Hydrothermal Activity in Bransfield Strait, Antarctica: Sample Analysis and Data Reduction

电话9615259 1995年南夏，来自俄勒冈州州立大学的一个研究小组对布兰斯菲尔德海峡的热液活动进行了一次调查（巡航NBP9507）。 该方法是在水柱中寻找温度、浊度和化学性质的异常类型，这些异常类型已知是大洋中脊环境中热液羽流的指示。 这项工作除了确定中央盆地三个活跃热液区的位置外，还详细描绘了该地区的水文地理。 这是在极地地区首次发现的深海热液区。 还发现了一股烟羽通过欺骗岛沉没的破火山口的入口排入海峡。 对这些发现的后续研究很重要，原因有几个：（1）布兰斯菲尔德与大洋中脊系统分离，裂谷历史相对较短（约4个月）。 因此，虽然布兰斯菲尔德横跨大西洋和太平洋，但海峡中的喷口生物群很可能有一个独特的谱系。 在完成水分析和数据解释之前，不可能对生物群进行取样。 (2)布兰斯菲尔德是一个弧后裂谷系统。 很可能，在这种环境中与排气有关的排气流体和矿物沉积物与迄今为止的任何样品都不同。 最接近的类比可能是冲绳海槽或劳盆地，其中自然金是热液组合的一部分。 (3)就世界气候和地区生产力而言，布兰斯菲尔德处于敏感地位。 初步证据表明，欺骗岛是海峡表层沃茨受热液影响的重要水源。 因此，重要的是要量化这种通量，并评估这种现象的地球化学影响。 (4)布兰斯菲尔德是一个几乎没有扩张的裂谷带，或者说，如果扩张正在发生，它是在最近开始的。 另一方面，有一个明确的构造构造把海峡分成三个不同的盆地。 这种情况使我们有机会研究构造过程对热液循环单元就位的影响。 NBP9507巡航的成功导致了关于布兰斯菲尔德水柱的大量信息，无论是在仪器包收集的数据量还是在用于分析的水样数量方面。 来自布兰斯菲尔德的100多个水样可用于分析总可溶性锰。 该奖项支持研究，以完成这一分析计划，并分析结果。 这些数据将提供关于海峡热液活动性质的资料，这对于了解热液沃茨在区域海洋学中的作用和规划今后的工作将是非常宝贵的。

OPP 9615259 Klinkhammer In the austral summer of 1995 a research team from Oregon State University conducted a survey of hydrothermal activity in the Bransfield Strait (cruise NBP9507). The approach was to search the water column for the types of anomalies in temperature, turbidity, and chemistry that are known to be indicative of hydrothermal plumes in mid-ocean ridge settings. This work produced a detailed picture of the hydrography of this area in addition to locating three active hydrothermal areas in the Central Basin. These are the first deep ocean hydrothermal sites ever discovered in a polar region. A plume being discharged to the Strait through the entrance to the sunken caldera at Deception Island was also discovered. Follow-up research on these discoveries is important for several reasons: (1) Bransfield is isolated from the system of mid-ocean ridges and has a relatively short history of rifting (approximately 4 my). So, while the Bransfield straddles the Atlantic and Pacific, vent biota in the Strait may well have a distinct genealogy. It will not be possible to sample biota until the water analyses and data interpretation are completed. (2) Bransfield is a backarc rift system. It is likely that the vent fluids and mineral deposits associated with venting in this setting are unlike anything sampled so far. The closest analogy is probably the Okinawa Trough or Lau Basin where native gold is part of the hydrothermal assemblage. (3) Bransfield is in a sensitive position as far as world climate and regional productivity. Preliminary evidence suggests that Deception Island is a significant source of hydrothermally affected water to the surface waters of the Strait. Consequently, it as important to quantify this flux and access the biogeochemical impact of this phenomenon. (4) Bransfield is a rift zone which has little spreading or, if spreading is occurring, it began in the recent past. On the other hand there is a definite tectonic fa bric that separates the Strait into three distinct basins. This situation allows an opportunity to study the impact of tectonic processes on the emplacement of hydrothermal circulation cells. The success of the NBP9507 cruise has led to an enormous amount of information on the water column in the Bransfield, both in terms of the amount of data collected by instrument packages and in the number of water samples that were taken for analysis. Over 100 water samples from the Bransfield are available for analysis for total dissolvable manganese. This award supports research to complete this analytical program and to analyze the results. These data will provide information about the nature of hydrothermal activity in the Strait which will be invaluable in understanding the role of hydrothermal waters in regional oceanography and for planning future work.