埕宁隆起北坡新近纪沉积特征及发育模式

Sedimentary facies types and models for the Neogene deposits on the northern slope of the Chengning uplift

摘要: 综合运用岩心观察、薄片鉴定、测井、地震等分析方法和手段,对埕宁隆起北坡新近系馆陶组-明化镇组沉积相进行了系统研究。结果表明,研究区新近纪馆陶组-明化镇组发育辫状河和曲流河沉积,主要沉积微相有河床滞留、心滩、边滩、天然堤、决口扇及泛滥平原等。在相分析的基础上,进一步研究了区内沉积微相的平面展布特征及其演化规律,认为区内馆陶期为辫状河,明化镇组演化为曲流河。在此基础上,建立了埕宁隆起北坡新近系馆陶期-明化镇期的沉积模式,并探讨了不同模式下储集砂体的分布规律。

Abstract: The detailed examination of the sedimentary facies on the basis of cores,thin sections,well logs and seismic data have revealed that the Neogene Guantao Formation and Minghuazhen Formation on the northern slope of the Chengning uplift are composed of braided and meandering stream deposits,respectively.These deposits consist of the following sedimentary microfacies: riverbed lag,channel bar,point bar,natural levee,crevasse splay and flood plain microfacies.The Guantaoan and Minghuazhenian sedimentary models are proposed on the basis of the planar distribution and evolution of the sedimentary microfacies for the purpose of the exploration of the reservoir sandstones.