石油实验地质2025，Vol.47Issue(6)：1282-1294,13.DOI:10.11781/sysydz2025061282
川南泸州地区龙马溪组一段有机质页岩裂缝发育特征及有利区评价
Development characteristics and favorable area evaluation of organic-rich shale fractures in first member of Longmaxi Formation,Luzhou area,southern Sichuan Basin
摘要
Abstract
The shale gas in the first member of the Silurian Longmaxi Formation in the southern Sichuan Basin exhibits promising potential for exploration and development.To clarify the influence of the development characteristics of natural fractures in shales on shale gas enrichment patterns,the organic-rich shales in the first member of the Longmaxi Formation in the Luzhou area,southern Sichuan Basin were selected as the study objects.Utilizing drilling cores,thin-section identification,and geophysical well logging data,this study investigated the types and development characteristics of fractures in the Longmaxi Formation shales in the study area through comprehen-sive geological analysis methods.The results showed that the fracture types were mainly structural fractures(shear fractures)and non-structural fractures.Structurally,the degree of fracture development was negatively correlated with the distance from faults,with fractures being well-developed in the anticline areas and less developed in the syncline areas.In terms of non-structural factors,fracture density was positively correlated with total organic carbon content(≥2%)and brittle mineral content(≥44%).The gas-bearing capacity of organic-rich shales in the study area was affected by factors such as the degree of fracture filling,the relationship between the current in-situ stress direction and the fracture strike,and the degree of fracture dispersion.Among these,partially filled and unfilled fractures,fractures intersecting with the current maximum principal stress at high oblique angles,and fracture networks with scattered strikes significantly enhanced the gas-bearing capacity of shales.This study divided the effective fractures in the organic-rich shales of the first member of the Longmaxi Formation in the Luzhou area of the southern Sichuan Basin into 6 ClassⅠfavorable areas and 7 ClassⅡfavorable areas.It iden-tified the anticline areas and areas adjacent to fault zones as the exploration target areas.These findings provide important theoretical support and practical guidance for the exploration and development of shale gas in the Luzhou area of the southern Sichuan Basin.关键词
裂缝发育特征/页岩含气性/有机质页岩/龙马溪组/泸州地区/四川盆地Key words
fracture development characteristics/shale gas-bearing capacity/organic-rich shale/Longmaxi For-mation/Luzhou area/Sichuan Basin分类
能源科技引用本文复制引用
范存辉,刘胜军,唐林吉,郝挺,刘勇,刘文平,赵圣贤,张成林,李博,谢圣阳,乔琳..川南泸州地区龙马溪组一段有机质页岩裂缝发育特征及有利区评价[J].石油实验地质,2025,47(6):1282-1294,13.基金项目
"十三五"国家科技重大专项"长宁—威远页岩气开发示范工程"(2016ZX05062)资助. （2016ZX05062）
