Collaborative Research: Geochemical Consequences of Extensive Gas Hydrate Formation in Sediments of the Cascadia Accfetionaly Prism

9731157托雷斯为了量化从卡斯卡迪亚边缘水合物油田到上覆水柱的流体和溶解成分的交换，设计了一个多调查员计划，以测量卡斯卡迪亚地区内各种条件下的这种交换。一项为期两年的现场计划将部署对液体排放进行采样的海底设备。重力、推力和多岩心将被用来评估大陆边缘沉积物中混合的CH4-H2S水合物的近地表形成和分解如何影响海底通量和早期成岩反应。第一年收集的数据将用于评估水合物场组分释放的空间变化，这种变化可能在活跃的喷口地点最显著。这些结果将1)确定在随后两次访问该地区期间进行时间变异性研究的理想地点，2)确定以下实地计划中部署的时间长度和数量。卡斯卡迪亚边缘存在的不同环境，加上时空实验设计，将能够评估卡斯卡迪亚边缘广泛形成的水合物对海底元素迁移、运输和释放的影响。这一知识在全球范围内适用于更广泛的问题，因为水合物地球化学在全球碳预算、气候变化模型、沉积物坡度稳定性和能源问题上具有重大相关性。

9731157 Torres To quantify the exchange of fluids and dissolved constituents from the Cascadia margin hydrate field to the overlying water column a multi-investigator program is designed to measure this exchange under a variety of conditions within the Cascadia region. A 2-year field program will deploy benthic devices that sample fluid discharge. Gravity, push and multicores will be used to assess how near-surface formation and decomposition of a mixed CH4-H2S hydrate in continental margin sediments influences benthic fluxes and early diagenetic reactions. The data collected during the first year will be used to assess the spatial variations of constituent release from the hydrate field, variations that are likely to be most significant at active venting sites. These results will 1) identify ideal sites for temporal variability studies to be conducted during two subsequent visits to the area, and 2) define the length and number of deployments in the following field programs. The different environments present in the Cascadia margin, along with the spatial-temporal experimental design will enable assessment of the effect of widespread hydrate formation in the Cascadia margin on element mobilization, transport, and release at the seafloor. This knowledge has applications for broader issues on a global scale, as hydrate geochemistry is of significant relevance in global carbon budgets, climate change models, sediment slope stability, and energy resource issues.