应闫义研究员邀请， 伦敦大学学院地球科学系Peter D. Clift教授将于9月9日（周二）访问我所并在综合楼602会议室做学术报告，欢迎大家参加并积极讨论！

        报告题目：Mountain Building, Erosion, Chemical Weathering, Carbon and Neogene Global

        报 告 人：Peter D. Clift教授
        报告时间：9月9日（周二）上午10:00
        报告地点：综合楼602会议室    

       报告人简介：            

      Peter D. Clift教授现任伦敦大学学院地球科学系教授，并荣获皇家学会-沃尔夫森研究员荣誉。他主要从事大陆边缘地层发育、亚洲季风演化以及构造运动、地表过程和气候变化之间相互作用等研究。他曾获得多项国际荣誉，包括美国地球物理联盟（AGU）会士、美国地质学会会士、伦敦地质学会Lyell奖章、伦敦地质学会Murchison奖、中国科学院国际访问学者奖学金等。他曾参与多次国际大洋钻探计划（IODP）航次,并曾担任IODP 355航次首席科学家。他的学术成果显著，成果主要发表于Nature, PNAS,Nature Geoscience, Nature Communications, Geology和EPSL等国际高水平刊物上，总引用数超过27000次。

        报告摘要：       

Reconstructing terrestrial environments is critical if we are to understand the development of major climatic systems. Unfortunately, terrestrial records are often incomplete and hard to date and usually represent a small fraction of the total eroded from mountain belts. However, the clastic record delivered to the oceans provides an archive for looking at large scale environmental change. I applied spectral analytical techniques to look as environmentally sensitive minerals hematite and goethite to reconstruct how seasonality and moisture have changed across Asia and northern Australia during the Neogene. The best records are preserved in hemiplegic sequences rather than turbidite-rich submarine fans. The area has dried since the Mid Miocene, especially during the Late Miocene, with a more recent phase of variable and sometimes wetter, more seasonal conditions during the Plio-Pleistocene. Environments in Australia are decoupled from those in Asia due to the influence from the Indonesian Throughflow, as well as the northward drift of Australia. 

Comparison of humidity records with rates of erosion indicate faster erosion during wetter time intervals, as well as at times of rapidly changing climate. The degree of chemical alteration of sediment reaching the ocean does not have a linear relationship with total rainfall because heavy rains result in rapid transport and little time for chemical alteration in floodplains. The total amount of atmospheric CO2 consumed as a result of chemical weathering of the eroded sediment is more strongly linked to the total amount of sediment rather than the degree of alteration experienced prior to sedimentation. Source composition is also critical. This means that fast erosion of the Himalaya and SE Asian islands in the Plio-Pleistocene drove rapid drawdown of CO2 which may have been important in intensifying global cooling. However, an erosional pulse inferred for the Middle Miocene correlates with a warm, wet period although it may help to drive cooling after the Mid Miocene Climatic Optimum. A synthesis of geochemical records from marine depocentres around Asia combined with regional seismically derived sediment budgets is essential if we are to reconstruct the changing environment in monsoon or Asia and assess its influence on global climate.