Characteristics And Distribution Of Volcanic Reservoirs In Pingbei Area,Xihu Sag,East China Sea

The exploration and development of oil and gas has made great progress in Xihu sags,the East China Sea shelf basin.The exploration of Volcanic rock in this area has also attracted more and more attention.Although the volcanic rock reservoirs in this area have exploration potential,there are many difficult in exploration,such as less data,diverse rock types,and complex diagenesis.new data of the basis of previous research in this area.Based on thin section,logging data,and chemical analysis tests,This paper study on volcanic reservoirs in the Pingbei Area of the Xihu Sag,including analysis of reservoir types,reservoir properties,diagenesis,main control factors,and distribution patterns.The volcanic reservoir space developed in the north of Xihu Sag.It can be divided into three types and eight species.The main reservoir space types in the study area are structural fractures and dissolution pores.In the study of volcanic reservoir properties,it is found that the tuff reservoir has the best physical properties,high porosity and permeability,and that of dacite lava.The physical properties of the clastic sedimentary subfacies with the external clastic are the best and the thermal detrital subfacies are the second.The diagenesis of volcanic rocks in the Pingbei area of the Xihu sag can be divided into protogenetic and subgeogenic.It can be further subdivided into seven types.Dissolution and tectonization are the most frequently occurring diagenesis in the Pingbei area of Xihu Sag.Pyroclastic rock porosity decreases with buried depth.Volcanic clastic rock in Pingbei area of Xihu Sag is common.The upper part of the reservoir is well developed due to weathering and leaching,and gradually weakens as the depth increases.In areas where tectonic development takes place,its dissolution is enhanced and the development of the reservoir becomes significantly better.