扎哈泉凹陷N_1~1沉积体系研究及有利相带预测

勘探实践表明,柴达木盆地西部扎哈泉凹陷上干柴沟组下段（N11）发育辫状三角洲-滨浅湖沉积体系,岩性油藏和致密油藏勘探潜力巨大。在岩心观察的基础上,文中通过对扎哈泉凹陷上干柴沟组下段（N11）沉积时的古地理背景分析、泥岩颜色、粒度累积概率曲线、河口坝、远砂坝砂体发育的规模、平面分布特征、变化规律和油气勘探现状等方面的系统分析。认为研究区向东至绿草滩及其以北区域辫状三角洲前缘分流水道砂和河口坝砂体发育,具有较好的油气地质条件,具备发育构造圈闭和构造背景上的岩性圈闭的地质条件,勘探潜力较大,是油气勘探的有利相带。

N11 sedimentary system study and favorable facies belt prediction in Zhahaquan Depression

Exploration practice shows that the lower interval of Upper Ganchaigou Formation has great exploration potential for lithologic reservoir and tight reservoir in Zhahaquan Depression of west Qaidam Basin,which develops braided delta-shore shallow lake sedimentary system.Based on the core observation and through the systematical analysis of paleogeographic setting,mudstone color,cumulative probability curve of grain size,mouth bar and distal bar,sand body development scale,horizontal distribution characteristics,varying regulation and the present situation of oil exploration in this paper,it is suggested that the area from the study area to the east of Wunan-Lvcaotan and its northern part develops the distributary channel and mouth bar sand body of braided delta front and has good oil-gas geological condition that can develop structural traps and lithologic traps.It is the important favorable facies belt of next step oil and gas exploration.