Reservoir Recognition And Evaluation Method Research Of Low Permeability Sandstone In Pugu 1 Area Of Nanpu Depression

With the exploitation of oil and gas exploration and development,the evaluation of unconventional reservoir identification becomes more and more important.The low permeability sandstone reservoirs in Nanpu Depression generally have complex pore structure,complex rock-electricity relationship and complex logging response characteristics.It is difficult to interpret and evaluate this kind of reservoir by traditional logging evaluation methods.Based on a large number of experimental data of petrophysics and logging data,the petrophysical characteristics of low permeability sandstone reservoirs in Nanpu Depression are analyzed in this paper.The lithology is mainly fine sandstone,the pores are semi-connected and compact pore structure,and the rock-electricity relationship has non-Archie phenomena.In view of these characteristics,the lithology function method is used to model reservoir lithology,and the interpretation model of reservoir parameters such as porosity,permeability and saturation is established by using the method of reservoir quality classification and deep learning based on large data.On this basis,the reservoir quality factor RQI and the reservoir of NMR pore component expressed by logging data are obtained respectively by using conventional logging data.The characterization method of formation validity and the classification and evaluation criteria of reservoir validity characterized by mercury injection experimental parameters.The oil-bearing property of reservoir is identified and evaluated by means of various cross-plots.The above methods have achieved good application results in the study area and played a positive role in identifying and evaluating other similar reservoirs in the area.