桂中坳陷西北部桂页1井泥盆系页岩气聚集条件研究  

Accumulation conditions of Devonian shale gas in Well GY 1 in northwestern Central Guangxi depression

作　　者：苑坤[1] 方欣欣[2] 闻涛[3] 林拓[1] 石砥石[1] 包书景[1] 周志[1] 张聪[1] 

机构地区：[1]中国地质调查局油气资源调查中心 [2]中国地质科学院地质力学研究所 [3]中国石油化工股份有限公司勘探分公司

出　　处：《中国石油勘探》2017年第4期90-97,共8页China Petroleum Exploration

基　　金：中国地质调查局项目"滇黔桂上古生界页岩气战略选区调查"(DD20160196)

摘　　要：桂中坳陷西北部普遍发育的泥盆系页岩,是滇黔桂地区页岩气勘探突破的重点。为查明该地区页岩气聚集条件及资源潜力,以桂中坳陷首口单井完整钻遇泥盆系各套主力页岩层的桂页1井岩心资料为研究对象,通过均匀取样(采样间隔2m),对300余块岩心样品进行有机地球化学、岩石矿物学等实验分析,认为桂中坳陷西北部泥盆系页岩具有厚度大(470~1300m)、有机碳含量高(0.23%~10.63%)、热演化程度高(R_o为1.88%~2.83%)等特点,有利于页岩气的生成和聚集;另外,其脆性矿物含量高、有机质孔及微裂缝发育等特点显示出页岩层段良好的可改造性。然而,经过多期构造运动改造,断裂活动对该区的页岩储层有一定破坏作用,对页岩的含气性有较大影响。从勘探潜力来看,通过分析泥盆系3套主力页岩层(榴江组、罗富组、纳标组)的各项参数指标,认为榴江组下段从有机地球化学特征、物性特征、成藏条件等方面均相对有利,是该区页岩气勘探的重点层段。The Devonian shale widely distributed in northwestern Central Guangxi depression is the primary target for seeking breakthrough of shale gas in the Yunnan-Guizhou-Guangxi region. In order to identify the accumulation conditions and potentials of shale gas in this region, more than 300 core samples were evenly taken （at sampling interval of 2 m） in Well GY 1 for organic geochemistry and rock mineralogy analysis. Well GY 1 is the first exploration well drilled through all Devonian shale gas formations in the Central Guangxi depression. The analysis results indicate that the Devonian shale is characterized by big thickness （470-1300 m）, high TOC （0.23%-10.63%） and high maturity （Ro=1.88%-2.83%）, which are favorable for the generation and accumulation of shale gas. Moreover, the shale has high content of brittle minerals and presence of organic pores and micro-fractures, implying the high probability of the shale gas reservoir to be stimulated. However, faulting activities during multi-stage tectonic movements damaged the shale reservoir, especially the gas-bearing potential. In view of exploration potentials, analysis of three sets of major shale gas formations （Liujiang Formation, Luofu Formation and Nabiao Formation） indicates that the Lower Liujiang Formation is the primary shale gas exploration target for its relatively favorable organic geochemical and physical properties and hydrocarbon accumulation conditions.

关 键 词：桂中坳陷 泥盆系 页岩 页岩气 储集条件 

分 类 号：TE2[石油与天然气工程—油气井工程]