Effectiveness Evaluation Of Volcanic Reservoir In Wu Lanhua Sag Of Erlian Basin

With deepening of petroleum exploration and development,more and more volcanic rock reservoirs are attracted by people's attention.Wulanhua sag in Erlian Basin is a new exploration and development block of Huabei Oilfield in the recent years,industrial oil flow has been found in the volcanic rock reservoir in Wulanhua Sag.As the basis for the evaluation of recoverable reserves,it is critical to evaluate the effectiveness of volcanic rock reservoirs with logs,which is a key link in the design of subsequent development plans.In the thesis,core data and logging data were combined with oil test data for volcanic reservoir logging evaluation,and the results show that reservoir lithology is mainly including granite and andesite.Granite reservoir space are dominated by fractures which their development is controlled by faults.Andesite reservoir space are mainly micropores and amygdala pores,the reservoir performance is greatly affected by dissolution.Micro-resistivity imaging logging combined with core and the conventional logging data is mainly used to evaluate fractures of granite reservoirs,and granite reservoirs are divided into three categories according to logging response and oil test results.In view of the characteristics of the development of micropores and amygdala pores in andesite reservoir,nuclear magnetic resonance logging was used to evaluate porosity,and the effective porosity of andesite reservoir was calculated,according to the logging response and oil test results,they are divided into three categories.The effective reservoirs of volcanic rock reservoirs in Wulanhua Sag could be identified with quantifying the classification results into tables.The logging evaluation results show that the volcanic rocks in Wulanhua Sag can form effective oil and gas reservoirs with small porosity and low permeability,subsequent development of some reservoirs requires fracturing.