| Based on the comprehensive analysis of cores, thin sections, well logging data and paleo-sedimentary setting, the types of sedimentary microfacies of Majiagou Submember-57 of Ordovician in northern Jingbian Gas Field of Ordos Basin are systematically summarized. Furthermore, guided by the theory of single factor analysis and multi-factor synthesis mapping, single factor contour maps of dolomite content, limestone content, granular dolomite content were selected, and the plane distribution of sedimentary facies in the study area are described in detail. It is indicated that:(1) the paleo-sedimentary setting of Majiagou Submember-57 of Ordovician in the northern part of Jingbian Gas Field show the characteristics of “alternation with uplift and depression”; (2) microfacies such as grain bank, dolomite flat, limy dolostone flat, and the depression of limestone developed; (3) the grain bank is favorable microfacies for high-quality carbonate reservoirs, which mainly distributes on the platform in the western Jingbian and the secondary uplift belt in the eastern Jingbian. |
