关键词: 扫描电镜, 压汞试验, 微观溶蚀作用, 温度, 动水压力

Abstract:

Qualitative analysis of microcosmic mechanism of limestone dissolution driven by different temperatures and hydrodynamic pressure in CO2-H2O solutions are scanned by the environmental scanning electron microscope (SEM) before and after the mercury injection test. First, the limestone dissolution is influenced by temperature and water pressure besides lithology and structure, dissolution of micrite small than oolitic limestone under the same conditions. Secondly, the sample produced different magnitude irregular figure crystal under high hydrodynamic pressure, the increase and extension of pores and fissures. And that produced great magnitude regular figure crystal by rising temperature that the dissolution and deposition are increased. The dissolution not only affects on the surface of the rock produce secondary pore and secondary mineral, but also influences the inner pore structure; the pore structure became inhomogeneous and discontinuous, decreases the permeability and connection among the structural planes of rocks. These microscopic characters are also well documented the information and results of the dissolution process.

Key words: SEM, mercury injection test, microcorrosion, temperature, hydrodynamic pressure