The role of volcanism in the genesis of Early Cenozoic global warming events

了解快速全球变暖的原因和后果的一种方法是研究地质变暖事件-称为“高温”-反复打断了新生代早期（~60-52 Ma）非常温暖的气候状态。控制高温气流发生的一种假说是，它们是由与北大西洋火成岩省（NAIP）有关的火山活动在~60-50 Ma期间触发的。这些火山脉冲可能通过直接释气或岩浆侵入对富含有机物的岩石进行热蚀变而将二氧化碳输送到大气和海洋中。虽然这些关系已经测试了最大的始新世超热，古新世-始新世热最大（PETM），岩浆侵入，热CO2释放之间的关系，以及许多随后的早始新世超热事件的成因仍然未经测试。了解火山活动是否是引发高温的原因是一项重要的任务，以量化每次事件期间释放的CO2量;并量化CO2强迫和温度变化之间的关系（气候敏感性）。这个博士项目将应用尖端的代理数据技术来识别地质记录中的火山活动，记录一系列全球分布的沉积序列早始新世超热事件。沉积汞浓度将被用来重建与NAIP从~60-52马的火山活动的历史。其次，利用海相岩石的锇同位素组成，追踪火山源锇在海洋化学上的全球地球化学指纹。

One approach to understanding the causes and consequences of rapid global warming is to study geological warming events - called 'hyperthermals' - that repeatedly punctuated the very warm climate state of the early Cenozoic Era (~60-52 Ma). One hypothesis for a control on the occurrence of hyperthermals is that they were triggered by volcanism associated with the North Atlantic Igneous Province (NAIP) in the interval ~60-50 Ma. These volcanic pulses could have delivered CO2 to the atmosphere and oceans either by direct outgassing, or by the thermal alteration of organic-rich rocks by magmatic intrusions. Although these relationships have been tested for the largest Eocene hyperthermal, the Paleocene-Eocene Thermal Maximum (PETM), the relationship between magmatic intrusions, thermogenic CO2 release, and the genesis of the many subsequent Early Eocene hyperthermal events remains untested. Knowing whether volcanism was responsible for triggering hyperthermals is an important task, to quantify the amount of CO2 released during each event; and to quantify the relationship between CO2-forcing and temperature change (climate sensitivity). This PhD project will apply cutting-edge proxy-data techniques for recognizing volcanism in the geological record, to a series of globally distributed sedimentary successions recording Early Eocene hyperthermal events. Sedimentary mercury concentrations will be used to reconstruct a history of volcanism associated with the NAIP from ~60-52 Ma. Secondly, the osmium-isotope composition of marine rocks will be used to trace the global geochemical fingerprint of volcanic-derived Os on ocean chemistry.