摘要
琼东南盆地乐东—陵水凹陷主要发育泥—流体底辟构造,根据地震资料解释成果,对乐东—陵水凹陷及周缘底辟构造的几何形态特征及成因机制进行了分析,同时探讨了底辟构造与油气聚集成藏的关系。乐东—陵水凹陷的底辟构造发育演化是区域构造应力场变化和超压系统形成演化的结果,超压系统对底辟形成起主要控制作用。两类泄压模式控制了底辟的类型和分布,根据泄压方式不同,可划分为裂缝输导泄压型底辟和断裂输导泄压型底辟。裂缝输导泄压型底辟主要沿中央峡谷水道下方呈带状分布,下超压带和中央峡谷水道的空间耦合是该底辟带形成的主要因素。断裂输导泄压型底辟主要沿乐东—陵水凹陷南、北两侧断裂带分布,下超压带和基底断层活动导致塑性岩层和流体集中流动上拱是该类型底辟的主要成因。乐东—陵水凹陷勘探实践表明,底辟和断裂是油气垂向运移的主要通道,底辟作用形成的相关构造圈闭和岩性圈闭是该地区值得关注的有利勘探目标。
Mud-fluid diapir structures are developed in the Ledong-Lingshui sag in the Qiongdongnan Basin. Based on seismic interpretation result, the geometric morphology and genetic mechanism of the diapir structures in the Ledong-Lingshui sag and its periphery were analyzed, and the relation between the diapir structures and hydrocarbon accumulation was discussed. The development and evolution of the diapir structures in the Ledong-Lingshui sag is the result of the changes of regional tectonic stress field and the formation of over pressure system. The over pressure system is the major factor controlling on the formation of the diapir structures. Two types of pressure relief modes control the types and distribution of the diapir structures; therefore,the diapir structures can be divided into two types: transportation and pressure relief through fractures, transportation and pressure relief through faults. The diapir structures formed by transportation and pressure relief through fracturesare chiefly distributed in banded style along the lower part of the central canyon channel, and the spatial coupling of the lower over pressure zone and the central canyon channel is the major element for forming this diapir belt. The diapir structures formed by transportation and pressure relief through faults are chiefly distributed along the faulted belts at northern and southern sides of the Ledong-Lingshui sag, and the centralized flowing and upwarping of plastic rock and fluid caused by the lower over pressure zone and the base fault activity are the major genesis of such diapir structures. The exploration practice in the Ledong-Lingshui sag indicates that the diapirs and faults are the major pathways for vertical hydrocarbon migration, the structural traps and lithological traps associated with diapirism are the favorable exploration targets that should be concerned in this area.
作者
杨东升
赵志刚
杨海长
曾清波
韩银学
赵钊
王龙颖
郭帅
孙钰皓
Yang Dongsheng;Zhao Zhigang;Yang Haizhang;Zeng Qingbo;Han Yinxue;Zhao Zhao;Wang Longying;Guo Shuai;Sun Yuhao(CNOOC Research Institut)
出处
《中国石油勘探》
CAS
北大核心
2018年第3期64-73,共10页
China Petroleum Exploration
基金
国家科技重大专项"南海深水区油气资源潜力与大中型油气田勘探方向"(2016ZX05026007)
国家自然科学基金项目"南海深海地质演变对油气资源的控制作用"(91528303)
关键词
乐东—陵水凹陷
泥—流体底辟构造
超压系统
底辟作用
油气成藏
Ledong-Lingshui sag
mud-fluid diapir structure
over pressure system,diapirism,hydrocarbon accumulation