Daily Report for IODP Expedition 311, October 16, 2005
LOCATION: Site U1328 (CAS-06A)
SCIENCE UPDATE: After completing Hole 1328D to a total depth of 15.0 mbsf, the drill pipe was pulled back to the surface and the ship was offset 50 m to prepare for the coring of a special tools hole. Hole U1328E was spudded with the XCB at 00:40 hr. The primary focus of Hole U1328E was pressure coring, with XCB spot cores to recover gas hydrate from the top 40 mbsf, which contains the highest gas hydrate concentrations at this site, as interpreted from LWD data and previous scientific coring. The XCB coring in Hole U1328E did yield a number of high-quality samples of gas hydrate-bearing sediment as well as isolated gas hydrate pieces that were preserved in liquid nitrogen. XCB coring advanced the hole to 8.5 mbsf, where the FPC was deployed (Core U1328E-3E), which did not return under pressure. An XCB core was taken, followed by a PCS run at 15.1 mbsf (Core U1328E-5P), which did not return pressurized. Another XCB core was taken and then the HRC was deployed (Core U1328E-7Y), which also failed to return a core under pressure. Two XCB cores advanced the hole to 46.0 mbsf, followed by the center bit to drill the hole to 92.0 mbsf. The PCS Core U1328E-10P was deployed, returning under pressure, followed by a DVTP temperature measurement. The center bit was redeployed and the hole was drilled to 197.0 mbsf and FPC pressure core system was deployed, but it improperly retracted into the autoclave and failed to yield a pressurized core. An additional DVTP survey was conducted after the last FPC core run at 199 mbsf.