牛庄洼陷沙三中亚段浊积砂体储集特征研究

根据岩心观察以及对油井资料、构造背景等资料的综合分析，认为东营凹陷牛庄洼陷沙三中亚段存在深水浊积扇和三角洲前缘滑塌浊积扇砂体。讨论浊积砂体的储集空间类型及各微相砂体的孔渗特征，认为主要发育剩余原生粒间孔隙、次生孔隙、原生微孔隙、微裂缝4种类型储集空间；内扇主水道和中扇辫状不道砂体的储集较好，而中扇辫状水道前缘砂体和外扇内的砂体粒度较细，杂基含量较高，原生孔隙小而少，因而其储集性能相对较差；成岩作用对浊积砂体物性的改造明显，压实、胶结及黏土填隙作用导致孔渗性变差，而溶蚀作用、交代作用则有利于孔渗性的改变。评价认为，沙三中亚段储集层为中低孔低渗型的中等储集层，这是沉积－成岩演化中埋藏深、形成时代早、成岩作用较强等因素造成的。

A study on reservoir characteristics of the turbidite sand body Shasan intermediate member in Niuzhuang sag in Dongying depression

In this paper, by examining cores of the Shasan intermediate section (E 2s 3 2) of the Niu30 and Niu43 wells in Niuzhuang sag and comprehensively researching their log data, tectonic setting and pore space feature, the authors of the paper think that there are two kinds of turbidite fan-the deep-water turbidite fan and delta front fluxoturbidite. Based on the above study and analysis, authors study in full their reservoir characteristics in respective microfacies type, sedimentation feature, pore genesis and controlling factor. There are four kinds of pore, such as: primary pore, secondary pore, micropore and micro-fissure. Sandbodies of inner fan main channel and middle fan braided stream are better reservoir rocks. Sandbodies of middle fan braided stream front and outer fan are worse reservoir rocks, because their grain size is smaller, mixture content is higher, primary pore is smaller. Compaction, consolidation, dissolution and recrystallization reformed obviously reservoir feature of the turbidities. Of which, compaction, consolidation and clay filling caused porosity and permeability descending, throat chocking, compaction, agglutination and metasomatism improved the reservoir feature. It is concluded that sand body of the Shasan intermediate section belongs to medium reservoir rock, which is characterized by middle to low porosity and low permeability. It is caused by deep burial, early formation times and strong diagenesis in the process of deposition to diagenism evolution.