青藏高原冻土区活动带天然气水合物异常特征

通过对西大滩—安多油气地球化学剖面的研究表明：土壤样品酸解氢、酸解甲烷、酸解乙烷、酸解丙烷和热释汞异常的综合解释有助于对地下是否存在水合物做出推断；在烃类出现“负异常”时，可能是地下赋存水合物的标志。并结合前人文献初步建立了多年冻土区活动带天然气水合物的形成和地球化学勘查模式。分析认为土壤地球化学测量可用于在多年冻土区活动带探测水合物，但其异常解释不能完全照搬油气藏化探模式，必须把渗透性极差的冻土层对烃类气体向地表运移的影响考虑进去。

THE GAS HYDRATE ABNORMALITY IN THE MOVABLE ZONE OF THE QINGHAI-TIBET PLATEAU PERMAFROST

The study on the hydrocarbon geochemical profile of Xidatian-Anduo area indicates that comprehesive interetation to acidolysis hydrogen，acidolysis methane，dciaolysis propane，acidolysis ethane and heat-releasing mercury abnormability will be helpful to forecast if or not the hydrate exists in underground.When "negtive abnormability" occurs in hydrocarbon，it is possible that hydrate occurs in underground.According to existing literatures，the model of the formation of gas hydrate in movable zone of plateau permafrost and geochemical survey is primarily established.Analysis shows that soil geochemical survey can be used to inspect hydrate in movable zone og plateau permafrost，but in interpreting abnormability，the model of oil and gas reservoir chemical survey can not be used directly，the influence of plateau permafrost with very low permeability on gas migrating towards surface must be taken into consideration.