XIE Qi-feng1,3, ZHOU Li-fa2, CAI Yuan-feng3, LIU Yu1, LIU Zhi-wu4
1. College of Zijin Ming, Fuzhou University, Fuzhou 350116, China;
2. Department of Geology, Northwest University, Xi'an 710069, China;
3. State Key Laboratory for Mineral Deposits Research, Nanjing University, Nanjing 210046, China;
4. School of Earth Science and Resource, Chang'an University, Xi'an 710054, China
Abstract: This study focused on the Permian mudstones geochemistry in the Xiariha depression, south Qilian basin, their implications to sedimentary environment, tectonic setting, and provenance attribute. On the basis of the organic and inorganic geochemistry, we discussed the total organic carbon content, hydrocarbon potential, maximum temperature, major and rare earth elements, and other features. The results showed that: The Permian mudstone organic has higher maturity, produced mainly by aquatic and aquatic-terrestrial mixed organisms, which live in the depositional environment of semi-enclosed, hypoxia, moderate reduction and salinity water bodies. The P2c kerogen of Ⅱ2-Ⅲ type, whose parent material came from marine plankton and microorganisms, is the main source rock in the study area, while the P3q, which is the terrestrial materials derived lower maturity type Ⅲ kerogen, is the potentially source rock. The mudstone tectonic setting originates from active continental margin tectonic setting, and the mudstone shows a great affinity with felsic rocks in the upper crust of the Middle Qilian uplift and the mixture of andesitic rocks.
Keywords: South Qilian Basin Permian source rocks geochemistry sedimentary environment tectonic setting provenance attribute
*Corresponding Author, E-Mail: xieqf@fzu.edu.cn
Bulletin of Mineralogy, Petrology and Geochemistry Vol. 34, No.2, 2015, page 354-361
