continue to work on reports for Sites U1477 and U1478 and presented their results from the two sites. The vessel is estimated to arrive at Site U1479 at 0300 h on 24 March.
Daily Science Report for 22 March 2016
Location: In transit to proposed site CAPE-01C (U1479)
Science Update: The science laboratories finished processing the remaining cores from Hole U1476E. Cores U1476E-23H to 25H (206.3–235.39 m CSF-A) contain greenish gray nannofossil ooze with foraminifers, quartz, and clay. Moderate bioturbation and diagenetic alterations are observed throughout the cores. The science laboratory teams continue to work on reports for Sites U1477 and U1478. The vessel is estimated to arrive at Site U1479 at 1200 h on 24 March.
Daily Science Report for 21 March 2016
Location: In transit to proposed Site CAPE-01C (U1479)
Science Update: The final cores of Hole U1478D and Cores U1476E-13H to 22H were described. Cores U1478D-10H to 24F (75.2–216.35 m CSF-A) contain dark greenish gray sand with foraminifers alternating with dark greenish gray clayey silt with nannofossils or foraminifers. The sand is primarily composed of quartz. Shell fragments of bivalves and gastropods are observed. The average total organic carbon (TOC) content of Hole U1478A is 0.5% and ranges from 0% to 1.25%. Cores U1476E-13H to 22H (111.3–206.83 m CSF-A) are composed of greenish gray nannofossil ooze with foraminifers, quartz, and clay. Moderate bioturbation and diagenetic alterations are observed throughout the cores. The science laboratory teams continue to revise and compose reports for Sites U1477 and U1478. The vessel is estimated to arrive at Site U1479 at 1200 h on 24 March.
Daily Science Report for 20 March 2016
Location: In transit to proposed site CAPE-01C (U1479)
Science Update: Cores U1478C-18H to 38F (145.5–248.55 m CSF-A) and U1478D-1H to 9H (0–75.27 m CSF-A) contain dark greenish gray sand with foraminifers alternating with dark greenish gray clayey silt with nannofossils or foraminifers. The sand is primarily composed of quartz but also contains dolomite, hornblende, biotite, zircon, and glauconite. Shell fragments of bivalves and gastropods are observed. The laboratory teams continue to process cores from Hole U1478D and are working on Site U1477 and U1478 reports. The vessel is estimated to arrive at site CAPE-01C (U1479) at 0600 h on 24 March.
Daily Science Report for 19 March 2016
Location: In transit to proposed Site CAPE-01C (U1479)
Science Update: After completing coring operations at Hole U1478C, the drill string was pulled from the hole with the bit clearing the seafloor at 0219 h. The vessel was offset 20 m south of Hole U1478A and Hole U1478D began at 0310 h. Core U1478D-1H recovered 6.7 m of sediment and the seafloor was estimated at 490.7 mbsl. Hole U1478D was drilled without recovery from 6.7 to 8.7 mbsf to offset coring gaps for stratigraphic correlation. The APC system was deployed for Cores U1478D-3H to 17H (8.7–151.2 mbsf). A center bit was installed and the hole was drilled without coring from 151.2 to 190.5 mbsf since this section was completely recovered in the previous holes and we wanted to target gaps deeper in the section. The half-length APC (HLAPC) was deployed for Cores U1478D-19F and 20F (190.5–199.9 msbf). The drill string was then advanced without recovery 2.0 m and Cores U1478D-22F to 24F (201.9–211.3 mbsf) were retrieved. The total core recovery for Hole U1478D is 102%. After completing coring operations at Hole U1478D, the drill string was pulled from the hole. The bit cleared the seafloor at 1350 h and the rig floor at 1540 h. The rig floor was secured for transit and the vessel began the transit to proposed site CAPE-01C at 1630 h. The vessel is estimated to arrive at site CAPE-01C (U1479) at 0600 h on 24 March.
Cores U1478B-18H to 34F (153.0–247.3 m CSF) and U1478C-1H to 17H (0–145.64 m CSF) contain dark greenish gray sand with foraminifers alternating with dark greenish gray clayey silt with nannofossils or foraminifers. Shell fragments of bivalves and gastropods, as well as a coral, are observed. Biostratigraphy and paleomagnetics suggest that sedimentation rates at Site U1478 were ~4 cm/k.y. from ~4 to 1.6 Ma and increased to ~9 cm/k.y. from 1.6 Ma to Recent. Carbonate content ranges from 16 to 54 wt% with an average of 29 wt%.
Daily Science Report for 18 March 2016
Location: Hole U1478C (proposed site LIM-01B, 25°49.2604′S, 34°46.1705′E, 489.9 m water depth)
Science Update: The day began with continued coring operations at Hole U1478B. The half-length APC (HLAPC) was used for Cores U1478B-20F to 21F (172.0–181.4 mbsf). We switched back to the APC for Core U1478B-22H, which recorded a partial stroke so the HLAPC was used for the remainder of Hole U1478B (Cores 23F–34F). After reaching 247.3 mbsf, the drill string was pulled from the hole and operations at Hole U1478B ended with the bit clearing the seafloor at 1015 h. The vessel was moved 20 m east of Hole U1478A and Hole U1478C began at 1110 h. After retrieving a 1.5 m mudline in Core U1478C-1H, the hole was washed down without recovery to 3.0 mbsf to offset coring gaps for stratigraphic correlation. Cores U1478C-3H to 21H penetrated from 3.0 to 178.5 mbsf. The interval from 164.5 to 169.0 mbsf was drilled without recovery to adjust coring gaps between holes. The HLACP was deployed for Cores U1478C-21F to 38F (178.5–248.3 mbsf); three intervals totaling 4 m were advanced without coring in this interval.
Cores U1478A-19H to 32F and U1478B-2H to 17H were described. These cores contain dark greenish gray sand with foraminifers alternating with dark greenish gray clayey silt with nannofossils or foraminifers. Bivalve and gastropod shell fragments, as well as unidentified shell fragments, are common in the cores. A complete stratigraphic section has been recovered to 185 m CSF-A. The Hole U1478A biostratigraphy continues to be refined. All of the 127 interstitial water whole rounds from Holes U1478A and U1478B have been squeezed.
Daily Science Report for 17 March 2016
Location: Hole U1478B (proposed site LIM-01B, 25°49.2492′S, 34°46.1590′E, 487.9 m water depth)
Science Update: Hole U1478A was begun at 0320 h. Water depth was calculated at 487.9 m based on the 6.7 m of sediment recovered in Core U1478A-1H. The APC system was used on Cores U1478A-1H to 21H (0 to 196.7 mbsf). The half-length APC (HLAPC) was deployed after significant overpull (70,000 lbs) was recorded while removing Core U1478A-21H. Cores U1478A-22F to 32F (196.7–248.4 mbsf) were retrieved. A total of 252.25 m of sediment was recovered over a 248.4 m cored interval in Hole U1478A (102% recovery). The drill pipe was pulled from the hole and the bit cleared the seafloor at 1805 h. The vessel was offset 20 m north of Hole U1478A and Hole U1478B was begun at 1840 h. Hole U1478B was drilled without recovery from 0 to 1.0 m to offset coring gaps between Holes U1478A and U1478B. The APC system was used on Cores U1478B-2H to 19H (1.0 to 172.0 mbsf).
Cores U1478A-1H to 18H (0–168.45 mbsf) contain dark greenish gray sand with foraminifers alternating with dark greenish gray clayey silt with nannofossils or foraminifers. Shells and shell fragments are common in the cores. Minima in magnetic susceptibility correspond to intervals with abundant biogenic components and dolomite rhombs. Foraminifers and calcareous nannofossils are abundant and well preserved. Biostratigraphy indicates that the base of Hole U1478A is ~3.85 Ma. The cores have a good paleomagnetic signal and the Brunhes/Matuyama boundary (0.781 Ma) is observed in Section U1478A-9H-2A.
Daily Science Report for 16 March 2016
Location: In transit to proposed Site LIM-01B (U1478)
Science Update: The vessel completed the 422 nmi transit to Site U1478. The thrusters were lowered at 2215 h and a positioning beacon was deployed at 2315 h.
Cores from the previous site continue to be described. Cores U1477C-8H to 17F (58.0–119.35 m CSF-A) contain very dark gray silty clay. Shell fragments are present throughout the cores and gas expansion cracks are pervasive. The science laboratory teams continue to work on reports for Sites U1476 and U1477.
Daily Science Report for 15 March 2016
Location: In transit to proposed Site LIM-01B (U1478)
Science Update: After reaching 119.4 mbsf in Hole U1477C, the drill string was pulled out of the hole with the bit clearing the seafloor at 0415 h and the rig floor at 0555 h. The vessel began the transit to proposed site LIM-01B at 0642 h. The vessel is estimated to arrive at LIM-01B at 0100 h on 17 March.
Cores U1477B-10H to 26F and U1477C-2H to 7H contain very dark gray silty clay. Shell fragments are present throughout the cores and gas expansion cracks are pervasive. The average carbonate content for Hole U1477A is 5 wt% and the average total organic carbon content is 0.6 wt%. The science laboratory teams continue to process cores from Hole U1477C and are working on Site U1476 and U1477 reports.
Daily Science Report for 14 March 2016
Location: Hole U1477C (proposed site ZAM-05A, 19°21.2928′S, 36°54.9066′E, 429.2 m water depth)
Science Update: After reaching 181.2 mbsf in Hole U1477A, the drill string was removed from the hole with the bit clearing the seafloor at 0615 h. The vessel was moved 20 m north of Hole U1447A and Hole U1477B began at 0705 h. The APC system was deployed for Cores U1477B-1H to 12H (0–108.6 mbsf). After two partial strokes with the APC, the half-length APC (HLAPC) was used for Cores U1447B-13F to 26F (108.6–174.4 mbsf). A total of 185.73 m of core was recovered over a 174.4 m cored interval in Hole U1477B (106%). The drill string was pulled from the hole and the bit cleared the seafloor at 1910 h. The vessel was offset 20 m south of Hole U1477A and Hole U1477C began at 1950 h with a 1.0 m drilled interval. The APC system was used for Cores U1477C-2H to 10H (1.0–86.5 mbsf). After two partial stokes on Cores U1477C-9H and 10H, the HLAPC was deployed for Cores U1477C-11F to 17F (86.5–119.4 mbsf). A total of 121.7 m of core was recovered from a 118.4 m cored interval (103%).
Cores U1477A-12H to 27X and U1477B-1H to 9H contain very dark gray silty clay. Shell fragments are present throughout the cores. Many of the cores are fractured from core expansion. All of the interstitial water samples are squeezed and the sulfate–methane transition zone is found at ~16 mbsf in Hole U1477A. Cores from Holes U1447B continue to be processed in the laboratories.
Daily Science Report for 13 March 2016
Location: Hole U1477A (proposed site ZAM-05A, 19°21.2930′S, 36°54.8962′E, 429.2 m water depth)
Science Update: The vessel arrived at Site U1477 at 0942 h and the thrusters were lowered at 1015 h. The APC/XCB bottom-hole assembly and drill string were deployed to 412.2 mbsl for the first core. The first two coring attempts resulted in water cores, and after lowering the bit a total of 15 m, Hole U1477A began at 1535 h. Core U1477A-1H recovered 7.52 m of sediment and the water depth was calculated at 429.2 m. Cores U1477A-1H to 11H penetrated from the seafloor to 102.5 m DSF. After two partial strokes with the APC, the half-length APC (HLAPC) was used for Cores U1477A-12F to 26F (102.5–173.0 m DSF). The XCB was used for Core U1477A-27X (173.0–181.2 m DSF). The total core recovery for Hole U1477A is 182.53 m from the 181.2 m cored interval (101%).
Cores U1476E-10H to 12H (82.8–111.91 m CSF-A) contain greenish gray nannofossil ooze with foraminifers and quartz. Moderate bioturbation and pyrite are observed in these cores. After describing these two cores, the remaining cores from Hole U1476E were stored for processing later in the cruise. This was done to prepare the laboratories for the rapid core recovery at Site U1477. Cores U1477A-1H to 11H (0–101.89 m CSF-A) were described. Very dark gray clayey sand with foraminifers is found in the uppermost 3.0 m of Hole U1477A. Below this, the cores contain very dark gray silty clay with shell fragments. The paleomagnetics indicate that the cores have normal polarity and are within the Brunhes chron. Calcareous microfossils are barren to few in Hole U1477A and are well preserved. One biostratigraphic event, the top of Globigerinoides ruber pink (120 k.y.), was found in Sample U1477A-16F-CC. Initial results suggest that sedimentation rates at Site U1477 are ~1 m/k.y.
Daily Science Report for 12 March 2016
Location: In transit to proposed Site ZAM-05A (U1477)
Science Update: The day began tripping drill pipe. The positioning beacon was recovered at 0102 h. The rig floor was secured for transit at 0335 h, the thrusters were raised, and the vessel began the transit to Site ZAM-05A at 0349 h. The vessel is estimated to arrive on site at 1000 h on 13 March.
Cores U1476D-20H to 25H (172.0–229.42 mbsf) contain greenish gray nannofossil ooze with foraminifers and quartz. Cores U1475E-1H to 9H (0–82.53 mbsf) contain alternating layers of greenish gray nannofossil-bearing foraminifer ooze with quartz and clay and greenish gray foraminifer-rich nannofossil ooze. Slight to strong bioturbation is observed in these cores and pyrite nodules are present. The laboratory teams continue to process cores from Site U1476 and work on site reports.
Daily Science Report for 11 March 2016
Location: Hole U1476E (proposed site MZC-01C, 15°49.2638′S, 41°46.1240′E, 2165.2 m water depth)
Science Update: Cores U1476E-15H to 25H (130.3–234.8 mbsf) were retrieved with 105% core recovery. After reaching 234.8 mbsf the drill string was pulled from the hole and the bit cleared the seafloor at 2050 h. The day ended with the vessel being prepared for transit to Site ZAM-05A.
Cores U1475D-5H to 19H (29.50–172.20 mbsf) contain greenish gray nannofossil ooze with foraminifers and quartz. Moderate to strong bioturbation and pyrite are observed. Sedimentation rates at the site are ~3.0 cm/k.y. based on biostratigraphy. Carbonate content ranges from 45–75 wt% and broadly follows magnetic susceptibility trends.
Daily Science Report for 10 March 2016
Location: Hole U1476E (proposed site MZC-01C, 15°49.2638′S, 41°46.1240′E, 2165.2 m water depth)
Science Update: Cores U1476D-11H to 25H (86.5–229.0 mbsf) were retrieved with 105% core recovery. After reaching 229.0 mbsf the drill string was pulled from the hole and the bit cleared the seafloor at 2015 h. The vessel was offset 20 m south of Hole U1476A and Hole U1476E began at 2125 h. Cores U1476E-1H to 14H (0–130.3 mbsf) were retrieved with 103% core recovery.
Cores U1476B-4H to 16H (24.9–148.4 mbsf), U1476C-1H (0–5.7 mbsf), and U1476D-2H to 4H (1.0–29.5 mbsf) were described. In the upper ~33 m the core lithology alternates between greenish gray nannofossil-rich foraminifer ooze and greenish gray foraminifera-rich nannofossil ooze. Slight to moderate bioturbation and pyrite are observed. Below ~33 m, the cores contain greenish gray nannofossil ooze with foraminifera and quartz. Moderate bioturbation and pyrite are observed in these cores. The cores from Holes U1476A and U1476B have a strong drilling magnetic overprint that is problematic for paleomagnetics. The biostratigraphy continues to be refined and a complete stratigraphic section was recovered to 229.0 mbsf. Pore water nitrate decreases from 45 µM at the top of Hole U1476B to 0 µM at ~1.5 mbsf.
Daily Science Report for 9 March 2016
Location: Hole U1476D (proposed site MZC-01C, 15°49.2530′S, 41°46.1352′E, 2165.5 m water depth)
Science Update: After reaching APC refusal in Hole U1476A at 224.2 mbsf, the drill string was pulled out of the hole with the bit clearing the seafloor at 0705 h. The vessel was offset 20 m north and Hole U1476B began at 0815 h. Cores U1476B-1H to 16H (0–148.4 mbsf) were recovered and sampled for high-resolution pore water chemistry. The drill string was pulled from the hole and Hole U1476B ended at 2115 h with the bit clearing the seafloor. The core line was reheaded and the vessel was offset 20 m east of Hole U1476A. Hole U1476C began at 2225 h and Core U1476C-1H recovered 5.72 m of sediment. The stratigraphic correlation specialists determined that the coring gaps were aligned and Hole U1476C ended at 2245 h. Hole U1476D began at 2330 h with a 1.0 m interval that was drilled without coring. Cores U1476D-2H to 10H (1.0–86.5 mbsf) were retrieved with 103% core recovery.
Cores U1476A-14H to 24H (119.7–224.57 mbsf) and U1476B-1H to 3H (0–25.26 mbsf) have been described. Cores U1476A-14H to 24H contain greenish gray nannofossil ooze with foraminifera and quartz. The cores are moderately bioturbated and contain pyrite. Occasional infilled burrows contain sand sized grains of epidote. Cores U1476B-1H to 3H contain light greenish gray foraminifera ooze with nannofossils alternating with greenish gray foraminifera-rich nannofossil ooze with fine sands. These cores are slightly bioturbated and contain thin (<1 cm) layers of glauconite and pyrite. A total of 101 interstitial water whole-round samples were taken from Hole U1476B for shipboard and postcruise analysis. Sections U1476B-1H-1 through 2H-5 were sampled for pore water nitrate using rhizons. Thus far, a complete stratigraphic sequence at Site U1476 has been recovered to 86.5 mbsf.
Daily Science Report for 8 March 2016
Location: Hole U1476A (proposed site MZC-01C, 15°49.2535′S, 41°46.1242′E, 2165.7 m water depth)
Science Update: The vessel arrived at Site U1476 at 0048 h. The thrusters were lowered and the positioning beacon deployed at 0216 h. The APC/XCB bottom-hole assembly and drill string was made up and the bit lowered to 2155 mbsl for the first coring attempt. The first APC core was filled with water, so the bit was lowered 7 m for a second attempt. Hole U1476A began at 0935 h and Core U1476A-1H recovered 5.72 m. Cores 1H to 24H penetrated to 224.57 mbsf with 104% core recovery. Partial strokes were recorded for Cores U1476A-23H and 24H and Hole U1476A was terminated after reaching APC refusal depth.
Cores U1476A-1H to 13H (0–120.20 mbsf) contain light greenish gray foraminifer-bearing nannofossil ooze with silt and nannofossil ooze with foraminifers. Moderate bioturbation and pyrite is observed. The magnetic susceptibility record for Hole U1476A shows cyclic variations that strongly resemble global benthic oxygen isotope records. A continuous sequence of planktonic foraminifer and calcareous nannofossil datums are observed in Hole U1476A. Calcareous microfossils are well preserved and have a high abundance throughout the cored interval. Biostratigraphy indicates that the base of Hole U1476A is ~7 Ma in age.
Daily Science Report for 7 March 2016
Location: In transit to proposed Site MZC-01C (U1476)
Science Update: The vessel is underway to Site U1476 and is scheduled to arrive at 0100 h on 8 March. The pre-site meeting was held and the scientists were given a presentation on the Pleistocene biogeography of planktonic foraminifera. The science laboratory teams revised and submitted their final Site U1475 reports. We received communication from the U.S. Embassy that the vessel is cleared to begin scientific drilling operations in the Mozambique Channel.
Daily Science Report for 6 March 2016
Location: In transit to proposed Site MZC-01C (U1476)
Science Update: The vessel is underway to Site U1476 and is scheduled to arrive at 0100 h on 8 March. The scientists were given a presentation on organic biomarkers from African lakes. The science laboratory teams submitted drafts of their Site U1475 reports and site summaries.
Daily Science Report for 5 March 2016
Location: In transit to proposed Site MZC-01C (U1476)
Science Update: The vessel is underway to Site U1476 and is scheduled to arrive at 0600 h on 8 March. The scientists were given a presentation on Agulhas Leakage fauna. The science laboratory teams submitted drafts of their Site U1475 reports and site summaries.
Daily Science Report for 4 March 2016
Location: In transit to proposed Site MZC-01C (U1476)
Science Update: The vessel is underway to proposed Site MZC-01C (U1476) and is scheduled to arrive at 1200 h on 8 March. The scientists were given a presentation on sediment transport from the Zambezi River. The science laboratory teams continue to work on their Site U1475 reports.
Daily Science Report for 3 March 2016
Location: In transit to proposed Site MZC-01C
Science Update: We began the day assembling additional stands of drill pipe necessary for drilling operations in deeper waters at proposed site CAPE-01C. This was completed at 0930 h and the vessel began the transit to site CAPE-01C. At ~1330 h, we received news from the U.S. Embassy in Mozambique that the clearance agreement for operations in their waters was signed. We changed heading and began the transit to proposed Site MZC-01C. We are still awaiting the arrival of the official diplomatic note before we can start operations in Mozambique waters.
The science laboratory teams presented their results from Site U1475 and continue to work on their site reports.
Daily Science Report for 2 March 2016
Location: On station making up stands of drill pipe (33°56.00′S, 33°39.20′E)
Science Update: The vessel was underway to proposed Site ZAM-05A located in Mozambique waters. The U.S. Embassy in Mozambique provided a hard deadline to the Ministry of Fisheries of 2 March for acquiring clearance permission. At the end of the business day, permission to drill within the Mozambique exclusive economic zone was still pending. The decision was made to end the transit to ZAM-05A and take advantage of the good weather conditions to assemble 51 stands of drill pipe that will be used for drilling operations at alternate Site SubSAT-01D (redrill of ODP Site 1089). At 1730 h the vessel reduced speed and the thrusters were lowered at 1745 h. The day ended with drill pipe being assembled and racked. After these operations are complete, the vessel will begin the transit to proposed Site CAPE-01C.
All of the cores and samples from Site U1475 have been processed. The science laboratory teams are writing their site reports and preparing for the site results meeting.
Daily Science Report for 1 March 2016
Location: In transit to Site U1476 (proposed Site ZAM-05A)
Science Update: We continue to process Site U1475 cores while in transit to the next site. The vessel is estimated to arrive at Site U1476 (ZAM-05A) on 6 March. Cores U1475D-4H to 16H (24.5–143.0 mbsf) contain white gray to light greenish gray nannofossil-rich foraminifer ooze and nannofossil ooze with foraminifers, quartz, and diatoms. Moderate to strong bioturbation and pyrite is observed throughout the cores. Stratigraphic correlation is ongoing. The alkalinity of the pore water increases with depth from 4 to 16 mM. Pore water sulfate and pH decrease down hole and Fe is below the detection limit.