The influence of steam stimulation on compression coefficient of heavy oil reservoirs

The diminishing oil resources make the exploration and development of heavy oil reservoirs more and more important. Heavy oil reservoirs need steam stimulation or other thermal development methods; temperature increasing during the thermal recovery process will inevitably affect the reservoir compressive characteristics. In order to study the variation of the compression coefficient of heavy oil reservoirs in the multi-round steam stimulation process, the compression coefficients of the reservoirs after different temperature and pore pressure cycles were tested. The results show that the compression coefficient of heavy oil reservoir decreases with the increase in effective confining pressure and increases with the increase in test temperature; After the temperature and pore pressure cycle, the compression coefficient of the rock is greatly reduced; the decrease in range of compression coefficient of the reservoir after the temperature and pore pressure cycle increases with the increase in the test temperature, and increases with the increase in maximum effective confining pressure. The dynamic variation of the reservoir compression coefficient must be taken into account in the prediction of the production capacity of multi-round steam stimulation.