Study Of Sedimentary Facies Characteristics Of Lower Porosity And Permeability Reservoir And Logging Interpretation Method

With the depth of oil exploration and development,various oil continuous improvement of technology, low porosity and low permeability sandstone reservoir exploration and development has become an important component. There are many different feature between the oil and gas reservoirs with low porosity and permeability and high porosity and permeability reservoir, so does the method of logging evaluation and division of oil and gas layer. It is significant to analysis of their sedimentary characteristics,its relationship with the sedimentation system and research logging evaluation methods of low porosity and low permeability reservoir.In this paper, through the integrated application of testing, geology, logging, information, etc. Starting from the study of the sedimentary characteristics, its relationships with the sedimentation system of low porosity and low permeability reservoir was studied, in the Bohai area BZ25-1 oilfield Shahejie formation. It is shown that sedimentation have impacted on the low porosity and low permeability reservoir, the sedimentary environment in research formation determining the characteristics of the reservoir in nature, in the macro control of the type of sand body, shape, thickness, size and distribution., affect the sand flat and vertical distribution and layer, layer heterogeneityc, determine the particle size of rock debris, the amount of interstitial material, rock structure characteristics, determine the original reservoir porosity and permeability whims of the good or bad.As the deposition conditions, the formation of sedimentary detritus of the composition, particle size, degree of sorting, cement type, pore filling, sand body morphology, lateral continuity and vertical connectivity, thickness varies, making the reservoir rock sexual, physical properties, microstructure, bedding structure in the vertical, horizontal, there are different degrees of difference. Low porosity and low permeability reservoirs in the study area are mainly developed in the mouth bar, distal bar of the fan delta front sandbodies and the sublacustrine fan sandbodiesApplication of mercury intrusion, scanning electron microscopy, cast thin section analysis and test tools, etc. The reservoir characteristics of micro-pore structure were carried out, it is shown that the pore structure of reservoir could be classified into four types, the type ofâ…¢,â…£pore structure are mainly exists in the low porosity and low permeability reservoirs. Pore structure of different types of reservoirs variation of its electrical parameters of rock, by using a variable m to value reservoir oil saturation could achieve better results; Established a study area for the interpretation of low porosity and low permeability reservoir model, including shale content model,porosity model,permeability model,irreducible water saturation model; Established a regional and charts for the identification of single well oil and water layers; The actual logging data processed results indicated that well logging explanation has been greatly improved.