Research On Logging Interpretation Method Of Carboniferous Dolomite Reservoir In Bama Area

The carboniferous reservoir of the BaMai area is one of the key blocks of XiBeiJu branch exploration and development,But since exploration breakthrough in the block hasn't executed systematic research of logging interpretation method,the current interpretation method is the same as logging interpretation method of the carboniferous carbonate reservoir in TaHe area,but two areas of the BaMai and TaHe have a great different reservoir geological characteristics,especially qualitative evaluation of the pore space structure,lithology and physical properties of reservoir,as well as the relationship of oil,gas and water about the low resistance reservoir below background of high resistance,have a strong regional characteristics.This article,proceeded from the perspective of the characteristics of microscopic pore structure and macroscopic property,is writed by discussed around these questions,this has a certain significance for oil and gas exploration and development of the area.The paper,based on the core observation and experimental analysis,make the analysis and comparison for the microscopic pore space structure characteristic of carboniferous reservoir in BaMai area.Especially using litho-electric experiment parameters,relative permeability experimental analysis evaluate the connectivity of reservoir microscopic pore space,and evaluate the storage properties of reservoir for the carboniferous Xiaohaizi(C2x)group and Bachu group(C1b).Analysis results show that reservoir microscopic pore structure of C2x is superior to C1b.The lithology of Carbonate reservoir changes very frequently on the longitudinal,so the high precision reservoir recognition,the evaluation of lithology and physical properties have larger difficulties.In this paper,the miscibility scale analysis method is innovative used to qualitative identification of the lithology,reservoir and evaluation of the size of the reservoir apparent porosity,which based on three porosity log data make uniform porosity scale range for different lithology,then evaluate the focus degree of three porosity log curves.The method in the area obtain good applying effect.The identification of Carbonate reservoir fluid property is another problem for us,especially the reservoir major lithology in this area is dolomite,so the hydrogen index in rock matrix paremeter is uncertain,which makes more difficult for fluid property identification of low resistance reservoir below high resistance background.In this paper,the experimental results that high salinity formation water made anomalies of neutron porosity of dolomite,is used to identify the water layer,and the method has obtained the very good application effect.In addition,using the methods of P1/2 RT-POR,neural network identify integrally reservoir fluid types,and also effectively solve the problem of fluid properties in this area.