Well Logging Evaluation Of The Low Porosity And Low Permeability Reservoir In Wuliyasitai Sag

with the continuous improvement of the oil and gas exploration and development, low porosity and low permeability reservoirs of proved reserves also increased year by year, type of reservoir has become the focus of current and future exploration and development, and become the important object of the logging research a. However, because of its complex geological origin and formation conditions, leading to its evaluation of identification more difficult. Huabei Oilfield prevalence of low porosity and low permeability reservoirs, Huabei Oilfield stable output as the main task, a correct understanding of the evaluation of low porosity and low permeability reservoirs has become the primary goal of the Huabei Oilfield.Wuliyastai sag is located in the the Inner Mongolia Autonomous Region Xilinguole Mengdo Wuzhumuqin Mu Qinqi structure, belonging to the northeast end of the Manite Depression of the erlian basin. It present North East long Strip type,in the middle of Bainbaoolige and Sunite Uplift, oil and gas exploration began in1987, The first drilled taishen1well,there is good oil and gas shows in the lower part of teng1, After fracturing daily Oil production reached5.84t, To achieve the industrial oil flow, the main exploration target for the Lower Cretaceous, the major oil layer for Teng, Sec, Teng, section A, Sec and Asan segment.According to conventional logging data, rock physics experiments to analyze the data and the outcome of the test oil, the reservoir "sexual" relationship between porosity, permeability, influencing factors were analyzed. Recognize the impact of low porosity and permeability reservoir evaluation factors, mainly the following points:①complex lithology, including sandstone, conglomerate, muddy sandy conglomerate, tuff, etc.;②The complex pore structure, the types of pores are convex pore structure of the bimodal pore structure and a single peak, but other types of pore structure content can not be ignored; high③arbonate content and high mud content, relatively large impact on permeability.Rock physics experiments, combined with logging data, geological data, computer technology and mathematical methods, carried out the evaluation method of low porosity and permeability reservoir logging, according to research results, the preparation of the handler, the application to the destination block to deal with seven well logging data, the following conclusions:(1) the impact of reservoir porosity, permeability are three main reasons:First, the lithology of the region is complex, including fine-grained sandstone, conglomerate, muddy sandy conglomerate, tuffaceous sandstone, tuff, poor sorting of particles small particulate debris filling the pores between the large particles and roared, and reduces the porosity and permeability of the rock; cement content of tuffaceous, resulting in rock storage capacity and infiltration capacity variation; pore complex structure, various types of pores are mainly convex pore structure of the bimodal pore structure and a single peak, but the pore structure of other types of content can not be ignored. (2) The reservoir properties of the block Stengel group is mainly affected by the clay content, Arxan tuffaceous content, so consider the influencing factors on the basis of reservoir porosity, permeability calculation model proven, reliable calculation parameters.(3) core experimental data and logging response characteristics, select the acoustic time is closely related to the lithology, neutron, density, natural gamma ray and resistivity curves cross plot. Cross plot of the variation, the establishment of lithology identification standard.(4) technical route to the core scale logging, core analysis closely integrated data and logging data based on study of reservoir characteristics and to determine accurate reservoir parameters and interpretation of model, and ultimately to the establishment of oil and gas interpretation chart and standards.