Oil & Gas Geology ›› 2013, Vol. 34 ›› Issue (2): 185-191.doi: 10.11743/ogg20130207

Previous Articles     Next Articles

Reservoir characteristics and its main controlling factors of the Pinghu Formation in Pinghu structural belt,Xihu Depression

Hu Mingyi1,2, Shen Jiao1,2, Hu Die1   

  1. 1. College of Geosciences, Yangtze University, Wuhan, Hubei 430100, China;
    2. Key Laboratory of Exploration Technologies for Oil and Gas Resources, Yangtze University, Wuhan, Hubei 430100, China
  • Received:2012-08-13 Revised:2013-02-21 Online:2013-04-28 Published:2013-05-02

Abstract:

Based on comprehensive analysis of various data such as core observation,casting thin sections,scanning electron microscope,physical property analysis,mercury penetration and production test,we studied the characteristics and the main controlling factors of the sandstone reservoirs in the Pinghu Formation of Pinghu tectonic belt in Xihu depression.The results show that the reservoir rocks are dominated by feldspathic quartz sandstone with good sorting and roundness,moderate compositional maturity and high texture maturity.The reservoir is characterized by low porosity and low permeability or moderate porosity and moderate permeability,as well as a good correlation between porosity and permeability.The pores are dominated by intergmular dissolution pores and relic primary intergmular pores,the pore throats are mainly of necking throat,laminated throat and curved lamellar throat,and the pore-throat assemblages are dominated by moderate pore-coarse throat.The main controlling factors of reservoir development in the research region were studied in respects of sedimentary facies,diagenesis and abnormal high pressure.Sedimentary facies is one of the main factors controlling the reservoir quality.The sandstone reservoirs of delta plain distributary channel facies are the best in physical properties,followed by delta front underwater distributary channel facies.Compaction and cementation are destructive to reservoir physical property,while dissolution is constructive to reservoir physical property as it can generate secondary porosity.The existence of abnormal high pressure is also constructive to reservoir physical property,for it is helpful to the preservation of the original intergranular pores and to the improvement of dissolution of the early carbonate cement,resulting in intergranular dissolution pores and improving the reservoir physical properties.

Key words: abnormal high pressure, sedimentary facies, diagenesis, reservoir characteristics, Pinghu Formation, Pinghu tectonic belt, Xihu Depreesion

CLC Number: