EVIDENCE FROM APATITE AND ZIRCON FISSION TRACK ANALYSIS FOR MESOZOIC-CENOZOIC UPLIFT THERMAL HISTORY OF BOGEDA MOUNTAIN OF XINJIANG,NORTHWEST CHINA

Fission-track dating evidences from 5 apatite samples and 4 zircon samples and modeled time-temperature thermal history indicate that the uplift process of Bogeda Mountain since late Jurassic-Cretaceous can be divided into four stages:150~106,75~65,44~24 and 13~9 MaBP.Before 44~24 Ma,the cooling rate and uplifting rate of the southern and northern segments of Bogeda Mountain were the same,but since 44~24 MaBP,the uplifting of the southern and northern segments of Bogeda Mountain has become different.During 42~11 Ma,the northern segment was in a steady stage,with the cooling rate being 0.03℃/Ma and uplifting rate 1 m/Ma.During 11 Ma-present,the northern segment was in a rapidly cooling and uplifting stage,with the cooling rate being 5.72℃/Ma and uplifting rate 190.6 m/Ma.The southern segment was in a rapidly cooling and uplifting stage since 26 Ma,with the cooling rate being 1.24℃/Ma and uplifting rate 41.2 m/Ma during 26~9 Ma and 4.88℃/Ma and 162.9 m/Ma during 9 Ma-present.The difference in the uplifting may be because of collision between the Indian and Eurasian plates and also of being controlled by the processes of dynamics at different depths of Bogeda Mountain.