Discovery of Late Carboniferous strata and their tectonic significance in the southern margin of the North China Block (Huoqiu and Gushi areas)

Abstract

Late Carboniferous fossils (such as Boultonia? sp., Tabulata, and spiriferoid specimens with smooth shells), bioclastic material (such as crinoid stems and sponge fragments), and Late Ordovician microfossils of the conodont Belodina have been discovered in the lower part of the strata typically referred to as the Neoproterozoic on the boundary of the provinces of Anhui and Henan in the southern margin of the North China Block. These findings prove that the strata contain macrofossils belonging to the Late Carboniferous, which belonged to a carbonate debris flow deposit that was formed under a carbonate slope environment. The conodont fossils might belong to a detrital deposit. Thus, it is possible to reset the stratigraphic sequences and tectonic attributes belonging to the North Huaiyang tectonic belt and limit the Shouxian fault to the boundary between the Dabie Orogen and North China Block.