Based on the sedimentary features and facies change of the Upper Jurassic in Mohe basin and supported by many other evidences

it is proposed for the first time that the late Jurassic Mohe basin is a molasse basin controlled by the Yanshanian intracontinental orogeny

which was caused by the activation of the fossil suture zones related to subduction of the Mongolia-Ochotsk ocean.Three stages of the development of the basin have been established and the northward migration feature of its dynamic evolution has been identified.At the end of Jurassic the basin closed and was reformed by the W-E trending thrusts(the main deformation episode) along with continent-continent collision.From the Cretaceous to the Eogene

two phases of reformation happened in the basin and their structure features are nearly NNE trending transtentional faults

with at least three deformation episodes recognized and W-E trending normal faults.In terms of oil and gas exploration potential

the central

eastern

and southern part of the basin are more promising than the rest parts of the basin.