Diagenetic Facies Types and Semiquantitative Evaluation of Low Porosity and Permeability Sandstones of the Fourth Member

Key words: 
• diagenetic facies

Abstract: Diagenetic facies are results of diagenetic evolutions under special depositionl and diagenetic environments, including grains, cements, and textures integrated features. The study of diagenetic facies is important to low porosity and permeability sandstones in current exploration phases. This paper divided forth member of Xujiahe system of Guangan region into five diagenetic types, and set up the logging characteristics of each diagenetic facies. After single wells diagenetic facies analysis, this paper has semiquantitatively evaluated forth member of Xujiahe Formation of Guangan area by authorizing thickenss percentage content contour diagrams, thickenss content contour diagrams, areal distribution graph of diagenetic facies.