A survey of the Jurassic System of China

Abstract

Terrestrial Jurassic rocks are widespread in China, whereas marine Jurassic rocks are confined to Xizang (Tibet), South Qinghai, South Xinjiang, and, in limited parts of the sequence, to West Yunnan, Guangdong, South Hunan, and East Heilongjiang. Geographically, occurrences of Jurassic deposits may be divided into three regions and 13 districts: (I) the Xizang–Qinghai region, with the South Tethyan Himalayan, North Tethyan Himalayan, Lhasa, Xanza–Shiquanhe, Bangon–Dengqen, Karakorum–Tanggula, and Qamdo districts; (II) the Coastal Volcanic region of East China, with the Guangdong–Hunan, Fujian–Zhejiang, Heilongjiang, and Northeast China districts; and (III) the Stable Giant Basin region of West China, with the Sichuan–Yunnan and Northwest China districts. These regions and districts are described briefly, and preliminary biostratigraphic sequences and palaeogeography are presented. The upper and lower boundaries of the Jurassic System in China are briefly discussed.The Jurassic seas of China evidently were extensions of the Mediterranean (Tethyan) Sea and of the Pacific Ocean. The main transgressions occurred during Sinemurian, Bathonian–Callovian, and Tithonian – Early Cretaceous times. All three transgressions of the Mediterranean Sea were important, whereas only the earlier two transgressions from the Pacific Ocean were important.The relief and climate of China during the Jurassic Period are also discussed briefly. After Triassic tectonism, the ancient mountains, such as the Altai, Tian Shan, Kunlun, Altun, Hengduan, Qilian, Qinling, Dabei, North China Plateau, Huaibei Plateau, and Yunnan–Guizhou Plateau, originated. Latitudinal and longitudinal tectonic belts were important in the geological development of China and significantly influenced biogeography, palaeogeography, and climate.