Origin of calcite cements and their impact on reservoir heterogeneity in the Triassic Yanchang Formation, Ordos Basin, China: A combined petrological and geochemical study

Calcite cement is a typical product of fluid–rock interaction in petroleum reservoirs, and its migration has a major impact on reservoir heterogeneity. A case study of a closed diagenetic system was carried out on the Upper Triassic Yanchang Formation of Ordos Basin, China—the most successful exploration region for tight sandstone oil in China. The investigated sandstones are mainly lithic arkoses (Q31F42L27). Three occurrences of calcite cement...