Analysis of Formation Water Characteristics of Chang 6 Reservoir in WLW Area

Taking Chang 6 reservoir, the main reservoir of Triassic in WLW area, as the research area, the characteristics of formation water are analyzed by studying its formation water detection data. The results show that the content of cation Na+ + K+ in formation water in this area is the highest, followed by Ca2+, Mg2+ and a small amount of Ba2+. The content of Cl-in anion is the highest, followed by HCO3−, containing a small amount of CO32−. The average salinity in this area is 34.34 g/L. The salinity has a significant correlation with Cl−, and the formation water is CaCl2 water type. Through the screening of formation water data in this area, the characteristic parameters of formation water ion combination in this area are finally calculated. Among them, the average sodium chloride coefficient is 0.72, the average desulfurization coefficient is 0, the average calcium magnesium coefficient is 0.10, and the average metamorphic coefficient is 25.8. The values of the characteristic parameters of each ion combination indicate that the Chang 6 reservoir in the WLW area has good sealing and is a favorable place for oil and gas storage.