鄂尔多斯盆地南庄地区长6油层组沉积微相研究

Sedimentary Microfacies of the Chang 6 Oil-bearing Formation in Nanzhuang District,Ordos Basin

通过测井、录井、露头以及岩心等资料,结合延长组区域上的沉积特征和沉积相演化规律,认为研究区长6油层组为湖泊-三角洲沉积环境,岩性主要为灰绿色泥岩、泥质粉砂岩与灰绿、灰白色长石砂岩互层;发育水下分流河道、分流间湾、河口坝、席状砂和浊流相等沉积微相;三角洲前缘亚相中的水下分流河道微相砂体连通性好,构成研究区内最主要的含油层系。通过对沉积微相的研究,为研究区低渗透油田的高效开发奠定地质基础,进而为下一步勘探部署工作做好技术支撑。

Used data of geochemical logging, well logging, outcrop, core and so on, combined with sedimentary characteristic and evolvement of sedimentary facies about YanChang formation in area. It is concluded that in studying district the sedimeritary environment of chang 6 oil- bearing formation are lake and delta; the lithologic are the alternation of celadon mudstone, muddy siltstone and celadon, hoar granule arcose, and the sedimentary microfacies include subaqueous distributary channel, interdistributary embayment, mouth bar, sheet sand and urbidity. The sandbody of subaqueous distributary channel in delta front has the fine connectedness and is the main reservoir in this area. By analyzing sedimentary microfacies, it lays a foundation for efficienty exploring the oilfield of low permeability and makes a technical guidance for next work.