摘要
松辽盆地梨树断陷营城组是一套以碎屑岩沉积为主的地层,其主要岩性为正常碎屑沉积岩,火山碎屑沉积岩居次。砂岩在所有岩性中所占比重最大,主要为长石岩屑砂岩和岩屑长石砂岩。砂岩的成分特征与酸性火成岩一致,反映火山岩物源的特点。营城组可以分为4个砂组,充填序列显示营城组主要由两个大的旋回组成:①营Ⅱ砂组和营Ⅰ砂组;②营Ⅳ砂组和营Ⅲ砂组。营Ⅱ末期和营Ⅳ末期分别为这两个大的旋回的最大湖泛面,识别出的沉积微相有14种类型,包括静水泥质沉积、浊流沉积、临滨砂坝、浊积水道、泥石流、辫状河道、片流沉积、分流间湾、河口坝、重力河口坝、水下河道、重力水下河道、远砂坝和席状砂。扇三角洲的重力河口坝和重力水下河道以及水下扇的浊积水道较为发育,是构造活动背景下沉积和再搬运的产物。这3种类型的砂体也是十屋油田重要的油气储层。
Yingcheng Formation Lishu faulted depression in Songliao Basin is a set of detrital rocks,in which the main lithological characters are normal detrital of with inferior pyroclastic sedimentary in rocks.The sandstone is the highest in proportion,including feldspar-debris and debris-feldspar sandstone.The composition characteristics of the sandstone are as the same as acidic volcanics,indicating the acid volcanic rocks in source characteristics.The Yingcheng Formation can be divided into four sand groups and two big cycles by filling sequence： ① Y2 and Y1,and ② Y4 and Y3.The ends of Y2 and Y4 are showing the maximum flooding surfaces of the two cycles.Fourteen sedimentary microfacies were identified,including mudstone of still water,turbidity sediment,nearshore bar,turbidity channel,debris flow,braided channel,laminar flow sediment,interdistributary bay,mouth bar,gravity mouth bar,underwater channel,gravity underwater channel,distal-bar and sheet sand.Among them,the gravity mouth bar and gravity underwater channel of fan delta,and turbidity channel of subaqueous fan,were developed well and the products of deposition and re-transportation in active setting.The three kinds of sand bodies are also important oil reservoirs in the Shiwu oilfield.
出处
《世界地质》
CAS
CSCD
2012年第1期28-39,共12页
World Geology
基金
国家自然科学基金(40972074)
关键词
松辽盆地
梨树断陷
营城组
岩石类型
岩性序列
沉积微相
Songliao Basin
Lishu faulted depression
Yingcheng Formation
rock type
lithological sequence
sedimentary microfacie
