The proposing of Braid Delta of Yaojia Group, Baicheng Water System of the Western Sedimentary System in Southern Songliao Basin and Its geological Significance

摘要

The Western Sedimentary System in South Songliao Basin is one of the three Sedimentary System in Middle Part of Songliao Basin. TaoBao Viscous Oilfield in Western Slope which is controlled by the Western Sedimentary System has been developed. Lithology reservoir is controlled by single or multi―direction reservoir pitch ― out; stratigraphic reservoir is controlled by stratigraphic pitch ― out and reservoir lithology pitch ― out. Braid delta is the type between fan delta and regular delta. Separating braid delta from fan delta has important guiding influnce in fully understanding the facies zone of Baicheng Water system of Western Sedimentary System in South Songliao Basin, forecasting facies belt and reservoir type and distribution in no well and no seismic data area in Western Slope south Songliao Basin,finding large stratigraphic overlap trap in west of Taobao within 10 ― 32 miles.