摘要
中亚地区阿姆河盆地盐下侏罗系碳酸盐岩发现大型—巨型天然气藏,天然气中硫化氢(H_(2)S)含量高,天然气分布规律十分复杂。为了进一步提高该区高含硫气藏勘探开发效益,综合研究了高含硫气藏地质特征、时空分布、天然气组分特征,分析了高含硫天然气藏类型和成因,总结了高含硫天然气富集规律。研究结果表明:①盆地内H_(2)S含量与上侏罗统硬石膏沉积和成岩有密切关系,高含硫气藏根据天然气中H_(2)S来源可分为原地生成、异地生成和混合生成3类,其中以原地生成高含硫天然气藏为主,规模最大;②原地生成高含硫天然气藏可细分为台内—台缘相带石膏—石灰岩互层型、台缘斜坡相带高能礁滩型和台缘斜坡—盆地相带断控型,异地生成高含硫气藏可分为横向运聚型和纵向运聚型;③生烃坳陷和碳酸盐岩沉积相带控制了高含硫天然气富集程度,其中碳酸盐岩台缘相带是最为富集区带,通源断层可以进一步促进高含硫天然气的成藏富集,生烃坳陷内具有大型古隆起背景的继承性构造是最有利的勘探目标。结论认为,通过高含硫天然气成因和富集规律的认识,指出应加强盆地生烃坳陷区盐下侏罗系具有基底古隆起区和大型断裂区高含硫碳酸盐岩气藏的勘探。
Large and giant high-sulfur gas reservoirs have been discovered in the pre-salt Jurassic carbonate rocks of the Amu Darya Basin in Central Asia with high H_(2)S contents in natural gas and quite complicated gas distribution.To further improve the exploration and development benefit of high-sulfur gas reservoirs in this area,this paper comprehensively studies the geological characteristics,spatiotemporal distribution and natural gas compositions of these high-sulfur gas reservoirs,analyzes the types and origins of high-sulfur gas reservoirs,and summarizes the enrichment patterns of high-sulfur gas.The following results are obtained.First,the H_(2)S content in the Amu Darya Basin is closely related to the deposition and diagenesis of Upper Jurassic anhydrite.According to the source of H_(2)S in natural gas,high-sulfur gas reservoirs can be divided into three types,i.e.,in-situ generation,allochthonous generation and mixed generation,among which,in-situ generation is dominant.Second,the in-situ generated high-sulfur gas reservoirs can be subdivided into the gypsum interbedded with limestone gas reservoir in intraplatform–platform margin facies zones,the high-energy reef–shoal gas reservoir in platform marginal slope zones,and the fault controlled gas reservoir in platform marginal slope–basin facies zones.The allochthonous generated high-sulfur gas reservoirs can be subdivided into the lateral migration and accumulation gas reservoir and the vertical migration and accumulation gas reservoir.Third,the enrichment degree of high-sulfur gas is controlled by hydrocarbon generating depressions and carbonate sedimentary facies zones,and the highest enrichment degree occurs in the carbonate platform margin facies zones.The faults connecting source rocks can further promote the accumulation and enrichment of high-sulfur gas,and inherited structures with large paleouplift background in the hydrocarbon generating depressions are the most favorable exploration targets.It is concluded,by understanding the formation mechanisms and enrichment patterns of high-sulfur gas,that exploration shall focus on the pre-salt Jurassic high-sulfur carbonate gas reservoirs with basement paleo-uplifts and large fault zones in the hydrocarbon generating depressions of the Amu Darya Basin.
作者
张良杰
张兴阳
王思琦
王红军
张培军
郭春秋
蒋子文
罗敏
ZHANG Liangjie;ZHANG Xingyang;WANG Siqi;WANG Hongjun;ZHANG Peijun;GUO Chunqiu;JIANG Ziwen;LUO Min(PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China;CNPC<Tajikistan>Bokhtar Company,Beijing 100083,China;CNPC<Turkmenistan>Amu Darya River Company,Beijing 100083,China)
出处
《天然气工业》
EI
CAS
2024年第11期60-71,共12页
Natural Gas Industry
基金
中国石油天然气股份有限公司科技项目“塔吉克复杂逆冲含盐盆地深层超深层油气地质理论与关键技术研究”(编号:2024DJ99)。
关键词
阿姆河盆地
侏罗系
碳酸盐岩
高含硫
天然气
富集规律
Amu Darya Basin
Jurassic
Carbonate rock
High sulfur
Natural gas
Enrichment pattern
