The thermal conductivity of gas hydrate-bearing sediments is a key parameter used to evaluate the heat transfer process relevant to phase transformation during gas hydrate production and to assess heat flux properties within the hydrate stability zone. Relatively few thermal conductivity values for in-situ hydrate-bearing sediments and laboratory hydrate-bearing sediments have been reported for under saturated conditions with vertical effective stress. In this study, we used sandy sediments obtained during the Ulleung Basin Gas Hydrate Expedition 2 (UBGH2) Expedition in Korea to synthesize methane hydrate-bearing sediments with saline pore fluid. The transient plane source method was implemented to measure the thermal conductivity of specimens with variable gas hydrate saturations. The measured thermal conductivity was ~1.47W/m/K and was independent of hydrate saturation. Results from additional tests of ice- and water-unsaturated sediments were also compared to our findings. Both geometric mean and 3D thermal network models corroborated the experimentally measured thermal conductivities assuming expected physical properties.
Bibliographical noteFunding Information:
The authors wish to thank those that contributed to the success of the Second Gas Hydrate Drilling Expedition in the Ulleung Basin (UBGH2). Notably we wish to thank the co-chief scientists, the captains, crew and shipboard scientific party of the D/V Fugro Synergy. We also wish to acknowledge the support of the Gas Hydrate Research and Development Organization (GHDO) of the Ministry of Trade, Industry and Energy , Republic of Korea. Special appreciation is extended to Korea Institute of Geoscience and Mineral Resources (KIGAM, No. 2012-1143 ), Korea National Oil Corporation, Korea Gas Corporation, Korea Ocean Research and Development Institute , Han Yang University , Korea Advanced Institute of Science and Technology , U.S. Geological Survey , Oregon State University , GeoTek , Schlumberger, and Fugro Well Services who supported and participated in the 2010 UBGH2 drilling campaign.
All Science Journal Classification (ASJC) codes
- Economic Geology