Computation of Thickness of Gas Hydrate Stability Zone and Potential Volume of Gas Hydrate in South China Sea
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摘要: 中国的南海一直被人们认为蕴藏着丰富的天然气水合物资源,综合中国南海的水深、地热梯度及底部水温等地质资料,运用VisualBasic.Net编程分析在该海域范围内天然气水合物稳定带厚度,讨论其分布特征,并以此来评估该区域的水合物资源量.结果表明当地热梯度为0.06℃/m,在区域1中可能存在天然气水合物,其稳定带的最大厚度可达400 m,天然气水合物分布较为规则,从外向内逐渐增厚.但在区域2中由于受到水深和地热等因素的影响不存在天然气水合物,此时天然气水合物的资源量约为0.55×104 km3;当地热梯度随机取值时,该区的天然气水合物资源量约为0.57×104 km3.通过对地热梯度取不同的值,估算得到在该研究区天然气水合物的资源量约为0.6×104 km3.Abstract: The South China Sea has long been regarded as abundant in the resource of gas hydrate. Having integrated the data of the depth of the overall South China Sea,and that of geological conditions such as geothermal gradient and bottom water temperature,a Visual Basic.Net program is proposed to compute the thickness of the gas hydrate stability zone and potential volume of gas hydrate in the region. We find that in area 1 gas hydrate may exist,and the maximum thickness of the gas hydrate stability zone is about 400 m when geothermal gradient is 0.06 ℃/m. The distribution of gas hydrate is very equal,the trend is being thicker from outside to inner. But in area 2 there is a lack of gas hydrate because of the depth,geothermal gradient and other factors,and the potential volume of gas hydrate is about 0.55×104 km3. When the geothermal gradient is random,the potential volume of gas hydrate is about 0.57×104 km3. Through getting the different geothermal gradients,we can calculate that the potential volume of gas hydrate in the South China Sea is about 0.6×104 km3.
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表 1 南海天然气水合物稳定带厚度估算部分数据
Table 1. Part of data used in the computation of the thickness of gas hydrate stability zone in South China Sea
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