南海珠江深水扇系统的微观内幕结构研究

Microscopic architectures of the Zhujiang deep-water fan systems in the South China Sea

关键词:  南海珠江  白云凹陷  深水扇  微观内幕结构

Key words:  Zhujiang  South China Sea  Baiyun depression  deep-water fan  microscopic architecture

摘要:

本文首次探索在以二维地震资料为主的条件下开展深水扇系统的微观内幕研究。结果表明:在珠江口盆地白云凹陷中的南海珠江深水扇系统中能较好地由浅至深识别出多套地层(尤其是浅部地层)中存在的多种类型的深切谷、峡谷、水道,各有不同地质成因机制。能识别的典型扇体微观结构类型包括丘形体、席状体、水道化沉积及朵叶体等,往往分别指示某些特殊的沉积环境,并且最可能构成潜在的深水油气圈闭的良好储层。在二维地震资料条件下容易识别的深水扇系统微观内幕结构类型比较有限,在空间上追踪典型微观内幕结构也相对比较困难,但是若能全面认识区域构造及沉积背景,综合利用相关资料减少对地震反射结构解释的多解性,就有望对扇体的微观内幕结构进行深入剖析,深化对扇体的地质认识,从而指导油气勘探。

Abstract:

The microscopic architectures of the deep-water fan systems are explored for the first time with the aid of 2-D seismic data. A variety of incised valley, canyon and channel of varying origins have been distinguished in several successions of strata (especially the shallow strata) in the Zhujiang deep-water fan systems in the South China Sea. The representative microscopic architectures include the mounds, sheets, channelized deposits and lobes that may indicate some particular sedimentary environments and constitute potential excellent reservoirs of deep-water oil and gas traps. Since the microscopic architectures of the deep-water fan systems recognizable only with the aid of 2-D seismic data are rather limited and difficult to be traced in space, the regional tectonic and sedimentary data must be referenced in using seismic reflection configurations to interpret the microscopic architectures of the deep-water fan systems and further improve our knowledge of deep-water oil and gas exploration.