Research Of Logging Evaluation For Beach-bar Sand Reservoir In Shengli-B Area

In the current beach bar sandstone reservoir logging evaluation,the following problems are faced: First,the reservoir is thinner,siltstone,argillaceous siltstone,calcareous siltstone and shale interact with each other,and the physical heterogeneity is large.The vertical resolution of the instrument is low,the logging curve is affected by the surrounding rock,it is difficult to represent the true response of the formation,the reservoir effectiveness evaluation ability is limited;the second is the lithology is complex,the reservoir porosity,permeability are low,the salinity of formation water changes greatly,resulting in reservoir physical properties and oil saturation calculation accuracy is low.In this paper,for the difficult evaluation of the beach bar sand logging,the pioneering work is carried out to form a set of logging evaluation method suitable for the beach bar sand reservoir.Based on the experimental study of petrophysical physics and datas of testing for oil,by means of key wells research,using core and imaging,nuclear and other special logging,combined with geological,method of test data scale conventional log data,research the structure,sedimentation,pressure,productivity and stratigraphic water salinity and resistivity plane distribution characteristics of the beach sand reservoir.In view of the beach sand dam thin interceding lithological combination mode,we study the Walsh inversion method,the longitudinal response discrete method,the resolution matching method and the Fourier spectrum method to improve the longitudinal resolution of the logging curve,optimize and determine the suitability of each method.Based on the core experimental data,the intrinsic relationship between the reservoir parameters is analyzed,a three-level parametric model of macro scale,micro-scale and seepage is described,Sub-regional,hierarchical system to establish a variety of fine calculation model,which can effectively improve the accuracy of reservoir parameters such as mud content,gray matter content,porosity,permeability,water saturation and irreducible water saturation.The lower limit of reservoir effectiveness is given by lithology,physical property,oil-bearing property,electrical and liquid-lower limit.Based on the comprehensive indication curve of reservoir quality constructed by three kinds of parameters,the establishment of different regions can be obtained natural capacity layer,the need for reservoir transformation to obtain capacity layer and dry layer of the criteria.