[S-CG41] 地殻表層の変動・発達と地球年代学／熱年代学の応用

[SCG41-02] Cenozoic mountain building in eastern China and its correlation with reorganization of the Asian climate regime

★Invited Papers

*Jingxing Yu¹、Dewen Zheng¹、Jianzhang Pang¹、Ying Wang¹、Peizhen Zhang² (1.Institute of Geology, China Earthquake Administration、2.Sun Yat-Sen University)

The Cenozoic Asian climate system experienced a transformation from a zonal pattern to a monsoon-dominant pattern around the Paleogene-Neogene boundary. A series of dynamic mechanisms, such as uplift of the Tibetan Plateau, retreat of the Paratethys Sea, expansion of the South China Sea, and decreasing atmospheric CO2 content, has been suggested to be responsible for the transformation of the Asian climate pattern. However, the role of topographic growth in eastern China has been rarely considered. As the natural divides of geography, climate, and biology, the two most distinct sets of topographic relief in eastern China, the Qinling and Taihang Mountains, play an important role in shaping the Asian climate pattern. We report low-temperature thermochronology data from the Qinling and Taihang Mountains and use age-elevation relationships and thermal history modeling to show that both mountain ranges experienced a phase of rapid exhumation during the late Oligocene and early Miocene. The building of the Qinling and Taihang Mountains around the Oligocene-Miocene boundary temporally and spatially coincided with the reorganization of the Cenozoic Asian climate regime, suggesting that the mountain building in eastern China acted as a possible driving mechanism for the alleged reorganization of the Cenozoic Asian climate regime.