摘要
Abstract
The studies of sedimentary microfacies have been carried out in the Yuduo-Huazhuang area of the Qintong Sag based on seismic, drilling and logging analyses. 6 types of microfacies have been identified in the 3rd member of the Funing Formation in the study area, including underwater distributary channel, interdistribu-tary bay, channel mouth bar, distal bar, frontal sheet sand and prodelta mud. There are 2 reverse cycles, i. e. from oil group ⅣtoⅢand fromⅡtoⅠ, both evolving from deep water to shallow water, indicating for 2 pro-gradational processes of delta formation. From bottom to top, the prodelta mud microfacies (prodelta mud) changes to delta front microfacies ( frontal sheet sand, channel mouth bar, interdistributary bay and underwater distributary channel) , indicating for 2 reverse cycles which become coarse upwards. The delta front microfacies interbeds with the prodelta microfacies. Influenced by base level changes and stream entering lake, the generation degree and distribution range of delta front progradational sandbody of different stages are various, i.e. multiple stages of sandbody aggradate from macro view, and sedimentary facies sequences change from micro view. The distribution rules of sedimentary microfacies of the 3rd member of the Funing Formation in the Yuduo-Huazhuang area have been identified, which have guiding significances for further explorations.关键词
沉积微相/阜宁组/古近系/溱潼凹陷/苏北盆地Key words
sedimentary microfacies/Funing Formation/Paleogene/Qintong Sag/Northern Jiangsu Basin分类
能源科技
