摘要
作为我国多年冻土发育的主要地区之一,漠河地区具有天然气水合物形成的良好条件,发育了天然气水合物的成藏系统。漠河地区发育有多年冻土,一般厚20~80 m,地表温度-0.5℃^-3.0℃,地温梯度1.6℃/100m,具有与已发现天然气水合物的美国阿拉斯加北坡Prudhoe湾、西伯利亚Messoyakha和我国祁连山木里地区类似的地温条件;漠河盆地中侏罗统厚达千余米的暗色泥岩,204.66×1012m3的烃类气体生成量,乃天然气水合物形成的重要母质和气体来源;盆内隆起、凸起及其边界断裂和地层裂缝,分别构成了水合物形成聚集的良好圈闭和烃类运移系统,其中的砂岩、粉砂岩为良好储层,上部的巨厚泥岩为封盖层。进一步看,漠河盆地发育的大量方解石脉、后生黄铁矿及钻探烃类异常等天然气水合物赋存标志。所有这些,无不显示该区域天然气水合物形成的良好条件及巨大成藏潜力。
Mohe region,one of the permafrost in China,with gas hydrate petroleum system developed in it,shows the good accumation conditions of gas hydrate.Permafrost,with 20~80 m in thickness,occurs in Mohe area.Mohe permafrost is-0.5℃～-3.0℃ of the ground surface temperature,1.6℃/100m of geothermal gradient,and exhibits a geotherm condition similar to Prudhoe bay in Alaska,Messoyakha in Siberia,and Muli area in Qilian Moutain.204.66×1012 cubic meters of hydrocarbon gas of Mohe basin,generating from 1000 or more meters of dark mudstones,is provided for gas hydrate formation.In Mohe basin,the uplifts and salients,bounded by faults,which,combined with fissures in rocks,make up conduits for hydrocarbon gas migration,act as trap for gas hydrate accumulation.The sandstones,siltstones made of the traps,with the mudstones of it for seal,are reservoirs for gas hydrate accumulation.Furthermore,calcite veins,epigenetic pyrite are prevalent in the cores,a great amount of hydrocarbon gas effused during the drilling.All of the mentioned above exhibit the good condition of gas hydrate and its great potential of accumulation.
出处
《地质学报》
EI
CAS
CSCD
北大核心
2011年第9期1536-1550,共15页
Acta Geologica Sinica
基金
国土资源大调查项目(编号GZHL20110317)资助的成果
关键词
天然气水合物
多年冻土区
赋存标志
石油地质
漠河
gas hydrate
permafrost area
indications of occurrence
petroleum geology
Mohe in China
