The gas hydrate potential in the South China Sea

• Published in: Journal of petroleum science & engineering Vol. 88-89; pp. 41 - 47
• Main Author: Trung, Nguyen Nhu
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2012
• Subjects: China; Gas hydrate; Gas hydrate stability zone; Gas hydrates; Geothermal; Mathematical analysis; Methane; Natural gas; Sea water; South China Sea; Unconventional energy; Water depth; ISEW, South China Sea; Gas hydrate; South China Sea; Unconventional energy; Gas hydrate stability zone
• ISSN: 0920-4105; 1873-4715
• DOI: 10.1016/j.petrol.2012.01.007

Based on the relationship among water depth, sea water temperature, geothermal gradient and geological setting, the gas hydrate potential in the South China Sea (SCS) is estimated. The thickness of the gas hydrate stability zone (GHSZ) and the minimum sea water depth in order to form the gas hydrate structures I (100% CH4), II (95.9% CH4) and H (90.4% CH4) are calculated and defined by the relationship among sea water depth, seawater temperature, geothermal gradient and gas composition. The average thickness of the GHSZ in the SCS is estimated to be 225m, 270m and 365m for the gas hydrate structures I, II and H, respectively. The calculation also shows that the gas hydrate accumulation is at the water depth equal to or deeper than 600m, 400m and 300 for gas hydrate structures I, II and H, respectively. Maximum thickness area of the GHSZ in the SCS is also defined in the water depth ranging from 1200 to 2300m. By assuming that gas hydrate is distributed in one third of the calculated GHSZ area, the volume of gas hydrate reservoir is estimated to contain 1.38×1014m3, 1.41×1014m3 and 1.7 1014m3 of methane gas at the standard temperature and pressure (STP) for the gas hydrate structures I, II and H, respectively. [Display omitted] ► The South China Sea is estimated to be high gas hydrate potential. ► The maximum thickness of the GHSZ is estimated to be 365m for gas hydrate type H. ► Maximum volume of methane gas at STP is estimated to be 1.7×1014m3 in the SCS.