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The Permian Fengcheng Formation of the Mahu Sag in the Jungar Basin is one of the most important hydrocarbon source rocks in Xinjiang oil field. The preservation of the geological records of Milankovitch cycles can be studied to understand the history of the Earth's evolution and sedimentary processes, and high‐resolution astronomical time scales (ATS) can be obtained by analysing (quasi) periodic sedimentary signals in geological records. In this study, the natural gamma ray (GR) and density (DEN) logging data are used to carry out a detailed spectrum analysis, including 2π‐Multi‐taper Method (MTM), Evolutive Harmonic Analysis (EHA), Correlation coefficient method (COCO) and DYNOT simulation. GR and DEN data analysis results show sedimentary cycles of 39.3, 9.1 m, 3.6–2.7 m and 2.1–1.7 m, 37.5, 9.7, 3.7 m and 2.4–1.9 m in MY‐1 well; MH‐15 well recorded the significant peaks at 81, 20, 8.6 m and 3.6–3.4 m and 66, 17.6, 6.8 m and 3.3–2.7 m; FN‐14 well revealed high‐confidence level frequencies with wavelength of 97, 23, 8.8 and 3.9 m and 88, 22, 8.5 m and 4–3.4 m respectively. The average sediment accumulation rates (SAR) are estimated at 9–9.7 cm/kyr for MY‐1, 14.5–19 cm/kyr for MH‐15, 13.5–14.5 cm/kyr for FN‐14 by using the COCO. In addition, we construct a continuous time scale for Fengcheng Formation, yielding a deposition duration of about 3.5 ± 0.2 Myr for these three drilling cores. Finally, we used the DYNOT sea‐level change model to analyse the GR and DEN logging series of three wells, for reconstructing the lake‐level changes of the Fengcheng Formation in the Junggar Basin. [ABSTRACT FROM AUTHOR]

[Display omitted] 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. [ABSTRACT FROM AUTHOR]