关键词: 侏罗系, 古地理, 古气候-古生物群落, 裂谷型断陷-坳陷盆地, 内陆坳陷盆地, 山间盆地

Abstract: Based on the characteristics of tectonic setting, palacogeographic outline, sedimental lithofacies and stratigraphic sequence in China, the study and analysis of distribution sequencc and lithofacics of Jurassic and its petroliferous geologic conditions has been made. The Jurassic sedimentary provinces, bounded with Helan Mt.-Longmen Mt.-Kangdian uplift-Ailao Mt. are divided by the authors into eastern and western parts. The east is dominated by north-east, north-north-east oriented faulted basins, the west by near cast-west oriented intermontane besins. In early Jurassic, the coastline area in the east became a part of the Pacific, while the inland province became rift faults-depressions and inland depressed basins; Xizang(Tibet) area in the west was marine sedimentary province, Xin-jiang was inland one while the others were all intermontane basin sedimentary province. In late Jurassic, as uplifting of the castern contincntal crust and the Pacific plate subducted toward the continent, fierce volcanic activities occurred in thd east, forming a large of volcanic rocks or volcanic-sedimentary rocks in the basins. During that period, Xizang province remained as the same, but the occan area became smailer, the other basins would become shallower as a result of crust uplifting and long-term depositing, thus a set of red clastic substances were formed. Having analyzed tectonic setting and sedimentary environment of Jurassic, the authors point out that Jurassic is not only a dominant coal-generated sequence, but also is an important petroliferous one, having extensively favorable petroliferous prospects.

Key words: Jurassic, Palaeogeography, Palcoclimate-paleobiocoenosis, Rift fault-depression basin, Inland depressed basin, Intermontane basin