In recent years

deep and ultra-deep carbonate reservoirs have shown great potential in petroleum exploration.However

prediction of high quality deep and ultra-deep carbonate reservoirs is constrained by understanding of the mechanism of carbonate dissolution/precipitation.The study on this process could provide insight into the pore development mechanism of petroleum reservoir space.In this study

we conducted dissolution-precipitation experiments simulating surface to deep burial environments.The effects of temperature

pressure

water-rock ratio and dissolved ions on the carbonate dissolution-precipitation process were investigated under conditions from normal temperature and pressure to high temperature and pressure (~200℃~70 MPa) with a series of petrographic and geochemical analytical methods.The results show that the dissolution window curve occurs between 75~150℃ in the open system

and 120~175℃ in the semi-open system.In the open system with 0.3% CO

2

solution

the dissolution capacity of calcite is significantly higher than that of dolomite

while in the semi-open system with 0.3% CO

2

solution

dolomitic limestone has the highest dissolution capacity.In the open system with diluted H

2

SO

4

solution

the dissolution capacity of dolostone surpasses that of limestone when the temperature is over 175℃ due to surface-complexation processes of sulfide and cation.