DISCUSSION OF THE PERMEABILITY INCREASING MECHANISM OF THERMAL TREATED ROCK

An experimental study of high-temperature treatment was carried out on a lot of rock samples,which come from reservoir formation,to determine the effect of thermal treatment on permeability and porosity,which were measured under the atmospheric pressure and room temperature.Results indicated that the changes of permeability and porosity exist a threshold temperature and they increased with increasing temperature in the rang of 100℃ to 800℃.Up to 800℃,permeability increased two orders and porosity increased ten times.According to these experiment results,the permeability increasing mechanism of thermal treated rock was discussed and analyzed in this paper from the theories of pore structure characteristic、mineral dehydration and destruction、thermal stress concentration、chemical bond breakage、stress relaxation and so on.