柴达木盆地东部第四纪水文地质条件与生物气成藏  

QUATERNARY HYDROGEOLOGY CONDITION AND RESERVOIRING OF BIOGENIC GAS IN EASTERN QAIDAM BASIN

作　　者：王明明[1] 李本亮[2] 魏国齐[2] 李景明[2] 

机构地区：[1]中国地质大学,北京100083 [2]中国石油勘探开发研究院廊坊分院,河北廊坊065007

出　　处：《石油与天然气地质》2003年第4期341-345,共5页Oil & Gas Geology

基　　金：中国石油天然气股份公司项目 :"油气预探目标评价研究"的部分成果

摘　　要：柴达木盆地东部昆仑山脉的那仁格勒河水系在乌图美仁 -台南东 -涩北 -驼峰山地区上新统 -更新统形成了那 -驼地下水循环系统 ,其两侧的达布逊湖洼陷和一里坪洼陷区属汇水盆地性质的停滞水文地质特征。台南构造以南的那 -驼地下水循环系统控制区 ,地层水显著咸化期在 3× 10 4a左右的晚更新世晚期。该期地层水溶解气量基本达到饱和。其生物气成藏机制有两种 :(1)地层水显著咸化期溶解气析出、运移、聚集成藏 ;(2 )那 -驼地下水循环系统携带南部较淡水区溶解的生物气向北部咸水区运移、析出、聚集成藏。根据水文地质特征及含油气系统特征确定船形丘构造东侧 -鸭南 -台南 -涩北为第四系生物气最有利富集区 ,其南北两侧及驼峰山 -盐湖、别勒湖南斜坡为较有利区带 ;船形丘 -鸭南 -南陵丘 -盐湖构造带为第三系生物气有利富集区带。Narengele drainage system,originated from Kunlun mountains in eastern Qaidam basin,has formed Na-Tuo groundwater circulation system in Pliocene and Pleistocene periods in Wutumeiren,east to Tainan,Sebei and Tuofengshan areas;and on its both sides,Dabuxun Lake subsag and Yiliping subsag are catchment basins characterized by stagnant hydrogeology.The formation water within the control area of Na-Tuo grounderwater circulation system to the south of Tainan structure,was distinctly salinized in the later period of late Pleistocene (about 30ka).The formation water was basically saturated with dissolved gas at that time.The reservoiring mechanism of biogenic includes two models:(1)during the distinct salinization of formation water,dissolved gas was released from the water,and then migrated, accumulated and finally became gas reservoirs;(2)the Na-Tuo groundwater circulation system,carrying the biogenic gas dissolved in the formation water with relatively low salinity in the south,migrated northward to the saline water area where the gas was then released,accumulated and became gas reservoirs.According to the characteristics of hydrogeology and petroleum system, the most favorable area for the enrichment of the Quaternary biogenic gas has been determined to be in eastern Chuanxingqiu structure-Yanan-Tainan-Sebei area,the relatively favorable area occur on both sides,north and south of the above-mentioned area and Tuofeng mountains-Yanhu and on the slope of Biele lake;the favorable belt for the enrichment of the Tertiary biogenic gas would occur in Chuanxingqiu-Yanan-Nanlingqiu-Yanhu structural belt.

关 键 词：生物气成藏 水文地质条件 气藏勘探 柴达木盆地 东部地区 第四纪 地质特征 

分 类 号：P618.13[天文地球—矿床学]