渤海湾盆地大民屯凹陷沈84-安12区块沙河街组三段储层特征及主控因素OA

The third member of Shahejie Formation(Es3 Member)in Shen84-An12 block of Damintun sag are key target srata series for oil and gas exploration in Bohai Bay Basin.In view of the problem of less understanding on main controlling factors of reservoir development and distribution of favorable reservoirs in current blocks,the pet-rological and physical properties of Es34Ⅰ,Es34Ⅱ and Es33Ⅲ reservoirs of Es3 Member of Shen84-An12 block are quantitatively studied by full use of coring well analysis,testing,drilling and logging data,and the main control-ling factors of reservoir development are analyzed to carry out favorable reservoir prediction.The results show that reservoir is mainly feldspathic lithic sandstone with relatively low maturity of composition and medium maturity of texture.Primary pores are the main reservoir space.Average porosity of reservoir is 22.1%,and average permeabili-ty is 412.8×10-3 μm2,making it a medium-porosity and medium-permeability reservoir,and the porosity-permeabili-ty correlation is poor.High-quality reservoirs mainly develop in high-energy facies belt of underwater distributary channels in fan-delta front.On the basis of facies control,compaction and cementation further affect the physical properties of the reservoir,causing a decrease in porosity and permeability.The application of waveform indication inversion can effectively predict the extention range of favorable reservoirs and provide a basis for well deployment of progressive exploration in mature oilfields.