Collaborative Research: Hydrothermal Processes on the Gakkel Ridge

合作研究：Gakkel 海脊的热液过程

• 批准号: 0425838
• 负责人: Robert Sohn
• 金额: --
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-15 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0425838&HistoricalAwards=false
• 关键词: Collaborative; Research; Hydrothermal; Processes; Gakkel

This is a collaborative proposal from Principal Investigators from Woods Hole Oceanographic Institution (WHOI) and the University of Texas-Austin. They will study hydrothermal processes on the Gakkel Ridge in the Eastern Arctic Basin. The Gakkel Ridge is a key target for hydrothermal studies because it has distinctive geological characteristics as a result of ultra-slow spreading and it is hydrographically isolated from the world's ocean basins, which have important implications for vent field biological communities. Although thermal and particulate signatures indicative of hydrothermal fluids were found in nearly 80% of the CTD casts from the recent U.S./German Arctic Mid-Ocean Ridge Expedition (AMORE) in 2001, no vent fields have been sampled because the ice cover precludes the use of ROVs and submersibles. The Principal Investigators will solve the technical challenges imposed by the ice pack by utilizing nested surveys with autonomous underwater vehicles (AUVs) to map water column plumes, locate buoyant plume stems, conduct fine-scale micro-bathymetric surveys, and to generate photomosaics of the biological communities. They will use the AUV survey data to identify geological and biological sampling targets, and then use a combination of wireline and semi-autonomous methods to obtain the samples. They will complement and guide the AUV and sampling efforts with a more traditional, comprehensive CTD/hydrocast program to measure key parameters such as methane, hydrogen, and manganese in the overlying hydrothermal plumes. These chemical measurements will provide a first indication of important vent fluid characteristics such as the redox environment and the involvement of ultramafic rocks. Based on the CTD, dredging, and mapping results from the AMORE expedition, the Principal Investigators identified two target areas with contrasting geological characteristics. They have leveraged the funds requested from NSF with a NASA Astrobiology grant recently awarded to WHOI and the University of Maryland's Space Systems Laboratory. NASA's interests lie in technology development for autonomous extra-terrestrial sample return, and the grant provides more than $3M to support the AUV component for the field program as an analogue for future missions to Europa. In this current project, they request funds solely for water column CTD work, wireline sampler development, and sample analyses. Broader Impacts: Hydrothermal circulation is a fundamental physical process within the Earth that gives rise to spectacular deep-sea vent fields hosting exotic, chemosynthetic biological communities. Deep-sea vent fields have provided an exciting, multi-disciplinary field of research since their initial discovery in 1977, and the potential for organic compounds to be abiotically synthesized in deep-sea hydrothermal systems may prove to have profound implications for the origin of life on our planet. This research will extend our knowledge of these systems by characterizing hydrothermal processes on a geologically and hydrographically unique mid-ocean ridge. These topics have broad societal interest, and will bring appropriately packaged aspects of the research to the public through a formal education and outreach component already funded in the NASA Astrobiology grant. These activities will include the development of educational modules by a teacher for the highly acclaimed Dive and Discover website (http://www.divediscover.whoi.edu), followed by their participation in the Gakkel expedition and will bring the cruise activities to middle and high school classrooms and to the general public in near real-time. WHOI and the University of Maryland's Space Systems Lab have obtained a grant from NASA's Astrobiology Science and Technology Experiment +Program (ASTEP) that has provided more than $3M to merge robotics technologies with AUVs to enable autonomous sample collection for future missions to Europa, and to demonstrate the system by performing remote sampling of hydrothermal vents in the Arctic Ocean. The NASA grant will support the AUV component of Arctic Ocean field program.One of the proposed options in the ANS proposal for sample recovery is to use a simple, towed system with real-time data return and shipboard control for triggered sampling. This sampling platform has no thrusters, so it cannot be maneuvered except by moving the ship, but it can operate independently and provides a relatively inexpensive system for high quality imaging and sampling at Arctic deepsea vent fields. The Drop Camera System (DCS) consists of a metal frame that includes a digital camera, lights, a depth sensor, a CTD, and a mechanical sampling device capable of multiple samples. The conceptual idea is to use a combination of a claw-style dredge and a slurp gun that can be lowered for sampling with a set of rotating sampling containers. The entire frame would be connected to the icebreaker using standard 0.68" EMO cable. The DCS will be navigated using a relay transponder near the end of the wire and a long-baseline transponder network that will be deployed on the seafloor at each target site (these transponders will also be used to help navigate the AUV surveys). The software interface will be derived from software that runs the National Deep Submergence Facility towed vehicle Argo and associated platforms. All data is converted to ethernet via ethernet-to-RS232 interface converters and analog controlled circuitry. The camera imagery is available in digital format and will be packeted for telemetry. The ethernet data will be piped up the fiber to the surface via a ethernet fibre converter, where it will be logged, displayed in real-time, and also used to allow for individual sensor parameter control. A similar software and control system has already been developed at WHOI and deployed on the shallow water "Habcam" towed system for biological habitat characterization. After seafloor vent field targets have been identified through a combination of CTD and AUV surveys, the Principal Investigators will use the icebreaker to clear a lead for the DCS deployment. They will plan the deployment so that the icebreaker will drift with the ice pack over the target area. In a typical deployment scenario, the DCS will be towed 5-10 meters above the seabed at slow speeds. High dynamic range imagery will be telemetered in real-time to the icebreaker allowing them to make linear photomosaics of the seafloor, and will have command-control capability to deploy the sampler based on the real time digital imagery.

这是来自伍兹霍尔海洋学机构（WHOI）和德克萨斯大学奥斯汀大学的首席研究人员的合作提议。 他们将研究东北极盆地的Gakkel Ridge上的热液过程。 Gakkel Ridge是水热研究的关键目标，因为它具有超慢的扩散而具有独特的地质特征，并且它与世界海洋盆地的水文分离，这对通风现场生物学群落具有重要意义。尽管在2001年，最近美国/埃格尔曼北极中部山脊探险公司（Amore）发现了近80％的CTD铸件中发现了热水流体的热和颗粒标志，但没有对冰盖进行采样ROV和潜水物。 首席研究人员将通过使用自动水下车辆（AUVS）来绘制水柱羽毛，定位浮力羽流茎来解决冰袋施加的技术挑战。生物社区。他们将使用AUV调查数据来识别地质和生物学采样目标，然后使用有线和半自治方法的组合来获取样品。他们将使用更传统的，更全面的CTD/Hydrocast程序来补充和指导AUV和采样工作，以测量上覆盖的水热羽流中的甲烷，氢和锰等关键参数。这些化学测量结果将提供重要的通风液特性，例如氧化还原环境和超镁铁质岩石的参与。 基于Amore探险队的CTD，挖泥和映射结果，主要研究人员确定了两个具有对比地质特征的目标区域。 他们利用了NSF的资金，并提供了最近授予WHOI和马里兰州太空系统实验室的NASA天体生物学赠款。美国国家航空航天局的利益在于自主事务外样品回报的技术开发，该赠款提供了超过300万美元的资金来支持现场计划的AUV组件，作为对欧罗巴未来任务的模拟。在当前的项目中，他们仅要求资金用于水柱CTD工作，有线采样器开发和样本分析。 更广泛的影响：水热循环是地球内的一个基本物理过程，引起了壮观的深海通风田，托有异国情调的化学合成生物学群落。自1977年最初发现以来，深海通风田提供了一个令人兴奋的多学科研究领域，并且有机化合物在深海热液系统中进行非生物合成的潜力可能证明对生命的起源有深远的影响在我们的星球上。这项研究将通过在地质和水文独特的中山脊上表征热液过程来扩展我们对这些系统的了解。这些主题具有广泛的社会兴趣，并将通过已在NASA Astrobiology赠款中资助的正规教育和外展部分将研究的适当包装方面的方面带给公众。这些活动将包括一位老师为备受赞誉的潜水和发现网站（http://www.divediscover.whoi.edu）开发教育模块，随后他们参加了Gakkel Expedition，并将将巡航活动带到中间和高中教室和公众几乎实时地向公众提供。 哇和马里兰大学的太空系统实验室实验室已从NASA的天体生物学科学与技术实验 +计划（ASTEP）获得了一笔赠款，该计划提供了超过300万美元的机器人技术与AUV合并，以使自动样本收集到Europa和Europa和Europa的未来任务，并通过对北极海洋中的热液通风孔进行远程采样来证明系统。 NASA赠款将支持北极海洋场计划的AUV组成部分。ANS提案中的拟议选项之一是使用一个简单的，拖曳的系统，具有实时数据返回和船上板控制进行触发采样。这个采样平台没有推进器，因此除了移动船只外，不能进行操纵，但是它可以独立运行，并在北极深海通风口领域提供了相对便宜的系统，用于高质量的成像和采样。 Drop摄像头系统（DCS）由金属框架组成，其中包括数码相机，灯光，深度传感器，CTD和能够提供多个样品的机械采样设备。概念上的想法是使用爪式挖泥机和泥浆枪的组合，可以使用一组旋转的采样容器来降低采样。整个框架将使用标准的0.68“ EMO电缆连接到破冰船。DC将使用电线末端附近的继电器应答器进行导航，并在每个目标部位部署在海底上的长 - 粘结器应答器网络（这些发音器还将用于导航AUV调查。和模拟控制的电路。还用于允许单个传感器参数控制。通过CTD和AUV调查的组合确定了海底排气场目标后，首席研究人员将使用破冰船清除DCS部署的铅。他们将计划部署，以使破冰船随着冰袋在目标区域上的流动。在典型的部署情况下，DC将以缓慢的速度拖曳海床上5-10米。高动态范围的图像将实时遥测到破冰船，从而使他们可以制作海底的线性光摩萨，并具有命令控制能力，可以根据实时数字图像部署采样器。