The Tight Reservoir Characteristics And Formation Mechanism Of Periman Tiaohu Formation In Malang Sag,Santanghu Basin

To guide tight oil and gas exploration in Malang sag,Santanghu basin,we carry out the work in Permian tight reservoir research and evaluation.This paper make full use of the core,seismic and well logging data,rock slice,whole rock X-ray diffraction,and the experimental data of the whole rock X-ray diffraction,thin section authentication and scanning electron microscope experiment,combined with the geological background,we study tight reservoir petrology characteristics,diagenesis,reservoir space and the formation mechanism of Periman Tiaohu Formation in Malang sag,Santanghu basin.Research shows that:the tight reservoir of Periman developes lithology with volcanic lava and volcanic clastic rock,sedimentary rocks and diamictite.Reservoir space mainly include matrix pores,vitrified hole,dissolution pores and cracks.Tuff bore diameter in 0.01?m-1?m,good pore connectivity,porosity distribution in 3.07%-27.13%,average 16.97%,the average permeability are low,generally less than 0.5×10^-3?m²,uniform distribution.The tight reservoir diagenesis have the volatile,the condensation and contractionin,the vitrified,the filling,the compaction,the weathering leaching,the cementation,the metasomatism and dissolution.Article according to the diagenetic stages and diagenetic environment,reservoir group is divided into syngenetic stage?condensation period,hydrothermal period?,weathering leaching stage and burial stage?early and late?.Sedimentary environment determines the reservoir lithology density,the higher the clay mineral content of reservoir physical properties,the higher the content of chlorite,the lower Iraq/slip layer content in tuff,the better oil content,volcanic eruption control the formation of the primary pore seam,dissolution and vitrified effect is the key of secondary pore formation,tectonic movement control the development of crack.