摘要
为评价湘西北地区下志留统龙马溪组页岩气聚集条件及含气性,优选并实施钻探了永页1井,揭示的龙马溪组暗色泥页岩厚度131.2 m,其中黑色页岩19.3 m.永页1井龙马溪组黑色页岩具有有机碳含量高（平均为2.0％）、成熟度适中（等效Ro平均为2.4％）、脆性矿物含量高（石英含量平均为50.3％）、黏土矿物含量低（平均为31.3％）、孔隙度低（平均为1.7％）等特征,具有良好的页岩气聚集条件;尽管等温吸附含气量平均可达2.52 m^3/t,但现场解析总含气量很低,推测这是黑色页岩埋深较浅且湘西北地区晚期构造活动强烈、保存条件不好所致;黑色页岩的沉积厚度反映了该井位于龙马溪组深水陆棚沉积的边缘相带,而更靠近沉积中心的花垣—保靖—龙山一带,黑色页岩厚度可达30～40m,是该区龙马溪组页岩气下一步勘探的主要区域.
For evaluating accumulation conditions and gas content characteristics of the Lower Silurian shale in northwestern Hunan province,Well Yongye-1 was optimally selected and drilled,and it revealed the Lower Silurian dark shale of 131.2 m in thickness,including 19.3 m thick black shale.The black shale of Longmaxi formation is characterized by high TOC （2.0％ in average）,medium organic maturity （2.4％ in average）,high brittle mineral content （50.3％ quartz in average）,low clay content （31.3％ in average） and low porosity （1.7％ in average）,showing good shale gas accumulation conditions.Although the the result of isothermal adsorption simulation test shows that the black shale have a good adsorption capacity （2.52 m^3/t in average）,the gas content from well site desorption test is very low.This is presumably due to the shallow depth of it,the intense tectonic activity in northwestern Hunan province and the poor preservation condition.The sedimentary thickness of the black shale reflects that The sedimentary environment of Well Yongye-1 is located at the edge of deep water shelf,so Huayuan-Baojing-Longshan areas with 30～40 m thick black shale that are close to the sedimentary center could be as the targets for further shale gas exploration in this area.
出处
《新疆石油地质》
CAS
CSCD
北大核心
2014年第5期507-510,共4页
Xinjiang Petroleum Geology
基金
国家自然科学基金(41102088)
国家科技重大专项(2009GYXQ-15)
关键词
湘西北
龙马溪组
永页1井
页岩气
聚集条件
含气性
northwestern Hunan province
Longmaxi formation
Well Yongye-1
shale gas
accumulation condition
gas-bearing property
