Delta Front Outcrop Architecture Analysis of Permian Shanxi Formation in Cheng Jiazhuang, Liulin, East Ordos Basin

Through detailed analysis of outcrop sections, based on lithology, sedimentary structures, colors and sedimentary environment, sand body architecture of delta front is researched in Cheng Jiazhuang district, east Ordos Basin of Permian Shanxi formation. Results show that there are ten kinds of lithofacies and seven sedimentary units in the study area. According to sedimentary cycle and lithofacies assemblage characteristics, six types of fourth level architectural units, i.e., distributary channel, distributary bar, tide sand-dam, estuarine dam, distal bar and sheet sands are identified. They also formed fifth level architectural units in delta front in a complicated assemblage style. Assemble patterns of architectural units are divided into vertical stacking type, lateral joining type and isolated type. Through field measurement, architectural units are quantitative characterized. Result show that there is a linear relationship with a high relativity between thickness and width of distributary channel, distributary bar, estuarine dam and distal bar, which can provide a geological basis for modeling of subsurface architectural units.