The Well Logging Evaluation Technique Of Intermediate-basic Volcanic Rocks Of Yingcheng Group In Xushen Gas Field

In view of complex lithology, diversified fluid type, complex relationship of gan and water in neutral and basic volcanic rock, we are based on the reservoir of"four quality relationship"and directed by well logging theory, use the associated method of core scale logging, particular well logging and traditional well logging, establish one suit of comprehensive evaluation technology which includes reservoir lithology identification, fluid property recognition,parameter calculation and reservoir logging classification. We use ECS well logging to identify interim lithology and volcanic rock interbedding which is difficult to identify by using traditional method. We develop fluid recognition method including double density overlapping,transverse and longitudinal wave time difference ratio and nuclear magnetic logging. On the basis of studying the effect of especial mineral and alteration action on the resistivity, we distinguish synthetically the fluid property of neutral and basic volcanic rock. In view of the variable distinguishing feature of rock skeleton,we use variable matrix density method to establish interpretation model of effective porosity. On the basis of studying classification of similar porosity and permeability,we establish permeability computation module according to different category. After researching minimal effective pore throat radius and conductive path,we establish saturation interpretation model which is based on mercury penetration data and conductive aperture. Using above partial outcome,we establish reservoir logging clascification criteria which provide technical support for selecting straturm to attempt gas and deliverability analysis. The research outcome of this item has been used in reserve submission and well logging comprehensive evaluation in individual well. This method provides technical support for gas exploratory development.