摘要
文章利用南海所积累的大量热流、海底温度和地温梯度数据,针对地温梯度的变化,对地温梯度数据进行了初步校正。分情况研究了纯甲烷,甲烷、乙烷、丙烷混合物分别在纯水、海水条件下形成的天然气水合物在南海的可能分布范围;进而对影响天然气水合物分布的影响因素进行了讨论。研究表明,随着天然气中重烃含量的增加,孔隙水盐度的降低,水合物稳定带在平面上的分布范围越来越大,水合物稳定带的厚度也越来越大。比较而言,气体组成的影响要比孔隙水盐度的大。同时,天然气水合物稳定带的厚度与热流有一定的负相关关系。在南海2000m水深范围之内,由于受海底温度的控制,水合物稳定带的厚度与水深呈明显的正相关关系。
Based on the available data of heat flows, sea-bottom temperatures and geothermal gradients, this paper studied the potential distribution of natural gas hydrates in the South China Sea, and discussed their influential factors. The authors have reached the conclusion that natural gas hydrate stability zone will be broadened and their thickness will become thicker with the increase of heavy hydrocarbon gas and the decrease of the pore water salinity. Comparatively speaking, the influence of the natural gas components is stronger than that of the pore water salinity. Meanwhile, the thickness of natural gas hydrate shows certain negative correlation with the heat flow value. Within the water depth of 2 000 m, however, the thickness of natural gas hydrates assumes obvious positive correlation with the water depth, which is attributed to the controlling role of the sea floor temperature.
出处
《矿床地质》
CAS
CSCD
北大核心
2005年第4期388-397,共10页
Mineral Deposits
基金
国土资源部项目(编号:SHW01_01_03)
国家863项目(编号:2001AA611020_03)联合资助
关键词
地质学
天然气水合物
稳定带
分布
南海
geology, natural gas hydrates, stability zone, distribution, South China Sea
