摘要
辽西低凸起北段JZ20构造区东二下亚段湖底扇岩性主要为中-细粒砂岩,颗粒分选中等,孔隙发育,可分为内扇、中扇和外扇亚相,其中内扇、中扇多为优质储层,表现为单一水道、辫状水道的特征,自然伽马(GR)曲线表现为微齿化箱形和齿化状钟形,地震剖面上表现为下切反射和叠瓦状反射特征;湖底扇受物源和触发机制等多因素制约,物源来自古辽河水系的大型辫状河三角洲前缘砂体,受强烈的正断层活动、斜坡坡度与湖浪扰动等影响,原始沉积物沿着斜坡向下滑塌,在深湖-半深湖中形成扇形沉积体;辽西低凸起北段湖底扇紧邻辽中富生烃凹陷、储盖组合好、运移通畅,具有较好的勘探潜力。
The lithology of sub lacustrine fan is mainly composed of medium-grained to coarse-grained sandstones of middle sorting and pore development. Sub lacustrine fan facies can be divided into three sub-facies: inner fan, middle fan and outer fan. Inner fan and middle fan is mainly high-quality reservoirs, composed by one main channel and braided channel, mainly manifested as minimal zigzag and zigzag bell-shaped curves of gamma logging curve in the logging facies, gully-shaped and imbricate arrangement in the seismic section. Sub lacustrine fan formation in the area was mainly controlled by multivariate as the provenance and the trigger mechanism. Large scale braided river deltas front sand bodies that were from ancient Liaohe river system were a basic geological condition for the formation of sub lacustrine fan. Due to the strong normal faulting, the gradient of slope and the action of waves disturbance, original sediments slumped along with slope, and deposited in the semi deep-deep lacustrine facies. Sub lacustrine fan in the north of Liaoxi low uplift has a certain petroleum exploration potential based on the nearby hydrocarbonrich source rocks, having good reservoir rock, good caprock association, and good migration.
出处
《石油地质与工程》
CAS
2018年第4期35-37,41,共4页
Petroleum Geology and Engineering
基金
国家"十二五"重大科技攻关项目(2011ZX05023-002)
关键词
辽西低凸起
东二下亚段
湖底扇
沉积特征
成因机制
Liaoxi low uplift
lower Ed2 formation
sub-lacustrine fan
sedimentary characteristics
genetic mechanism