勘查地球化学方法适用于勘查天然气水合物的依据

人们一直关注勘查地球化学（即化探）方法能否适用于以固体形式赋存于孔隙沉积地层中的水合物介质。从水合物地质学和水合物勘探地震学提供的烃类物质微渗漏的事实、水合物化探自身理论和国际ODP 204航次水合物钻井样品的地球化学分析结果以及南海水合物研究区的化探实践3个方面探讨并阐述了勘查地球化学方法在水合物勘查中的适用性，化探方法能够从海底沉积物的痕量化学组分的分布上追踪水合物存在的有利证据。

Foundation of Geochemical Prospecting Method Applying to Gas Hydrate Prospecting

It is always concerned that whether the geochemical prospecting can be applied to the study of the solid form of the hydrate medium deposited in porous sedimentary stratum. This study discussed the application of geochemical prospecting from 3 aspects: (1) the fact of hydrocarbon microseepage provided by the geology and seismic exploration of hydrate,(2) the hydrate geochemical prospecting theory, the Xisha Trough geochemical prospecting and the geochemical analysis results of ODP leg 204 hydrate drilling samples,and (3) the geochemical practice in the researching zone of the South China Sea. The results show that the geochemical prospecting can provide the favorable evidences of hydrate existence from the distribution of trace elements of the seafloor sediments.