A synthesis of Carboniferous stratigraphy in Xinjiang, Northwest China with emphasis on regional and global correlations

Abstract

The Carboniferous is the most widely distributed system in the pre-Mesozoic strata of Xinjiang, Northwest China, and they are exposed in structurally independent units within various tectonic settings across the southwest Central Asian Orogenic Belt and Tarim Craton in Northwest China. According to the lithofacies associations and biotic assemblages, the Carboniferous successions of Xinjiang can be divided into 18 stratal regions, and each of these stratal regions may be further separated into several subregions in terms of lithology, biota, and geochronologic data. The depositional succession of each region is described on the basis of the key section. The marine fossils such as foraminifers (fusulinids), brachiopods, corals, and conodonts, as well as nonmarine fossils such as plants and pollens are reviewed in this study. Combined with the geochronologic data from the volcanic rocks and ash layers, a refined scheme of the Carboniferous successions in different regions across Xinjiang, Northwest China is obtained. The detailed and newly established stratigraphic framework of the Carboniferous strata could be very helpful for the regional and global stratigraphic correlations. It can also offer a new and reliable chronostratigraphic foundation for the comprehensive understanding of the tectonic evolution and petroleum exploration in Central Asia.