鄂尔多斯盆地白河地区长4+5储层控制因素分析

延长油田股份有限公司 吴起采油厂,陕西 延安 716000

储层特征; 沉积作用; 成岩作用; 延长组; 白河地区

Control factors of Chang 4+5 reservoir characteristics in Baihe area,Ordos Basin
LI Jiang-shan,LIU Yu-bo

(wuqi Oil Production Plant,Yanchang Oilfield Co., Ltd.,Yan'an 716000,China)

reservoir characteristics; sedimentation; diagenesis; Yanchang Formation; Baihe area

DOI: 10.13800/j.cnki.xakjdxxb.2015.0315

备注

鄂尔多斯盆地白河地区延长组长4+5油层组是重要的储集层,包括长4+51和长4+52等2个小层,弄清该区的储层特征及其控制因素具有重要意义。对储层岩石学特征、孔隙特征、储层物性特征及储层影响因素进行分析,评价了储层的储集性能及非均质性。结果 表明,该区砂岩由浅灰色含油细粒长石砂岩、细-中粒长石砂岩和中粒长石砂岩组成; 储层孔隙类型以粒间孔、溶孔和微裂缝为主,储层整体上呈特低孔、特低渗储层特征。沉积作用和成岩作用是造成储层特低孔、特低渗的主要原因,沉积作用控制了砂体的展布; 成岩作用过程中压实与胶结作用使储层孔隙大量减少,溶蚀作用对孔隙建造具有积极作用。根据岩性和物性特征,该区储集岩呈现空间上的非均质性,且长4+52储集性能明显好于长4+51。

Reservoir of Chang 4+5 is composed of Chang 4+52 and Chang 4+51 sublayers,is an important oil reservoir in Baihe area in Ordos Basin.Make clear control factors and the reservoir characteristics have great significances.Based on petrological and physical features,study characteristics of Chang 4+5 oil reservoir set,evaluated reservoir properties and reservoir heterogeneity.Result shows that the reservoir sandstone is compose of light grey oily fine-grained arkose,fine-grain arkose and grain arkose; the pore types are mainly intergranular pores,dissolved pores and microfracture,indicates that Chang 4+5 oil reservoir belongs to low porosity,low permeability reservoir.Sedimentation and diagenesis are the main factors.Sedimentation controlled the distribution of reservoir.Compaction and cementation decreased the primary pores,dissolution has positive effects on pore construction.Based on lithology and physical properties,the reservoir is heterogeneity in the space,and the Chang 4+52 reservoir performance is significantly better than Chang 4+51.