Investigations of Hydrothermal Activity on the Gorda Ridge using ALVIN

作为热液研究的继续， 活动的沉积物覆盖的山脊轴开始在海湾 加州（瓜伊马斯盆地），提供潜水支持 在东北太平洋的戈尔达山脊探险。 的 这个缓慢扩张的山脊的南端（埃斯卡诺巴海槽;半 速率（12毫米/年）被埋在几百米的地下， 浊积岩沉积物来自山区海岸的 太平洋西北部。 沉积物成分，未成熟砂， 变质和花岗岩的起源，形成鲜明对比， 在瓜伊马斯发现的安山岩和生物碎屑的混合物。 因此，热液系统是一个极端的端元， 三种成分：海水、拉斑玄武岩、浊积岩， 结果，沉积物对化学的贡献 热液流体将很容易辨别。 这是特别 这是真的，因为缺乏沉积物的海岭北方部分， 也可供研究。 在对这两个问题的比较研究中， 系统，将有可能建立有效性， 与纯碎屑沉积物的反应， 控制其化学性质。

As a continuation of the investigations of hydrothermal activity on sediment covered ridge axes begun in the Gulf of California (Guaymas Basin), support is provided for a diving expedition to the Gorda Ridge in the Northeast Pacific. The southern end of this slow spreading ridge (Escanaba Trough; half- rate (12 mm/yr) is buried under several hundred meters of turbidite sediments derived from the mountainous coasts of the Pacific Northwest. The sediment composition, immature sands of metamorphic and granitic origin, contrasts sharply with the mixture of andesitic and biogenic debris encountered in Guaymas. The hydrothermal system is thus an extreme end-member with only three components: seawater, tholeiites, turbidites and as a result, the contribution of the sediment to the chemistry of the hydrothermal fluids will be easy to discern. This is especially true since the sediment- starved northern part of the Ridge is also available for study. In a comparative study of these two systems it will be possible to establish the effectiveness of reactions with purely detrital sediments in localizing ore deposits and in controlling their chemistry.//