柴达木盆地西部中生界原型盆地恢复  

Reconstruction of the Mesozoic Proto-type Basin in the West Qaidam Basin

作　　者：段宏亮[1] 钟建华[1] 马锋[1] 张跃中[2] 李勇[1] 温志峰[3] 

机构地区：[1]中国石油大学资源与信息学院,山东东营257061 [2]青海油田公司勘探开发研究院,甘肃敦煌736202 [3]胜利油田地质科学研究院,山东东营257061

出　　处：《沉积学报》2007年第1期65-74,共10页Acta Sedimentologica Sinica

摘　　要：勘探实践表明,对柴达木盆地西部中生界原型盆地认识不够,是导致该区侏罗系油气勘探难以取得重大突破的主要原因。以古流分析为主要手段,结合地表露头及地震解释资料研究认为,中生界在古阿拉巴斯套山与古昆仑山间发育一个大的近EW向展布的内陆山间坳陷(古泛茫崖坳陷)。坳陷演化可分为早—中侏罗世和晚侏罗世—白垩纪两个阶段,分别对应发育了伸展断陷和挤压坳陷两种原型盆地类型。早、中侏罗世,阿尔金山尚未隆升,为主要沉积区。沉积环境比较动荡,沉积物以暗色含煤建造为主。沉积中心在现今的阿尔金山区,坳陷西北部边界越过阿尔金山区与塔东南地区相通;东北部边界位于阿拉巴斯套山前;南部边界在煤沟—采石岭—黑石山—月牙山一线。晚侏罗世—白垩纪,阿尔金山快速隆升为物源区,开始分割塔东南和柴达木盆地西部沉积。坳陷沉积物以干旱气候下的红色粗碎屑岩建造为主,沉积、沉降中心由阿尔金山区向盆地内部发生迁移,南部边界已迁移至阿拉尔—红柳泉—红沟子—月3井一带。该研究对柴达木盆地资源潜力评价及勘探部署具有重要意义。In the exploration practice, it is found that the inadequate knowledge about the Mesozoic proto - type basin in the western Qaidam basin slowed the oil and gas exploration in this area. Based on analyzing the paleocurrents, combining the Mesozoic outcrops and seismic interpretation data, the Mesozoic proto-type of the western Qaidam basin is recovered in this paper. There developed an intermountain depression between the old Alabasitaomountain and the Kunlun mountain, which trending is E-W. The evolution of the depression includes two stages： the Early-Middle Jurassic and the Late Jurassic-Cretaceous, corresponding developed two proto-type basins. The Early-Middle Jurassic basin is fault basin type and the Late Jurassic-Cretaceous depression type. During the Early-Middle Jurassic, the Altyn Tagh was not uplifted. The deposition was coal bearing formation. The depocenter was in the present Ahyn Tagh region. The northwest edge of the depression crossed the Ahyn Tagh and conjoined with the Southeast Tarim basin, the northeast edge was ended in the Alabasitao region, and the south was restricted along the Hongliuquan-Meigou- Heishishan-Yueyashan. During the Late-Cretaceous, the Ahyn Tagh uplifted rapidly and became a province. The deposition was coarse clastic formation. The subsidence and sedimentation area migrated gradually towards inside basin because of the uplift of the Altyn Mountain. The south edge of the depression was along the Alaer-Hongliuquan- Honggouzi-Yue3jing.

关 键 词：柴达木盆地西部 阿尔金山 中生界 原型盆地 古流 

分 类 号：TE121[石油与天然气工程—油气勘探]