georefid:2004-003402SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=10.1130/G19863.1<gco:CharacterString>Critical pressure and multiphase flow in Blake Ridge gas hydrates</gco:CharacterString>2003-01-01publicationgeorefid:2004-003402doi:10.1130/G19863.1Flemings, Peter B.Pennsylvania State University, Department of Geosciences, University Park, PA, United StatesauthorLiu, XiaoliU. S. Geological Survey, United StatesauthorWinters, William J.authorGeological Society of America (GSA), Boulder, CO, United StatespublisherdocumentHardcopyGeology (Boulder)31 (12)1057-1060We use core porosity, consolidation experiments, pressure core sampler data, and capillary pressure measurements to predict water pressures that are 70% of the lithostatic stress, and gas pressures that equal the lithostatic stress beneath the methane hydrate layer at Ocean Drilling Program Site 997, Blake Ridge, offshore North Carolina. A 29-m-thick interconnected free-gas column is trapped beneath the low-permeability hydrate layer. We propose that lithostatic gas pressure is dilating fractures and gas is migrating through the methane hydrate layer. Overpressured gas and water within methane hydrate reservoirs limit the amount of free gas trapped and may rapidly export methane to the seafloor.completedEconomic geology, geology of energy sourcesOceanographyaliphatic hydrocarbonsalkanesAtlantic OceanBlake-Bahama Outer Ridgecontinental slopecoresfracturesgas hydratesgas seepshydrocarbonsLeg 164marine sedimentsmethanemigrationnatural gasNorth AtlanticNorth CarolinaOcean Drilling Programocean floorsODP Site 997organic compoundsoverpressurepermeabilitypetroleumporositypressureresourcessedimentsstabilityUnited Statesurn:org.iodp:exp:164urnlargerWorkCitationcampaignurn:org.iodp:exp:164:site:997urnlargerWorkCitationstudyurn:org.iodp:exp:164urnlargerWorkCitationcampaignEnglishgeoscientificInformation-75.2807-75.280731.503531.5035