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报告题目：Volcanic trigger of ocean deoxygenation during Cordilleran ice sheet retreat 科迪勒拉冰盖消退过程中火山活动所触发的海洋缺氧事件 主讲人：杜江辉 博士 苏黎世联邦理工学院 地球化学与岩石学研究所 Abstract: North Pacific deoxygenation events during the last deglaciation were sustained over millennia by high export productivity, but the triggering mechanisms and their links to deglacial warming remain uncertain. Here we find that initial deoxygenation in the North Pacific immediately after the Cordilleran ice sheet (CIS) retreat was associated with increased volcanic ash in seafloor sediments. Timing of volcanic inputs relative to CIS retreat suggests that regional explosive volcanism was initiated by ice unloading. We posit that iron fertilization by volcanic ash during CIS retreat fuelled ocean productivity in this otherwise iron-limited region, and tipped the marine system towards sustained deoxygenation. We also identify older deoxygenation events linked to CIS retreat over the past approximately 50,000 years. Our findings suggest that the apparent coupling between the atmosphere, ocean, cryosphere and solid-Earth systems occurs on relatively short timescales and can act as an important driver for ocean biogeochemical change. 会议时间： 2022年11月11日 下午 4:00- 会议地点： 腾讯会议室 577-231-521 主办单位：北京大学地球与空间科学学院 北京大学海洋研究院 & _1 q$ d; Z& Q& ]" {; |; C
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