Effectiveness of the Acidizing Treatment in Wells Based on the Petrographic Results of Thin-Section Acidizing Experiments

The acidizing treatment is a method usually used for the enhancement of productivity in oil-gas fields. Treating thin-sections for microscopic petrographic analyses with common acids, establishes the solubility and dispersion of minerals, as well as secondary formation damage. The best results were achieved by treating carbonate rocks and rocks with carbonate constituents. Siliceous minerals, such as quartz and micas are not dissolved, but the solubility of feldspars increases with the Ca-component in plagioclase and thc degree or alteration. Clay minerals are subject to mechanical disintegration which causes further formation damage. Anhydrite and opaque minerals are insoluble.