Organic Geochemical Characteristics of Mudstone and Marl from Western Hoh Xil Basin of Tibet

Research on mudstone and marl from the western Hoh Xil Basin, Tibet, reveals that these Tertiary lacustrine deposits formed under stratified, high-productivity conditions with a transition to more humid paleoclimate. Organic geochemistry analysis showed that organic matter originated primarily from bacteria, algae, and higher plants, with type II and III kerogen in mudstones indicating thermal immaturity, while marlite displayed type I-II1 kerogen at low to moderate maturity. Biomarkers, including odd-over-even predominance of long-chain n-alkanes and low Pr/Ph ratios (0.11–0.36), supported a reducing environment with stratified water columns. The study integrated sedimentary facies analysis, maceral composition, and carbon isotope data (δ13Corg) to reconstruct depositional conditions in the Miocene Wudaoliang Formation and Oligocene Yaxicuo Group.

Mi, W., Qi, X., Shang, Y., Kong, X., & Hu, Z. (2021). Organic Geochemical Characteristics of Mudstone and Marl from Western Hoh Xil Basin of Tibet. Geofluids, 2021, 1–15. https://doi.org/10.1155/2021/2235555