Collaborative Research: Mantle Structure and Dynamics of the Ross Sea from a Passive Seismic Deployment on the Ross Ice Shelf

合作研究：罗斯冰架上被动地震部署的罗斯海地幔结构和动力学

• 批准号: 1142518
• 负责人: Douglas Wiens
• 金额: $ 37.42万
• 依托单位: Washington University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1142518&HistoricalAwards=false
• 关键词: Collaborative; Research; Mantle; Structure; Dynamics

Intellectual Merit: The PIs propose to establish an ice shelf network of 18 broadband seismographs deployed for two years to obtain high-resolution, mantle-scale images of Earth structure underlying the Ross Sea Embayment. Prior marine geophysical work provides good crustal velocity models for the region seaward of the ice shelf but mantle structure is constrained by only low-resolution images due to the lack of prior seismic deployments. The proposed stations would be established between Ross Island and Marie Byrd Land. These stations would fill a major geological gap within this extensional continental province and would link data sets collected in the Transantarctic Mountain transition/Plateau region (TAMSEIS) and in West Antarctica (POLENET) to improve resolution of mantle features beneath Antarctica. The proposed deployment would allow the PIs to collect seismic data without the expense, logistical complexity, and iceberg hazards associated with ocean bottom seismograph deployments. Tomographic models developed from the proposed data will be used to choose between competing models for the dynamics of the Ross Sea. In particular, the PIs will investigate whether a broad region of hot mantle, including the Eastern Ross Sea, indicates distributed recent tectonic activity, which would call into question models proposing that Eastern Ross extension ceased during the Mesozoic. These data will also allow the PIs to investigate the deeper earth structure to evaluate the possible role of mantle plumes and/or small-scale convection in driving regional volcanism and tectonism across the region.Broader impacts: Data from this deployment will be of broad interdisciplinary use. This project will support three graduate and two undergraduate students. At least one student will be an underrepresented minority student. The PIs will interact with the media and include K-12 educators in their fieldwork.

智力优势：私人投资机构建议建立一个由18台宽带地震仪组成的冰架网络，部署两年，以获得罗斯海海湾下面地球结构的高分辨率、地幔尺度的图像。以前的海洋地球物理工作为冰架向海区域提供了良好的地壳速度模型，但由于缺乏先前的地震部署，地幔结构仅受低分辨率图像的限制。拟议中的车站将在罗斯岛和玛丽·伯德兰之间建立。这些站将填补这一延伸的大陆省内的一个主要地质空白，并将连接在横贯北极山脉过渡/高原地区(TAMSEIS)和西南极(POLENET)收集的数据集，以提高南极洲下方地幔特征的分辨率。拟议的部署将允许PI收集地震数据，而不会产生与海底地震仪部署相关的费用、后勤复杂性和冰山风险。根据提议的数据开发的层析模型将用于在罗斯海动态的竞争模型中进行选择。特别是，PI将调查包括东罗斯海在内的一大片地热地幔是否表明最近的构造活动是分布的，这将对提出东罗斯伸展在中生代停止的模型提出质疑。这些数据还将使私人投资机构能够调查地球更深处的结构，以评估地幔热柱和/或小规模对流在驱动整个区域的区域火山活动和构造活动方面可能发挥的作用。该项目将资助三名研究生和两名本科生。至少有一名学生将是代表不足的少数族裔学生。PI将与媒体互动，并在他们的实地工作中包括K-12教育工作者。