Abstract:Geomorphological and sedimentological data indicate that the Daqingshan Mountains experienced uplift- denudation in the late Early Cretaceous, the early Late Cretaceous, and the Cenozoic since the Late Mesozoic; However, previous apatite fission track (AFT) research only revealed two stages of uplift- denudation events for the basement of the northern Daqingshan Mountains during the early Late Cretaceous and since the Miocene. AFT results were reported in this study performed on six Paleoproterozoic granitic samples, in order to clarify the uplift- denudation processes for the basement of the southern Daqingshan Mountains. Six AFT ages vary between 119±8 and 79±5 Ma with altitude difference of ca. 700 m, but show no clear correlation with altitude. Mean track lengths range from 13. 2±2. 2 to 11. 8±1. 8 μm with unimodal distributions. Thermal history modeling results indicate three stages of uplift- denudation events for the basement of the southern Daqingshan Mountains: the late Early Cretaceous (from ca.120 Ma to ca.110 Ma), the early Late Cretaceous (from ca.100 Ma to ca.90 Ma), and the Cenozoic (since ca.34 Ma to ca.15 Ma). Combined with structural, sedimentary, and geomorphological data in the region, together with the comparisons to the basement of the northern Daqingshan Mountains, the timing of the late Early Cretaceous event agrees well with that of the rapid cooling of the ductile shear zone, indicating the same driving mechanism; the early Late Cretaceous event corresponds well with the contemporary whole uplift- denudation of the Yinshan- Yanshan intracontinental orogenic belt; the Cenozoic event is likely to be related to the activities of the southern piedmont normal fault. The event for the basement of the southern Daqingshan Mountains since the Cenozoic is likely to be earlier than that for the basement of the northern Daqingshan Mountains, suggesting that the northern piedmont normal fault start later than the southern piedmont normal fault. Compared to data in the Beishan, Beidashan, Langshan, Yanshan, Greater Hinggan Mountains, and central Inner Mongolia Plateau, the rapid uplift- denudation event in the late Early Cretaceous in the Daqingshan Mountains is more likely related to the post- orogenic collapse after the closure of the Mongolian- Okhotsk Ocean; the rapid uplift- denudation event in the early Late Cretaceous is more likely affected by the subduction of the Pacific plate; the distant effect of the collision between the Indian and Eurasian plates probably plays a major role in the rapid uplift- denudation in the Cenozoic.