| The tectonic and environmental events had played an important role on the formation of the present-day global tectonic and environmental systems. This has been a attractive research field and most geoscientists pay attention to it. The tectonic evolution of China had undergone a significantly transition during Cretaceous. The Chinese topography has changed from high altitude in the east in the early Cretaceous into high altitude in the west in late Cretaceous. Simultaneously, the tectonic geodynamic system has translated from compression at N-S direction into E-W directional extension, the rift-related basins devolopped and the basin-range architecture occurred. However, the timing, process and the geodynamics of these transformations are not well understood. Liupanshan area, tectonically located in the center of Chinese continent, is a good laboratory to constrain these issues. Fatherover, as the northmost boundary of the Tibetan Plateau, the research on the deformation history of Liupanshan area during Cretaceous is available to knowledgement of the formation of the northeastern Tibetan Plateau.The present-day Liupanshan Mountain is mainly constructed by the Early Cretaceous Liupanshan Group. The Liupanshan Gr. are composed by the fluvial - lacustrine conglomerates, sandstones, mudstones, marls and limestones,with ca. 3000 meter in thick, which can be divided into five Formations from bottom to the top, the Sanqiao Fm., Heshangpu Fm., Liwaxia Fm., Madongshan Fm. and Naijiahe Fm.. The analysis of the rock magnetic measurement and the thermomagnetic behavior suggest that the primary remanent magnetization in these sedimentary rocks were mainly loaded by magnetite. Seven normal polarity zones and 8 reversal polarity zones are observed from the Huoshizhai section in the north of the basin. Analysis of combination of the magnetostratigraphic and paleontologic data reveal that the age of the Liupanshan Gr. spans from 129.6 to 102 Ma and the age of Sanqiao Fm. is ca. 129.6～128.6 Ma, Heshangpu Fm. is 128.6～125.3Ma, Liwaxia Fm. is 125.3～118.3Ma, Madongshan Fm. 118.3～109.6 Ma and Naijiahe Fm. is ca. 109.6～102 Ma. This proposes that two episodes tectonic uplift took place in the northmostern Tibetan Plateau in the Early Cretaceous, one episode initiated at least at ca. 130 Ma which induced the provenience of the sediments of Cretaceous Liupanshan basin, and the last one occurred after 102 Ma which resulted in the end of sedimentation of Cretaceous Liupanshan basin and the uplift of Liupanshan and adjacent area prior to the collision of India with Asia. Based on the analysis of the sedimentary sequence and facies from the Huoshizhai, Sikouzi and Shixianzi section in the north of the basin, eight basic stratigraphic sequence and four sedimentary systems (AST, LTST, LFST and LRST) were established. The magnetostratigraphic result combinated with the regional tectonic data depict that the Liupanshan basin was a rift-related depression basin and had undergone the early extension stage spanning 129.6～125.3Ma, middle expansion and stably depression stage during 125.3～109.6 Ma and later extinction stage during 109.6～102 Ma. The age of early extension stage is good to match with the time constraint well by the most studies of main duration of the tectonic extension in the east of China continent, indicative of this is the respondence to the lithospheric mantle detatchment and geodynamic system transformation in the east of Chinses continent.
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