摘要
松辽盆地北部姚家组一段中的古土壤层可作为层序地层划分的依据。在姚家组一段中识别出3个不整合面,由盆地边缘向中心分别以河流侵蚀面—古土壤层—强烈生物作用面为标志,其下部为进积型的低位体系域三角洲砂质沉积,中部为退积型的水侵体系域三角洲砂质沉积,顶部为以泥质岩为主的加积型高水位体系域平原淤积相沉积,构成了完整的储盖组合。本文建立了受平缓坡折控制平坦古地貌背景下的大型陆相坳陷盆地层序地层学模式,认为坡折带控制岩性油藏分布,坡折带以下广泛分布的三角洲砂体成为大面积岩性油藏储集体。坡折带附近的近源区发育多层位三角洲砂岩复合体,形成了多层、厚层岩性油藏,远离坡折带的远源区分布着大面积的三角洲外前缘砂体,可形成砂岩透镜体岩性油藏和上倾尖灭岩性油藏。
Based on detailed observation and description of cores and outcrops, high-resolution sequence stratigraphy was integratedly studied in Member 1 ,Yaojia Formation in which Putaohua oil layer occurred in the northern Songliao Basin. The paleosols could be regarded as evidence of compartmentalizing sequence stratigraphy in large continental depression basins. The paper analysed features of sequence boundary surfaces and flooding surfaces, and summarized the characteristics of well logging, seismic, mineralogy and geochemistry for each key boundary. Four regional unconformities were recognized in Member 1 ,Yaojia Formation and its underlying strata, which were symbolized, from edge to center of the basin, by the rivers erosion surface, ancient soil and intense bio-active surface,respectively. The lower part for enter's accumulate was territory delta arenaceous sediment of lowstand system tract of prograding sequence, the middle part for drew back accumulate was territory delta arenaceous sediment of transgression system tract of offlap sequence, and the top deposit was mainly agillaceous territory plain siltation of highstand system tract of upgrading sequence, which constituted a complete reservoircover association. A sequence stratigraphic model was established for large-scale continental depressional basin controlled by gentle-dipped break-slope with a background of smooth ancient landform. The lithologic reservoir was constrained by the break-slopes. Beneath the breakslope,the deltaic sandbodies of large square became lithological reservoirs. Near the break- slope,muhi-layer deltaic sandbodies developed, and correspondingly, multi-layer and thick lithological reservoirs created. Far away from the break-slope,the widely distributed deltaic frontier sandbodies developed,in which the lens-shaped lithological reservoirs and pinch upword lithological reservoir formed. Therefore, it is significant for the exploration and development of Putaohua oil layer.
出处
《地质科学》
CAS
CSCD
北大核心
2009年第2期385-398,共14页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
国家"十五"岩性油气藏勘探项目(2003~2005)
国家重点基础研究发展计划(编号:2009CB219308)的部分成果
关键词
隐蔽油气藏
高分辨率层序
坡折带
葡萄花油层
油藏分布及类型
松辽盆地北部
Subtle reservoir, High-resolution sequence, Break-slope belt, Putaohua oil layer, Reservoir distribution and types,The northern Songliao Basin