摘要
酒西盆地已有半个多世纪的勘探历程 ,发现了 6个油田 ,探明石油储量约 1× 10 8t。但是对该盆地石油地质特征的认识仍然不高。通过对酒西盆地最新地震资料的解释发现 ,青西坳陷不是以往认为的整体坳陷 ,内部可划分为 3个次一级构造单元 ,两凹 (青南凹陷和红南凹陷 )夹一凸 (青西低凸起 )是其基本构造特征。青西坳陷下白垩统烃源岩主要形成于半深湖—深湖沉积环境下发育的湖侵体系域 ,虽然分布面积不大 ,但厚度很大 (在青南凹陷和红南凹陷均超过 2 5 0 0m) ,主要烃源岩赤金堡组和下沟组及中沟组是很好的烃源岩 ,有机质丰度高 ,平均有机碳含量为 1%～ 2 % ,平均热解生油潜量达 6～ 8mg/g ,氯仿沥青“A”和总烃的含量分别为 1.5‰和 0 .9‰ ,有机质类型以Ⅱ型和Ⅰ型为主 ,显微组分组成中富氢显微组分含量高 ,具有高的成烃潜力。青西低凸起西北侧的红南凹陷是生油凹陷 ,构造位置十分有利 ,青西坳陷中部应是酒西盆地深入勘探的主要目标区。图 4表 3(王孝陵摘 )
Jiuxi basin has been explored for more than half a century. Six oil fields have been discovered and 1×10 8t OOIP has been proven in the basin. However, the petroleum exploration in the basin keeps low level up to now. Based on the new seismic data obviously different from the past,the Qingxi depression of Jiuxi basin may be divided into three tectonic units: two sags (Qingnan sag and Hongnan sag) and one uplift (Qingxi low uplift) which is sandwiched between the two sags. The Lower Cretaceous source rock in the depression mainly formed in semi deep to deep lacustrine environment with a small area and large thickness (more than 2500m thick in both Qingnan and Hongnan sags). The main source rock is distributed in Chijinpu,Xiagou and Zhonggou Formations with organic carbon content from 1% to 2%, hydrocarbon generating potential ( S 1+ S 2) from 6mg/g to 8mg/g and chloroform bitumen “A” and total hydrocarbon content being 1.5‰ and 0.9‰, respectively. Organic matter is mainly composed of type II and type I kerogene containing rich perhydrous macerals and with high hydrocarbon potential. Being near the Hongnan sag, Qingxi low uplift is tectonically favorable for petroleum migration and accumulation,and should be the main exploration target in Jiuxi basin.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2001年第1期19-22,共4页
Petroleum Exploration and Development
关键词
中国
酒西盆地
油气生成
油气勘探
地质条件
生油潜力
Jiuxi basin, Structural feature, Early Cretaceous epoch, Source depression, Lake deposit, Organic matter abundance, Organic matter type, Exploration, Direction
