Keywords: 
• Quantitative microfacies analysis

Abstract: The Strata of Qixia Formation is well developed in ChaohuNanling Area of Anhui Province, with constant thickness, high content of organic matter and the porosity. Previousy study of the carbonate  Qixia Formation in this area is essentially qualitative. Therefore, quantitative microfacies analysis of the carbonate in Qixia Formation is significant to confirm the sedimentary facies, predict and explore the gas and oil. In Qixia Formation, the first member deposits in the middle carbonate slope, with the highest grain, opensea biota content and grain/matrix ratio, which are 35.65%, 0.43% and 0.70, respectively; The second member deposits in lower carbonate slope, with the lowest grain content, grain/matrix ratio, which are 24.69% and 0.38, and also highest opensea biota content, that is 0.43%; The third member deposits in open carbonate platform, with higher grain and the lowest opensea biota contents, which are 32.68% and 0.34%, respectively. The fourth member deposits in middleupper slope, with higer grain content and grain/matrix ratio, which are 29.91% and 0.52, respectively, and the content of opensea biota is 2.39%. This conclusion is consistent with the previous one, further supporting the previous research. 