| This dissertation focuses on the terrestrial strata sequences during thelate Cretaceous- Paleogene period of the Hoh Xil, Qiangtang, and Cuoqin basin in theTibetan Plateau hinterland, where the research degree lags relatively behind, and thedetail studies on stratigraphy, lithology, sedimentary facies, source region analyis,apatite fission track dating and oil-gas reservation process has been carried out. Themain conclusions and progress are as follows:On the basis of former results of geology branch of Qinghai and Tibet province,the pollen proxies and the ESR dating, together with the areal geology investigationon 1:250 thousand scales and the latest geology investigation research of CNPC,consulting the recent geomagnetism dating results in Cenozoic Hoh Xil and TuoTuoriver basin, the epoch of terrestrial Fenghuoshan group belongs to the Eocene- earlyOligocene period and the age is about 51.0～31.5Ma; In according to the study onstrata sequence of Abushan series, the unconformity relation between the Abushanand underlayers, pollen proxies and the ESR dating in Qiangtang basin, the Abushanseries is set to the late Cretaceous stage; As for the Jingzhushan seires in the Cuoqinbasin, it belongs to the late Cretaceous stage.According to further study on the lithology, sedimentary tectonic features andspatial distribution character, Fenghuoshan group is defined as the Fluvial depositionsystem, fan delta deposition system, lacustrine deposition system and the lacustrinefan deposition system, Abushan series belongs to the combined deposition system ofalluvium fan, fluvial sediment, fan delta system and the shallow lake system, andJingzhushan series show large similarity with the Abushan series, which is justcharacteristic of carbonate deposition of ocean transgression process locally.The provenance for the Fenghuoshan group is mainly proximal continentalsedimentary rock regions and the paleocurrents were dominantly to northeastward.The conglomerate of Abushan series hails from the Central Uplifting Zone, theprovenance comes from the southernwest Central Uplifting Zone, which based on theclastic composition of sandstone for the Abushan series of Shuanghu Tuonamu region,and the paleocurrents were dominantly to northeastward. The paleocurrents of Jingzhushan series were begin to southwestward and afterward to northeastward,which shows the direction of palaeocurrent is transformed and related to the tectonicfunction and evolution for foreland basin.Within the Hoh Xil basin, seven out of nine sedimentary samples deposited in thePalaeogene yield apparent fission track ages are～47-～36Ma (Eocene), they areapproached to the stratigraphic timescale, whose mean track lengths are variable butcentred on～12.8μm, which shows the sedimentary samples didn't experience whollyannealing. The fission track results combined with stratigraphic constraints from theHoh Xil Basin suggest maximum palaeo-temperatures between～100℃and～120℃were experienced in the Oligocene by most of the sediments sampled in this study.Rapid denudation beginning in the Palaeogene followed by a change to slowerdenudation in the Eocene-Oligocene is suggested by the apatite fission track resultsfrom the Tanggula Mountains, and is consistent with reduced erosion in the Hoh Xilregion from the Miocene to Recent implied by the northeast advancing deformationfront model. The cooling of Qiangtang basin is focused on two timescales, they areOligocene and Cretaceous.Based on the above investigation, the dissertation studies the time and thefunction for the inverted structure of hinterland of the Tibet Plateau, which expressesthe time for inverted structure was early to the time for Oil-forming height peak andthe oil source rock, the large anticlines structure of Qiangtang basin are mainlyformed between late Jurassic and early cretaceous, therefore, the essential elementswere spatially well deployed, and temporally, petroleum-forming processes also hadgood relationship. After later cretaceous, the hinterland as a whole becameProto-Tibetan Plateau, benefit to the oil-gas reservation...
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