泌阳凹陷基于层序地层格架的油气成藏模式

泌阳凹陷层序地层研究表明，油气藏与层序地层体系域关系密切:南部陡坡带上倾尖灭油气藏主要位于低位和高位体系域中;中央凹陷带岩性透镜体油气藏主要是低位特殊地质体和高位白云岩缝洞储层构成的油气藏;北部缓坡带与层序地层密切相关的是地层不整合油气藏及断层-不整合油气藏，断层-岩性、断鼻等油气藏在高位体系域较发育。此外，北部斜坡区存在低位三角洲以及湖扩体系域地层超覆油气藏和高位滑塌岩性体油气藏。结合泌阳凹陷层序地层特点和各种类型油气藏分布规律，总结了泌阳凹陷基于层序地层格架的油气藏成藏模式。油气成藏模式表明,深凹区环盐湖带是当前岩性-地层类隐蔽油气藏勘探的重点领域。这类隐蔽油气藏主要有低位特殊地质体、低位三角洲、湖扩体系域地层超覆、高位白云岩缝洞油气藏、高位浊积体、高位断层-岩性等潜在的岩性-地层油气藏。

The Model for Reservoir Formation Within the Sequence Stratigraphic Framework in Biyang Depression

Sequence stratigraphy research in Biyang depression indicates,the subtle reservoirs are related to system tracts of sequence stratigraphy,the updip pinchout reservoirs in south steep slope zone are mainly within the lowstand and highstand system tracts(LST and HST),the lithologic lens in the central depression are mainly abnormal geobody of LST and dolomite fracture reservoirs,the reservoirs in the north gentle slope are mainly stratigraphic unconformity,fault unconformity,fault-lithology,fault-nose reservoirs of HST,there also exist delta of LST,stratigraphic overlap of expanding system tracts(EST) and slump lithology of HST.Based on the sequence stratigraphy characteristics and the distribution of various types of reservoirs,the model for reservoir formation within the sequrence stratigraphic framework in the Biyang depression is established.The model indicates that the area around the salt lake zone is the keystone domains of subtle reservoirs exploration such as lithological/stratigraphic reservoirs,which include the geobody of LST,delta of LST,stratigraphic overlap of EST,dolomite fractures of HST,turbidite of HST and fault-lithology of HST.