基岩区全新世活动断层的活动时代与速率的确定一直是活动构造研究的一个重点和难点，同时也是古地震学家急需解决的一个挑战问题。因此，本申请拟选择河套盆地周缘典型岩石暴露地貌面和全新世基岩正断层面，借鉴国外就地宇宙成因14C测年研究经验，开展就地宇宙成因14C测年探索研究，尝试建立适合我国古地震研究的就地宇宙成因14C测年流程，探索应用就地宇宙成因14C研究基岩区正断层活动时代与速率的可能性，为基岩地区活动构造的研究提供一种新的途径。

The age and slip rate of Holocene normal fault have been an undoubtedly challenge for seismologists to be yielded as result from lack of appropriate late Quaternary sediment. Accordingly, the main purpose of this project is to develop in situ cosmogenic 14C dating based on published report and our own experenice in AMS 14C dating and examined by the known age sample collected from exposed bedrock surface around Hetao basin. On the other hand, in situ cosmogenic 14C dating of preserved, seismically exhumed normal fault scarps was used to identify the last few major earthquakes on Langshan faults and recover their ages and displacements through the modelling of the content of in situ 14C dating of the scarp rocks. The inferred result was compared with the data yielded from historical document and trench methods to find the limitations and parameters that affect the resolution of the inferred recent rupture history along these types of faults. The main outcome of this project will be the testing and proving of a alternative way to recover past earthquakes, their timing, and the regularity of their recurrence for preserved, seismically exhumed normal fault scarps especially in western China.