Fluid flow and authigenic carbonates from southern Hydrate Ridge: Analysis of ODP Leg 204 samples

在卡斯卡迪亚大陆边缘第二增生脊上，天然气水合物影响着地球化学、生物、海洋、地质和构造等多种过程。该脊被称为水合物脊，其特征是高度动态的天然气水合物形成和解离。由于天然气水合物在地质时间尺度上不稳定，伴生碳酸盐可以作为以前天然气水合物赋存的代表。特别是在水合物脊上，已经描述了天然气水合物碳酸盐或笼石。为了追踪天然气水合物的形成及其随时间的成岩变化，我们计划对自生碳酸盐进行地球化学、同位素和沉积学调查，这些研究将在ODP第204阶段进行。

On the second accretionary ridge of the Cascadia continental margin gas hydrates influence many processes including geochemical, biological, oceanographic, geological and tectonic processes. The ridge, known as Hydrate Ridge is characterized by highly dynamic gas hydrate formation and dissociation. Since gas hydrates are not stable over geological time scales, associated carbonates may be used as a proxy for former gas hydrate occurrences. Particularly on Hydrate Ridge, gas hydrate carbonates or clathrites have been described. In order to trace the formation of gas hydrates and their diagenetic changes during time we are planning to conduct geochemical, isotopic and sedimentological investigations on authigenic carbonates which will be drilled during ODP Leg 204.