Research on Triassic Chang 6~1 reservoir in Weijialou area of Hengshan oilfield

In the Hengshan oilfield Weijialou area Chang 61 oil layer, the reservoir petrology, physical properties, pore structure and reservoir controlling factors is studied. The layer of reservoir rock type is mainly fine-grained feldspar sandstone and lithic arkose, low compositional maturity, high textural maturity; overall petrophysical property is poorer. It is characterized by low porosity, low permeability reservoir with development of intergranular pores, intergranular dissolved pore, intragranular dissolved pore, mould pore, intergranular micropore and the micro crack pores, among which it is mainly secondary intergranular dissolution pores. In the throat channel, it mainly developed fine throat - micro laryngeal. After sedimentation occurs, the diagenesis controlled reservoir pore structure and reservoir physical property. Based on the lithology and physical property, the reservoirs are divided into 3 categories:Class Ⅰ is good reservoir, class Ⅱ for better reservoir, and Class Ⅲ poor reservoir.