关键词: 辽河凹陷, 沙河街组, 砾岩油气藏, 沉积微相, 岩相, 测井解释

Abstract: The Shahejie Group in the Lengdong-Leijia region in Liaohedepression is mainly composed of very thick conglomerates,It belongs to a fan-delta sedime ntary system.Since thereservoir is close to the sources formation,the sorting is bad and its mudy interlayers are notwell developed.So microfacies can not be subdivided by use of single index such as sand-mudratio SP,NGS logging curves and other traditional methods. Based on the single-well faciesanalysis in a system-cored well,a lithologic model was established by using sonic-density-netron cross plots.In accordance with the above model,nonglomerate lithofacies were studied.By synthesizing the results of single-well-facies anlysis and lithofacies,with a combination of sedimentary environment and lithofacies,a study of sedimentary microfacies was carried out.Also,the relation between various sedimentary microfacies,physical properties andoilgas abundance are studied,which provided a reliable geologic basis for the prediction ofareas with good reservoir zone,a study of reservoir heterogeneity and a comprehensive evaluation of the reservoir.Meanwhile,this paper explores a new approach to study the conglom-erate sedimentary microfacies,which is also useful in other areas.

Key words: Liaohe sag, Shahejie group, hydrocarbon reservoir of conglomerate, sendi-mentation microfacies, facies, logging interpretatior