Log Evaluation for Low Permeability Reservoir in Majing-Shifang Area

On the basis of analyzing the basic geologic characters of reservoir,conventional logging data,drilling data,mud logging data and test data are used to study the lithology identification method,reservoir identification method,reservoir fluid property identification and reservoir evaluation standard.A reservoir gas-baering judgement technique is developed which includes irreducible water saturation method,porosity log overlay method,volume compressibility and poisson ratio intersection method.The reservoir could be divided into 3 types① one is characterized by low gamma ray,high porosity and high resistance,② one is characterized by high gamma ray and(3) the other is characterized by low resistance.On the basis of reservoir classification evaluation,reservoir evaluation criteria are established.