Fig. 1

(a) Regional tectonic setting of the Ordos Basin within the North China Platform. (b) Stratigraphic framework of the Ordovician strata in the western margin of the Ordos Basin
(a) Regional tectonic setting of the Ordos Basin within the North China Platform. (b) Stratigraphic framework of the Ordovician strata in the western margin of the Ordos Basin