Cenozoic tectonic evolution of the Liupan Shan area:Evidence from zircon and apatite fission tracks
The uplift and expansion of the Tibetan Plateau not only resulted in strong deformation in the Eurasian continent,but also had a significant impact on the geomorphic pattern and climate change around the plateau.The uplift of its northeastern margin since the Cenozoic has been a subject of controversy,with the age of uplifted mountains in the northeastern plateau being a key factor in resolving this debate.To further determine the uplift age of Liupan Shan and its surrounding areas,we conducted apatite and zircon fission track analyses and thermal history inversion in the Longzhong Basin,Liupan Shan fold and thrust belt and the southwestern margin of Ordos block.The results of the apatite fission track tests reveal that the ages of apatite fission track in the bedrock samples from the study area range from 136 to 16 Ma,with track lengths ranging from 11.9 to 13.3 μm.Zircon fission track ages range from 258 to 79 Ma,with the majority falling between 160 and 99 Ma.The thermal history models based on the apatite fission track data indicate that the Liupan Shan area experienced at least two periods of cooling events during the Cenozoic era.The first period occurred during the Eocene(55～30 Ma),while the second period occurred since the Middle Miocene(17～12 Ma).The uplifting during the Eocene may be attribute to a rapid response to the collision between Indian and Eurasian continents,which had a far-reaching effect on the region.The more recent uplifting events since the Middle Miocene are likely associated with tectonic activities that shaped the current tectonic framework in the northeastern Tibetan Plateau.
Northeastern margin of the Tibetan PlateauLiupan ShanTectonic evolutionLow temperature thermochronologyFission track
万方数据
维普
