Miocene sea-level change and carbon cycling: New Jersey shallow shelf Expedition 313

中新世早期/中期，距今2400万年至1400万年，代表着当今冰屋世界发展的一个重要阶段。具体地说，地球的气候系统在相对凉爽和相对温暖的状态之间振荡，直到南极冰川在中新世后半段牢固确立。根据从深海沉积物获得的地球化学数据，这些气候振荡的特点是海平面变化和碳埋藏模式的变化相一致，并推断在海平面低水位期间碳埋藏增加。在中新世浅层海洋沉积物中进行钻探(IODP Expedition 313)提供了一个机会，以评估海洋记录中的证据是否通过对这些近岸沉积序列的分析而得到证实，这些序列预计(在这个古老稳定的大陆边缘)对全球海平面的变化非常敏感。最近关于较老地质层段的工作证明了陆地有机质作为大气二氧化碳碳同位素组成的档案的潜力，这是对沉积储集层碳埋藏和释放的监测。这项拟议的工作旨在提供来自中新世木质有机质的定量信息，显示地球的碳循环如何响应冰川驱动的全球海平面变化和随之而来的大陆气候变化。除了测试从深海沉积物推断的碳循环和海平面变化之间的同步性外，拟议的工作还将测试这一新方法的应用范围，并提供数据，以便进一步调查陆地环境变化和海洋环境变化之间的联系。

The Early/Middle Miocene, 24-14 million years ago, represents an important phase in the development of the present 'ice house' world. Specifically the Earth's climate system oscillated between relatively cool and relatively warm states until Antarctic glaciation was firmly established in the later half of the Middle Miocene. On the basis of geochemical data obtained from deep ocean sediments, these climatic oscillations were characterized by sea-level changes and changes in patterns of carbon burial that acted in concert, with inferred increases in carbon burial during sea-level lowstands. Drilling to take place in Miocene shallow marine sediments (IODP Expedition 313) gives an opportunity to assess whether the evidence from the oceanic record is borne out by analysis of these nearshore sedimentary successions, which would be expected (on this old stable continental margin) to respond very sensitively to changes in global sea-level. Recent work on older geological intervals has demonstrated the potential of terrestrial organic matter as an archive of the carbon-isotope composition of atmospheric carbon-dioxide, which acts as a monitor of burial and release of carbon from sedimentary reservoirs. The proposed work is aimed at providing quantitative information from Miocene woody organic matter showing how the Earth's carbon cycle responded to glacially driven changes in global sea level and attendant changes in continental climate. In addition to testing the synchrony between carbon cycle and sea-level changes inferred from deep oceanic sediments, the proposed work will test the limits of application of this new method, and provide data that will allow further investigation of the linkages between environmental changes on land and those occurring in the oceans.