摘要
利用地震、测井以及钻录井资料,对溱潼凹陷俞跺—华庄地区开展了沉积微相研究。该区阜三段沉积微相主要有水下分流河道、分流间湾、河口砂坝、远砂坝、前缘席状砂、前三角洲泥等6种微相;表现为2个反旋回沉积特征,即Ⅳ油组到Ⅲ油组、Ⅱ油组到Ⅰ油组均为从水深到水浅的变化,为三角洲发育的2个进积过程;自下而上表现为前三角洲亚相(前三角洲泥)—三角洲前缘亚相(前缘席状砂、河口坝、分流间湾、水下分流河道),为2个自下而上由细变粗的反旋回特征。宏观上三角洲前缘亚相与前三角洲亚相相互叠置。由于受基准面升降及入湖河道摆动的影响,不同期次三角洲前缘进积砂体发育程度及分布范围不同,宏观上为多期砂体加积,微观上则是沉积相序的改变。明确了俞垛—华庄地区阜三段沉积微相的空间展布规律,对该区阜三段下一步的勘探开发具有指导意义。
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.
出处
《石油实验地质》
CAS
CSCD
北大核心
2014年第1期51-55,共5页
Petroleum Geology & Experiment
关键词
沉积微相
阜宁组
古近系
溱潼凹陷
苏北盆地
sedimentary microfacies
Funing Formation
Paleogene
Qintong Sag
Northern Jiangsu Basin
