Collaborative Research: Hydrothermal and Microbiological Investigations of the Active Brothers Volcano in the Kermadec Arc

合作研究：克马德克弧内活跃兄弟火山的热液和微生物研究

• 批准号: 1558795
• 负责人: Anna-Louise Reysenbach
• 金额: $ 11.92万
• 依托单位: Portland State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-03-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1558795&HistoricalAwards=false
• 关键词: Collaborative; Research; Hydrothermal; Microbiological; Investigations

Nearly one third, or 22,000 km of Earth's submarine volcanic activity, occurs along intraoceanic volcanic arcs. The volcanos and seafloor spreading centers in these areas host significant numbers of hydrothermal systems that vent hot, mineral-charged waters into the oceans and support unique micro- and macrobiological communities that are found nowhere else on Earth. The chemistry of hydrothermal systems found along interoceanic arcs differ substantially from those located at mid-ocean ridges, with arc systems exhibiting strong magmatic signatures. This unique chemistry, coupled with the shallow depths at which the calderas of many of these arc volcanoes occur, result in highly acidic and volatile-enriched fluids that are the precursors to economically metal-rich mineral deposits. Because these systems are difficult to detect unless they are come upon by accident, these systems are relatively unstudied and have unexplored microbiological communities. This research will undertake a 20-day oceanographic research expedition and shore-based laboratory studies of the samples that are collected to characterize one of these unique volcanoes: Brothers Volcano in the Kermadec Arc in the Western Pacific Ocean. This volcano has also been selected as a potential ocean drilling site with science focused on the development of a better understanding of active seafloor hydrothermal systems and their circulation pathways. Goals of the present research program include using remotely operated vehicles to survey and sample the rocks, vent fluids, and microbes in the Brothers Volcano caldera. It also includes an extensive heat flow survey to identify areas of fluid recharge and discharge. Broader impacts of the research include establishing collaborations with New Zealand scientists, graduate student training, support of two investigators whose genders are under-represented in the sciences, and public outreach through the Woods Hole Oceanographic Institution's award-winning Dive and Discover website. Presentations will also be made to the public as opportunities present themselves. There is also the potential for the discovery of new microbiological species with unusual metabolic pathways or enzymes which may have natural products and/or pharmacological utility. The work also has the ability to help us understand the formation of hydrothermal vent related sulfide deposits which commonly are rich in copper, gold, and molybdenum. This research also complements the science agenda of the NSF-funded International Ocean Discovery Program and provides a critical site survey upon which seafloor drilling legs can be based. This research is focused on documenting and understanding the geology, heat flow, hydrothermal, and microbial characteristics of the Brothers Volcano edifice in the Kermadec Arc in the Western Pacific Ocean. A 20-day sample collection cruise will take place in the caldera of the Brothers Volcano and will be followed up by onshore laboratory geochemical and microbiological work. The research project will test five hypotheses related to hydrothermal circulation at Brothers volcano. Work will include documenting the heat and chemical fluxes coming from the caldera; the role of low pH in these systems; and the influence of magmatic volatile-rich hydrothermal fluids on rock alteration. Research will also involve determining mechanisms and the extent of fluid-rock interaction and mass transfer of carbon, sulfur, metals and metalloids into the ocean; the subseafloor distribution of metals and associated mineral deposits; and the diversity and extent of microbial life in an arc volcano hydrothermal environment. Brothers volcano is ideally suited for such studies because it harbors two different styles of hydrothermal vents within its caldera: (1) high-temperature black smoker-type fluids discharging from Cu-Au-rich sulfide chimneys; and (2) moderate temperature, gassy, acid-sulfate waters where native sulfur chimneys and extensive Fe-oxyhydroxide crusts occur. During the cruise a mapping, sampling, and observational program will take place, consisting of a series of dives by a remotely operated vehicle to four distinct hydrothermal fields within Brothers caldera. Thermal blankets will be deployed in the caldera around the hydrothermal vents to measure heat flow and fluid recharge and discharge zones. Coexisting minerals and fluids associated with the vents and the surrounding caldera will be collected and geochemically analyzed. This research and the resulting caldera survey complements other observational and analytical work carried out over the past decade by NOAA, the National Ocean and Atmospheric Administration, and its corresponding agency associated with the government of New Zealand. One important goal of the survey work is to identify potential sites for ocean drilling for further understanding of seafloor arc volcanic systems.

地球海底火山活动的近三分之一或22,000公里发生在河内火山弧内。 这些地区的火山和海底扩展中心拥有大量的热液系统，这些系统将热，矿物充电的水排入海洋，并支持独特的微型和巨型生物学群落，这些群落在地球上没有其他地方。沿着跨跨弧线发现的水热系统的化学与位于中山脊的弧形大不相同，弧系统表现出强烈的岩浆特征。 这种独特的化学性质，再加上许多这些弧火山的火山口的浅深度，导致高度酸性和挥发性富含富含经济金属富含矿物质的矿物质的前体。由于这些系统偶然出现，除非它们偶然出现，否则这些系统是相对未研究的，并且具有未开发的微生物群落。这项研究将进行为期20天的海洋学研究探险和基于海岸的实验室研究，以表征这些独特火山之一的样品：西太平洋的克马德克弧的兄弟火山。该火山还被选为潜在的海洋钻井现场，科学的重点是对活性海底热液系统及其循环途径的更好理解。本研究计划的目标包括使用远程操作的车辆来调查和品尝火山火山兄弟火山兄弟的岩石，排气液和微生物。它还包括一项广泛的热流调查，以识别流体充电和排放区域。这项研究的更广泛的影响包括与新西兰科学家建立合作，研究生培训，两名调查人员的支持，他们的性别在科学中的代表性不足，以及通过伍兹霍尔海洋学机构屡获殊荣的潜水和发现网站的公众推广。随着机会出现，也将向公众发表演讲。还具有可能具有天然产物和/或药理学效用的异常代谢途径或酶的新微生物物种的潜力。这项工作还具有帮助我们了解与铜，金和钼相关的水热相关硫化物沉积物的形成。这项研究还补充了由NSF资助的国际海洋发现计划的科学议程，并提供了一项关键的现场调查，可以对其进行海底钻孔腿的基础。这项研究的重点是记录和理解西太平洋克马底弧兄弟火山大厦的地质，热水，水热和微生物特征。一场为期20天的样本收集巡航将在火山兄弟的火山口进行，并将进行陆上实验室地球化学和微生物学工作。该研究项目将检验兄弟火山兄弟的五个与热液循环有关的假设。工作将包括记录来自火山口的热量和化学通量；低pH在这些系统中的作用；以及富含岩浆挥发性的水热流体对岩石改变的影响。研究还将涉及确定机制以及碳，硫，金属和金属体的流体岩石相互作用以及向海洋的质量转移的程度；金属和相关矿藏的子层分布；以及在弧形热液环境中微生物寿命的多样性和程度。兄弟火山非常适合此类研究，因为它在其火山口内拥有两种不同样式的水热通风孔：（1）从富含Cu-Au的富含Cu-Au的硫化物烟囱中排出的高温黑色吸烟者型液体； （2）中等温度，气味，酸硫酸盐水，天然硫烟囱和广泛的富氧氧氧化壳发生。在巡航期间，将进行映射，采样和观察计划，包括一系列远程操作的车辆潜水到Caldera兄弟内的四个不同的热液场。热毯将部署在水热通风口周围的火山口中，以测量热流和液体充电和排放区域。将收集与通风孔和周围火山口相关的矿物质和流体，并通过地球化学分析。这项研究以及由此产生的火山口调查对NOAA，国家海洋和大气管理局及其与新西兰政府相关的相应机构进行了过去十年中的其他观察和分析工作。调查工作的一个重要目标是确定海洋钻井的潜在地点，以进一步了解海底弧火山系统。