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doi:10.2204/iodp.proc.347.105.2015 OperationsTransit to Hole M0061AThe Greatship Manisha left Site M0060 at 1030 h on 1 October 2013, on route to Site M0061 (proposed Site BSB-10) via Øresund. At 1400 h, the vessel slowed while a small crew vessel came alongside to deliver drill supplies and offload microbiology “live” samples. A pilot boarded the Greatship Manisha at 0755 h on 4 October, guiding the vessel through the Ångermanälven River estuary, arriving at Hole M0061A by 1000 h. Hole M0061AOperations commenced as soon as the vessel had established position and built the dynamic positioning (DP) model (Table T1). Ten piston cores were recovered to deck before the evening of 4 October 2013. Initially, seawater was used for pumping, but because of the presence of sand, Guar gum drill mud was used deeper than 20.0 meters below seafloor (mbsf). At 2220 h, a hammer sample was collected, which retrieved a sample of granite. The hole was terminated at 25.20 mbsf at 2300 h on 4 October. A total of 11 coring attempts were made in Hole M0061A to a maximum depth of 25.20 mbsf. Hole recovery was 94.87%. Hole M0061BThe vessel moved to establish position for Hole M0061B under DP. At 2340 h, operations commenced with the first core recovered to deck at 0000 h on 5 October 2013. At 0506 h, the tool became stuck. Following release of the overshot and flushing, the tool was freed and coring continued. Nine piston cores were recovered during the morning of 5 October, reaching a maximum depth of 28.70 mbsf. As with Hole M0061A, the recovery of sand and silt led to the termination of the hole, and the vessel prepared to move to Hole M0061C at 0645 h on 5 October. A total of nine coring attempts were made in Hole M0061B, reaching a maximum depth of 28.70 mbsf. Hole recovery was 97.98%. Hole M0061CPiston coring operations in Hole M0061C commenced at 0725 h on 5 October 2013, after the vessel had bumped across under DP. This hole was cored to produce a composite record with the previous holes and ensure an appropriate volume of material was collected to meet future sampling requirements. Consistent with Holes M0061A and M0061B, the hole was terminated upon encountering the sand lithology beneath the varved sequence. A total of seven piston coring attempts were made in Hole M0061C, reaching a depth of 23.1 mbsf. Hole recovery was 98.4%. Holes M0061K, M0061L, and M0061MThree Rumohr cores were also collected at this site on 5 October 2013. The corer was deployed over the starboard side of the vessel using a system of winches. In total, 0.97 m (Hole M0061K), 0.96 m (Hole M0061L), and 0.92 m (Hole M0061M) of sediment was recovered in the attempt to capture the sediment/water interface without disturbance from the landing of the seabed template. |