摘要
对桂中坳陷泥盆系泥页岩的成藏条件进行了分析,认为区内泥页岩主要发育在中-下泥盆统,该层系泥页岩分布面积广,沉积厚度大,有机碳含量高,泥页岩层段埋藏深度适中,具备页岩气成藏的基本条件。但桂中坳陷历经多期强烈的构造改造,断裂发育,部分地区还伴随岩浆活动,导致桂中坳陷页岩气藏的保存条件较差,而断裂和岩浆活动影响相对较小的中西部地区是桂中坳陷页岩气勘探的有利方向。认为在有机质演化程度高,构造运动复杂的地质背景下,页岩气的勘探必须强调保存条件,保存条件将会是制约中国页岩气藏勘探的关键因素之一。
Using samples from typical sections, drilling data and geochemical information from the Devonian black shale in Guizhong depression of central Guangxi, the authors analyzed the accumulation condition of shale gas reservoirs. The results demonstrate that there exist two suites of exceUent marine source rocks in the middle and lower Devonian strata of Guizhong depression, which are characterized by large thickness and extensive distribution, high abundance of organic matter and moderate buried depth, thus possessing basic conditions for the formation of shale gas reservoirs. However, the preservative condition of shale gas is very poor because of the subsequent multistage severe tectonic movements as weU as the development of faults and magmatic activities in some areas. Therefore, the central and western areas of Guizhong depression with integrated strata, underdeveloped faults and magmatic activities seem to be the favorable places for shale gas exploration. It is suggested that the preservation condition is very important in exploring shale gas resources under the conditions of high organic thermal evolution extent and subsequent multistage severe tectonic movements. The preservation condition is one of the key factors for shale gas exploration in China.
出处
《中国地质》
CAS
CSCD
北大核心
2013年第2期430-438,共9页
Geology in China
关键词
页岩气
成藏条件
保存条件
泥盆系
桂中坳陷
shale gas
accumulation condition
preservation condition
Devonian
Guizhong depression
