Advent of Strong South Asian Monsoon by 20 Million Years Ago

作者：Retallack, Gregory J.^*; Bajpai, Sunil; Liu, Xiuming; Kapur, Vivesh Vir; Pandey, Santosh Kumar

来源：Journal of Geology, 2018, 126(1): 1-24.

DOI：10.1086/694766

• HIMALAYAN FORELAND BASIN
• PEDOGENIC CARBONATE HORIZON
• LATE MIOCENE
• LATE EOCENE
• PALEOCLIMATIC IMPLICATIONS
• INDIAN SUBCONTINENT
• ISOTOPE COMPOSITION
• KASAULI FORMATION
• TIBETAN PLATEAU
• ORGANIC-CARBON

The monsoonal paleoclimate of India has been critical for understanding the tectonic history of Himalayan and Tibetan uplift over the past 60 My. Monsoonal circulation in deep time has been inferred from variation in stable isotopes of tooth enamel, diatom blooms, and dust influx in the Indian Ocean and the advent of C-4 grasses, but these proxies are compromised by temperature, biotic, and source effects. Our study uses a proxy of carbonate distribution within paleosol profiles to infer appearance of monsoonal circulation of modern strength in the Himachal Pradesh segment of the Himalayan foreland by at least 20 My ago, cued to High Himalayan deformation and ongoing Tibetan Plateau uplift and retreat of the Paratethys Sea. Paleosol records also demonstrate declining chemical weathering with Himalayan and Tibetan uplift, which was a force for global warming, rather than cooling, over the past 20 My.

• 出版日期2018-1
• 单位福建师范大学