Dissolution of Carbonate Rocks in CO2Solution under  the Different Temperatures

Key words: 
• carbonate rocks /
• dissolution /
• Sichuan basin /
• Feixianguan formation /
• simulating experiment

Abstract: It is thought generally that dissolution of acidic fluids is an important controlling factor for forming carbonate reservoir. This study focuses on the ability of dissolution of different type carbonate rocks in CO2 solution using a new simulating experiment way. The results show that the ability of dissolution of different carbonate rocks changes from low to high and again to lower with the simulating temperature from 25℃ to 200℃,and the maximum ability of dissolution is at 60～90℃; the ability of dissolution of dolomite is lower compared with the ability of dissolution of calcite, and the ability of dissolution of transitional type carbonate rocks is between calcite’s and dolomite’s, and the ability of dissolution is very lower and their different is very small for all type carbonate rocks in CO2 solution when the simulating temperature is higher than 150℃.This indicates that CO2 solution has important effect on dissolution of limestone and less effect on dissolution of dolomite during late stage of early diagenetic to early stage of middle diagenetic and the forming of good dolomite reservoir is related to dolomitization.