基于地震属性的冲积扇沉积微相研究

Analysis of Alluvial Fan Sedimentary Microfacies Based on Seismic Attributes

利用地震资料将沉积与地震属性相结合,是目前针对钻井资料较少的区域,开展沉积相研究最有效的方法。研究区主要以冲积扇砂砾岩沉积为主,地震反射杂乱,利用常规砂泥岩储层沉积相分析方法较难准确识别各沉积相带特征。通过岩心特征、测录井资料等地质分析,结合地震属性解释结果,确定了目的层沉积特征及演化规律:五3东区上乌尔禾组属于冲积扇沉积体系,物源来自西北方向,主要发育扇根、扇中亚相,有利微相以粗粒度、强振幅的主河道、主槽、辫流线为主。

It is the most effective method to carry out the research of sedimentary microfacies by using thetechnic of seismic attribution analysis with the principle of sedimentology in the study area with lessdrilling data.The mainly deposition in Wusandong area,located in the northwestern margin of JunggarBasin,is glutenite from alluvial fan.Because of the desultory interior reflections,it is difficult toaccurately identify the facies characteristics by using conventional sedimentary facies analysis method ofsand mudstone reservoir.Based on the data of cores,mud-logging,assay and logging data,the authorconfirmed sedimentary characteristics and evolution law of Upper Wuerhe Formation in this area.Theresults showed that alluvial facies was the main sediment type of this formation,including main channel,main trough,braided stream sand island,sheetflood,etc,whose provenance mainly from the northwest.