Abstract:Unlike the North China Craton, the eastern part of which commonly contains NEtrending faults, the Luxi Block hosts one group of welldeveloped NWtrending faults with obvious geological features, including nonbasincontrolled faults and basincontrolled faults. The former is located in the south end of the Luxi Block, with relatively large dipping, and cuts through the Paleozoic and underlying strata. Ductile shear zone occurs in the lower Archaean footwall, with faulting fragments indicating multiple activities. The latter located in the north of the nonbasincontrolled faults, except the Mengshan fault, has underdeveloped ductile shearing zone and relatively flat dip, which controls the sedimentation since the Mesozoic. Apatite/zircon fission track analysis show that there existed some differences in activity of the NWtrending faults. The apparent ages of apatite fission track for the samples from hanging wall and footwall are 67±5Ma and 35±2Ma, respectively, and the track histogram shows that the samples were not subject to thermal disturbances during the cooling process. The activity time of the faults is restrained using the average track lengthage (or banana diagram), single grain peak age, track age spectrum pattern and thermal history inversion simulation. The results show that the nonbasincontrolled faults might start activity in the Early Jurassic of about 184Ma, and continued to be active in the Late Cretaceous 80~75Ma and the Cenozoic ca.61Ma and 51~43Ma, and might cease after 43Ma. The basincontrolled faults started active relatively late, probably in Early Cretaceous ca.141Ma, Late Cretaceous 80~75Ma, and was active in about 61Ma, 49~42Ma and 36~32Ma during the Cenozoic period. In general, the NWtrending faults developed chronologically from south to north. The nonbasincontrolled faults were active early but ceased early; while the basincontrolled faults were active late but ceased later and controlled northward development of the depression. Changing of regional tectonic stress field and strikeslipping of the TanLu fault zone since the Mesozoic was the fundamental causes for the evolution divergence of two types of NW faults. Deep part of the faults was controlled by continentcontent collision of North China and Yangtze plates in the Late Triassic, as well as direction and speed change of paleoPacific plate subduction. The Indosinian transition from compression to extension, coupled with the sinistral strikeslipping of the Tanlu fault zone, gave the top priority to the development of NWtrending faults near the southern margin of the North China Craton. Because the large dip angle failed to control the development of the basin, the faults extended relatively toward north end, forming basincontrolled faults. After extension in the Early Cretaceous (ca.141Ma), the faults finally gradually took a shape at end of Late Cretaceous (ca. 80~75Ma) and in the Cenozoic. The generally northward migration of the NWtrending faults suggests that destruction of the North China Craton may initiate in the Early Jurassic or Late Jurassic and delaminated gradually from south to north.