Anomalous weathering trends indicate accelerated erosion of tropical basaltic landscapes during the Permo-Triassic warming
Anomalous weathering trends indicate accelerated erosion of tropical basaltic landscapes during the Permo-Triassic warming
复制标题
异常风化趋势表明二叠纪-三叠纪变暖期间热带玄武岩景观加速侵蚀
DOI：
10.1016/j.epsl.2021.117256
复制
发表时间：
2022-01
影响因子：
5.3
通讯作者：
Dongxun Yuan
中科院分区：
文献类型：
--
作者：
Jianghai Yang;Peter A. Cawood;Dan J. Condon;Jianzhong Liu;Xusheng Deng;Jingfu Wang;Yuansheng Du;Dongxun Yuan
热带环境中玄武岩的风化作用对气候变化非常敏感，对气候演化具有重要的调节作用。虽然在现代地球上进行了广泛的研究，并假设地质过去，但玄武岩风化很难在地质档案中直接追踪。本文对峨眉山大火成岩省玄武岩沉积物进行了有机碳含量、同位素组成、矿物组成和地球化学组成的测定。根据新近获得的高精度锆石U-Pb年龄（251.79 ± 0.12/0.13/0.36 Ma），建立了峨眉山LIP玄武岩景观在二叠纪-三叠纪快速气候变暖期的风化强度时间变化。风化趋势分析表明，在整个二叠纪-三叠纪过渡期的风化强度显着下降。这种强度的下降是异常的，考虑到它与二叠纪-三叠纪过渡期的气候变暖相吻合，这往往会提高玄武岩的化学风化速率，并产生具有高化学风化强度的沉积物。将这些风化趋势与当今玄武岩风化-温度关系和报道的古温度相结合，定量估计总侵蚀速率从最晚二叠世的282 ± 43 t/km 2/yr增加到早三叠世的> 1618 ± 187 t/km 2/yr。这种大规模的侵蚀在早三叠世可能与放大极端降水与加强水文循环在早三叠世温室气候。这项研究强调了热带景观对快速气候变暖的风化反应。
Weathering of basalt in tropical environments is sensitive to climate change and considered to play a significant role in regulating climate evolution. Though extensively studied on the modern Earth and hypothesized for the geological past, basalt weathering is difficult to directly track in geological archives. We here focus on the basaltic sediments derived from the Emeishan large igneous province (LIP) in South China and determined their organic carbon content and isotope, mineral and geochemical compositions. Based on the newly obtained high-precision zircon U-Pb age of 251.79 ± 0.12/0.13/0.36 Ma, we establish temporal variations of weathering intensity for the Emeishan LIP basaltic landscapes in the tropical latitudes through the Permo-Triassic rapid climate warming periods. Analysis of weathering trends indicates a significant decrease in weathering intensity across the Permo-Triassic transition. This decrease in intensity is anomalous considering its coincidence with the climate warming at the Permo-Triassic transition, which tends to elevate chemical weathering rate of basalts and produce sediments with high chemical weathering intensity. Combining these weathering trends with present-day basalt weathering-temperature relationship and reported paleo-temperatures, total erosion rate is quantitatively estimated to increase from 282 ± 43 t/km2/yr in the latest Permian to > 1618 ± 187 t/km2/yr in the Early Triassic. This massive erosion in the Early Triassic is plausibly related to amplified extreme precipitation associated with intensification of the hydrological cycle in the Early Triassic hothouse climate. This study underlines the weathering responses of tropical landscapes to rapid climate warming.
登录
查看更多内容
峨眉山火成岩省晚期硅质火山作用的碎屑记录
影响因子：
6.1
作者：
Deng Xu-Sheng;Yang Jianghai;Cawood P.A.;Wang Xuan-Ce;Du Yuansheng;Huang Yan;Lu Shu-Fan;He Ben
通讯作者：
He Ben
影响因子：
5.8
作者：
Yigang Xu;B. He;Sun‐Lin Chung;M. Menzies;F. Frey
通讯作者：
Yigang Xu;B. He;Sun‐Lin Chung;M. Menzies;F. Frey
影响因子：
4.9
作者：
A. Naidu;T. C. Mowatt
通讯作者：
A. Naidu;T. C. Mowatt
影响因子：
2.3
作者：
PARKER, A
通讯作者：
PARKER, A
影响因子：
6.1
作者：
Martin Schobben;M. Joachimski;D. Korn;L. Leda;C. Korte
通讯作者：
Martin Schobben;M. Joachimski;D. Korn;L. Leda;C. Korte