Study On The Characteristics And Control Factors Analysis Of Oil&Gas Reservoir Of Chang81in The Zhenbei Oilfeild

This paper goes on to research and discuss the characteristics of petrology, microscopic reservoir characteristics, diagenesis and reservoir physical properties. In this process, this paper analyses this points by means of methods under the guidance of sedimentology, reservoir sedimentology and oil geology. The methods include the detailed description and observation of drilling cores, and observation of thin-section of the cast,measurement of homogeneous temperature for inclusions, analyses of X-ray diffraction,cathode luminescence image, electron scan microscope, capillary pressure and. After the comprehensive research of reservoir, the paper holds that:The componential and textural maturities of the sandstone in chang81formation of zhenbei Oilfeild is lower and lithological types are mostly fine feldspathic debris sandstore and rock fragment feldspathic sandstore. The type of cements obsedved including Ferroan Calcite, Chlorite and Illite. The paper thinks the form two functions are the main reasons of decreasing reservoir quality. The reservoir physical properties show that Chang81is determined to be the front-delta deposition of delta deposits. The average porosity is10.3%,11.1%,and the average permeability is1.0×10-3μm2å'Œ1.2×10-3μm2in the Chang811formation and Chang812formation. The reservoir is characterized by low porosity and lowpermeability. According to the characteristics of diagenesis the lithogenous phase is made. The authigenic clay rim (chlorite) and feldspar dissolution diagenetic phase is considered as advantage diagenetic phase.The paper holds that the high quality reservoir is controlled by provenance and parent rocks properties, diagenesis and the degree of diagenetic evolution.The fractures of reservoir on one hand make the pores connect, improve the reservoir quality of the sandstones.On the other hand,act as the role that transporting petroleum.