An experimental study on simulation of stress sensitivity to production of volcanic gas from its reservoir

摘要

This paper provides important findings of research work that was undertaken on stress sensitivity of gas reservoirs which arises from decrease in pressure during production process. Junggar basin of China was selected as study area for the work undertaken. The basin has a typical fractured reservoir of which the stress sensitivity has been unclear for a long period. In order to study the stress sensitivity during production process, experimental methods for measuring stress sensitivity which simulates the depletive recovery process as well as permeability for the cores dealt with were designed. The experiments were carried out on 31 volcanic rock samples taken from 6 wells in the area of study. Stress sensitivity for results obtained during the depletive recovery for cores from un-fractured volcanic reservoirs was found to relatively weaker while stress sensitivity for cores obtained from fractured volcanic reservoirs was stronger. Terzaghi (1943) concept on effective stress and Li (1999) theory for body effective stress were adopted in this study.