基准面变化对分流河道沉积特征的影响——以鄂尔多斯盆地南部石盒子组为例  

Study of sedimentary characteristics of deltaic distributary channels controlled by base level change:A case from Shihezi formation of south of Ordos basin

作　　者：苏东旭[1] 于兴河[1] 李胜利[1] 单新[1] 周进松 韩小琴 苗亚男[1] 王娇[1] 

机构地区：[1]中国地质大学(北京)能源学院,北京100083 [2]陕西延长石油(集团)有限责任公司研究院,陕西西安710075

出　　处：《东北石油大学学报》2015年第1期59-68,4-5,共10页Journal of Northeast Petroleum University

基　　金：国家自然科学基金项目(41272132)

摘　　要：综合利用测井、岩心、薄片及野外露头等资料,分析鄂尔多斯盆地南部石盒子组分流河道砂体结构、沉积构造、岩相组合、砂地比、测井响应、河道垂向叠置样式和平面形态等特征,以及石盒子组基准面变化与三角洲分流河道沉积的响应关系.结果表明:基准面处于低位阶段时,砂岩粒度最粗,分流河道广泛发育,以辫状河型为主,弯曲度较小;随着基准面逐渐上升,分流河道数量减少,以曲流河型为主,弯曲度逐渐增大;基准面处于高位阶段时,分流河道数量逐渐增加,以网状河型为主,弯曲度最大.随基准面变化,三角洲分流河道具有辫状河型—曲流河型—网状河型的演化特征,建立分流河道沉积演化模式.该研究为研究区下一步勘探和开发提供依据.Based on logging,cores,microscope data and outcrop data,this paper takes the Shihezi formation of south Ordos basin as an example to analyze the grain size,structure,lithofacies,sand ratio logging pattern and stacking pattern in cross and in plane,and then to discuss how the distributary responds to baselevel change.Results show that when the baselevel at low stage,the grain size of sand is the most coarse and there are a lot of distributary,which shows the character of braided river with low sinuosity.As the baselevel rises,the amount of distributary decreases,and shows the character of meandering river identified by high sinuosity.When baselevel is at the high stage,there are more and more distributary with high sinuosity,which shows the character of anastomosing river.With the change of baselevel,the distributary tends to show the regular of braided to meandering than to anastomosing,based on which we construct the evolution model.

关 键 词：基准面变化 分流河道 曲流河 辫状河 网状河 沉积特征 鄂尔多斯盆地 石盒子组 

分 类 号：TE122.23[石油与天然气工程—油气勘探]