不同温度条件下碳酸盐结晶沉淀研究

本文结合碳酸盐岩溶蚀机理研究,从理论上并通过模拟试验对与温度条件密切相关的碳酸盐结晶沉淀作用进行了探讨。在大量矿物结晶显微照片及测试数据的基础上,阐明了石炭岩、白云岩等碳酸盐岩类在不同温度条件下(25℃、40℃、60℃和80℃)溶蚀一结晶过程中碳酸盐晶体形态及生长发育的不同特征。同时还探讨了随溶蚀—结晶时间、压力及溶蚀液性质的改变,晶体形态、晶粒大小、结晶速率等的变化趋势。这项研究对反演自然界碳酸盐岩溶蚀—结晶过程和喀斯特形成发育规律、探索碳酸盐岩的成岩作用以及评价油气水等岩溶裂隙储集层特征等均具有重要意义。

STUDY ON THE CRwnLLIZATION AND PRECIPITA-TION OF CANBONATE AT DIFFERENTTEMPERATURE CONDITIONS

The crystallization and precipitation can be classified into many types. Many scientists both at home and at abroad have studied this problem in detail, and a great deal of valuable results have been obtained. But the greater part of the research has been put emphasis on its macroscopical cha-racters. The microscopical research is not commonly seen, especially, the relationship between crystal form and temperature of corrosion solution is rarely touched. In recent years, in the process of studying the mechanism of corrosion of carbonate rocks, we have probed into the crystallization and precipitation in close relationship with the temperature theoretically and through the simulated tests. On the basis of a vast amount of mineral crystal micrographs and measured data, this paper clarified the different characteristics of crystal form and cryctal growth In the process of corrosion-crystalliz-ation of limestones, dolomites and others at different temperature conditions (25℃, 40℃, 60℃ and 80℃) . From this it is concluture conditions (25℃ , 40℃ , 60℃ and 80℃) . From this it is concluded that with an increasement of the temperature within limits, not only the obvious changes of crystal form have been shown, but also a series of regularity of crystal grain sizes from small to large and the crystal shape from xenomorphic to automorphic has been observed. At the same time, this paper also discussed the tendency of the changes of the crystal form, crystal grain size, the rate of crystallization etc. with the changes of corrosion time, pressure and the nature of corrosion solution. The preliminary results obtained from the research are of great significance in the counterevid-ence of the corrosion-crystallization processes of carbonate rocks in the nature, and of the formation and development regularity of karst, and in the study of diagenesis of carbonate rocks, in the asse-ssement of characteristics of karstfissure reservoirs of oil-gas-water.