摘要通过岩心和测井资料分析,系统地研究了松辽盆地中央坳陷滨北地区上白垩统青山口组的沉积特征;采用单因素分析多因素综合作图法,编制出了研究区上白垩统青山口组各亚段的砂岩含量、暗色泥岩含量和紫红色泥岩含量等单因素图件,在此基础上做出沉积相图,深入分析了研究区沉积演化规律。研究表明,青山口组主要发育三角洲和湖泊2种沉积相,进一步分为三角洲平原、三角洲前缘、滨浅湖和半深湖-深湖4种沉积亚相。从研究区边缘到中心,沉积相类型由三角洲平原亚相渐变为三角洲前缘、滨浅湖和半深湖-深湖亚相;自下而上由半深湖-深湖亚相逐渐变为滨浅湖、三角洲前缘、三角洲平原亚相。青山口组沉积时期可划分为青山口组沉积早期、青山口组沉积中期和青山口组沉积晚期。不同时期、不同构造单元的沉积特征表现各异,从青山口组沉积早期到青山口组沉积晚期,研究区湖盆发育总体表现出规模由大到小的特点。
The sedimentary characteristics of the Qingshankou Formation of Upper Cretaceous in Binbei area of Central Depression in Songliao Basin were systematically analyzed, based on studies of core and well-log facies. The planar distribution of sedimentary facies of different members of Qingshankou Formation and facies evolution were studied in detail, according to the single factor analysis and muhifactor comprehensive mapping method. Maps of single factors and sedimentary facies of different members of Qingshankou Formation have been compiled. The results show that during the deposition of Qingshankou Formation, mainly two types of sedimentary facies: delta and lacustrine facies, including four subfacies, i.e. delta plain, delta front, shore-shallow lacustrine and semi-deep - deep lacustrine facies were developed.In the study area, from the margin to the center, the facies changed from delta plain, gradually to delta front, shore-shallow lacustrine and semi-deep - deep lacustrine facies, from bottom to top, the facies gradually changed from semi-deep- deep lacustrine to shore-shallow lacustrine facies, delta front, delta plain facies. The evolution process of the Qingshankou Formation can be divided into three stages based on the distribution character, including the early, middle and late stages. The sedimentary characteristics are different in different stages and different tectonic units. While, as a whole, the lacustrine basin is characterized by changing from large scale to small scale from the early stage to late stage.