Portal de Periódicos da CAPES

Site M0078

2019; Linguagem: Inglês

10.14379/iodp.proc.381.104.2019

2377-3189

L.C. McNeill, D. J. Shillington, Gareth Carter, Jez Everest, E. Le Ber, Richard Collier, Aleksandra Cvetkoska, Gino de Gelder, Paula Diz, Mai‐Linh Doan, Mary Ford, Robert L. Gawthorpe, Maria Geraga, Jack Gillespie, Romain Hemelsdaël, E. Herrero‐Bervera, M. Ismaiel, Liliane Janikian, Katerina Kouli, S. Li, M.L. Machlus, Marco Maffione, Carol Mahoney, Georgios Michas, C. Miller, Casey W. Nixon, Sabire Asli Oflaz, Abah P. Omale, Konstantinos Panagiotopoulos, Sofia Pechlivanidou, M.P. Phillips, Simone Sauer, Joana Seguin, Spyros Sergiou, Natalia Zakharova,

Hydrocarbon exploration and reservoir analysis

During International Ocean Discovery Program (IODP) Expedition 381, cores were recovered from two holes at Site M0078 (Fig- ures F1,F2).In total, 20.27 days were spent on station, with an average core recovery of 88% for the site (Table T1).Hole M0078A was drilled to 610.43 meters below seafloor (mbsf ), and Hole M0078B was drilled to 55.85 mbsf.In Hole M0078A, the Fugro Wison Extended Piston (WEP) system was used to core the upper 75 m, and the Fugro Corer in push mode was used for the next 124 m, followed by the same corer in percussive mode for 25 m.The Fugro Extended Marine Core Barrel (FXMCB) (rotary) was used to core the final 386 m of the borehole.In Hole M0078B, the Fugro Corer in push mode was used throughout to the base of the hole at 55.85 mbsf. Transit to Hole M0078AThe D/V Fugro Synergy prepared to sail on the evening of 22 October 2017, and the vessel departed the Port of Corinth at 1955 h (local time) for the first coring site.At 2130 h, the Fugro Synergy arrived at Site M0078, and a dynamic positioning model was established.A reference beacon was deployed, and a sound velocity profile was conducted.Water depths for Holes M0078A and M0078B are 859.5 and 864 m, respectively. Coring operations Hole M0078AAt 0145 h (local time) on 23 October 2017, the seabed frame (SBF) was deployed, and the drilling crew began running pipe.However, running pipe took longer than anticipated because rust at the joints resulted in the need for a thorough cleaning prior to deployment.During the evening of 23 October, the first cores were recovered with the first core on deck at 2135 h.The SEADEVIL (an addition to the standard seabed template) was used to accurately spud in and collect a seabed/water interface sample.The WEP system was lowered to approximately 10 cm above the seabed and energized.The first core was 2.65 m long.The next attempt at coring was unsuccessful, and the decision was made to wash through this interval.Following the wash through, coring continued throughout 23 and 24 October, generally with high recovery rates.On 25 October, recovery gradually worsened, prompting a switch to the Fugro Corer in push mode with flapper and finger catchers to optimize recovery.Initially, 3 m runs were conducted, but runs were extended to 4.7 m on the evening of 25 October.At 2130 h on 25 October, a communication issue arose with the SEADEVIL, leading to its recovery on deck at 0300 h on 26 October for assessment.Further investigation identified a printed circuit