摘要
库车坳陷东部致密砂岩气是库车天然气勘探开发的重要接替领域。由于研究区致密砂岩气藏的复杂性,目前对该区气藏的特征与分布规律还不十分清楚。从气藏的基本特征研究入手,通过对依南2气藏的解剖研究,认为本区致密砂岩气藏具有砂岩储层致密、微裂缝发育、异常高压发育、含气饱和度低等特征。其中孔隙度低、渗透率高是该区致密砂岩气藏的独特特征;排驱压力与喉道半径对气藏的成藏效率具有重要的影响;致密砂体中发育的裂缝对天然气的聚集和富集具有重要的影响和控制作用,表现为早期微裂缝提高了天然气的充注聚集效率,晚期构造缝控制了天然气富集带的分布。气藏类型为晚期成藏、持续充注的异常高压致密砂岩气藏。
The tight sandstone gas of eastern Kuqa Depression is an important replacement area for devel- opment and exploitation of West-East natural gas transmission. Due to the complexity of the tight gas res- ervoir, understanding the distribution law of gas reservoir in the area of Kuqa Depression is very difficult. This article＇s purpose is to analyze the Yinan 2 reservoir by the basic characteristics, in order to clearly un- derstand the characteristics and enrichment rule of tight sandstone gas reservoir. Through detail study on the Yinan 2 reservoir, we consider that this tight sandstone gas reservoir is characterized by dense sand- stone reservoir, well developed microfractures, abnormal high pressure, and low gas saturation. Among them, low porosity but high permeability is the unique property. Source reservoir pressure difference and throat radius vastly influence the gas accumulation efficiency. We point out that the early stage cracks de- veloped in the tight sandstone can easily lead to form the relatively high gas saturation, however the late stage crack control the distribution law of the natural gas enrichment zones. Type of the gas reservoir is an abnormal high pressure tight sandstone gas reservoir resulted from late accumulation and ongoing filling.
出处
《地质科技情报》
CAS
CSCD
北大核心
2014年第2期116-122,共7页
Geological Science and Technology Information
基金
国家重大专项项目下属"大气田形成条件
成藏机制与富集规律研究"课题(2011ZX05007-002)
关键词
库车坳陷东部
依南2气藏
致密砂岩气
喉道半径
含气饱和度
异常高压
eastern Kuqa Depression
Yinan 2 gas reservoir
tight sandstone gas
throat radius
gas saturation
abnormal high pressure
