Collaborative Research: Heat Source and Flux Distributions in the Western Ross Sea Seafloor

合作研究：西罗斯海海底的热源和通量分布

• 批准号: 2217128
• 负责人: Kurt Panter
• 金额: $ 35.97万
• 依托单位: Bowling Green State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-10-01 至 2026-09-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2217128&HistoricalAwards=false
• 关键词: Collaborative; Research; Heat; Source; Flux

Understanding the origins and nature of heat available at the base of the cryosphere is essential in deciphering the extent and residence time of the ice in Antarctica and its oceans. Constraints on parameters that control ice-sheet stability, response of the crust to ice loading and unloading, and the effects of volcanism and heat from Earth’s interior on overlying ice is of broad interest to the global climate change community. The goal of this study is to identify and to document the distribution of heat source and heat flux within the seafloor of the southwestern Ross Sea. Geothermal heat flux is one of the basic parameters that shape and control ice flow, ocean circulation, and ecosystem, connecting with subglacial hydrology and its influence on the ability of the ice sheet to slide and internally deform. Despite the importance, particularly in the Antarctic environments, there have been few investigations made in the Ross Sea on how lithospheric heat flux contributes to cryospheric dynamics over time. The project study site in the western Ross Sea seafloor comprises the Terror Rift, which represents the youngest phase of extension within the West Antarctic Rift System, one of the world’s largest rifts and the only one covered by continental ice sheets. The thinned western Ross Sea lithosphere and Terror Rift encompasses active volcanism that range from 5 million years to present-day, suggesting that Pliocene-Quaternary fault movement and dynamic changes in ice sheet extent and thickness over this period are concurrent with magmatic activities.This project will conduct a shipboard survey of the western Ross Sea seafloor. The datasets to be collected include seafloor heatflow/conductivity measurements, real-time seafloor visualization, water-column hydrothermal signal acquisition, and rock sampling via dredging. Heat flow and direct seafloor observations will provide an unprecedented context for seafloor-ocean interactions, addressing some of the biogeochemical cycles in the water column (e.g., chemical and nutrients contributions to the water column from seafloor volcanism and resultant hydrothermal systems) in constraining Ross Sea ecosystems. The compilation of all the data will enable the testing of hypotheses that magmatic intrusion and volcanism in the western Ross Sea is the primary lithospheric heat source that has influenced the dynamics of the ocean-cryosphere system in this region. Data collected will also allow us to refine current timeseries and geodynamics that drive one of the world’s major continental rift systems. Deliverables from this project will be new geospatial information data, including all the underway geophysics grids of the area, publicly available via NSF funded data repositories. After acquiring geochemistry and geochronology, the remaining rock samples will be archived at the Polar Rock Repository. The project will also train 1 postdoc, 2 graduate students, and at least 3 undergraduate students.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

了解在冰冻圈底部可用的热量的起源和性质对于破译南极及其海洋冰的程度和停留时间至关重要。对控制冰片稳定性的参数的限制，地壳对冰的负荷和卸载的反应以及地球内部的火山和热量对上覆的冰的影响是全球气候变化社区的广泛兴趣。这项研究的目的是识别和记录在罗斯海西南海底内的热源和热通量的分布。地热热通量是塑造和控制冰流，海洋循环和生态系统的基本参数之一，它与亚冰川水文学相连及其对冰盖滑动和内部变形的能力的影响。尽管很重要，尤其是在南极环境中，但在罗斯海，关于岩石圈热通量如何随着时间的推移有助于冰圈动力学的研究很少。西罗斯海海底的项目研究地点建造了恐怖裂谷，这代表了南极裂谷中最年轻的延伸阶段，这是世界上最大的裂谷之一，也是唯一被连续冰盖覆盖的裂谷。稀薄的西部罗斯海岩石圈和恐怖裂谷涵盖了活的火山，范围从500万年到当今，这表明在这一时期，冰盖范围和厚度的上新世 - Quertnary断层运动以及冰片范围和厚度的动态变化与Magmatic活动一致。这将对西部Ross Seafloors Seafloors进行船舶调查。要收集的数据集包括海底热流/电导率测量，实时海底可视化，水上水热信号获取以及通过起草的岩石采样。热流和直接的海底观察将为海底互动提供前所未有的环境，以解决水柱中的某些生物地球化学循环（例如，化学和养分对海底火山位的水柱的贡献，以及限制Ross Sea Ecosossys的水层和产生的水热系统）。所有数据的汇编将能够测试西部罗斯海中的岩浆入侵和火山的假设，是影响该地区海洋 - 晶体系统动力学的主要岩石圈热源。收集到的数据还将使我们能够完善当前的时间表和地球动力学，从而推动世界上主要的连续裂谷系统之一。该项目的可交付成果将是新的地理空间信息数据，包括该地区的所有正在进行的地球物理网格，可通过NSF资助的数据存储库公开获得。在获得地球化学和年代学之后，其余的岩石样品将在极地岩石存储库中存档。该项目还将培训1个博士后，2名研究生和至少3名本科生。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，认为通过评估被认为是宝贵的支持。