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：研究所建议建立一个由18个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地球结构的高分辨率地幔尺度图像。以前的海洋地球物理工作提供了良好的地壳速度模型的区域向海的冰架，但地幔结构的限制，只有低分辨率的图像，由于缺乏事先的地震部署。拟议中的站点将建立在罗斯岛和玛丽伯德地之间。这些台站将填补这一伸展大陆区内的一个主要地质空白，并将把在跨南极山脉过渡/高原地区（TAMSEIS）和西南极洲（POLENET）收集的数据集连接起来，以提高对南极洲下地幔特征的分辨率。拟议的部署将允许PI收集地震数据，而无需与海底地震仪部署相关的费用，后勤复杂性和冰山危险。从拟议的数据开发的层析模型将用于选择之间的竞争模型的罗斯海的动态。特别是，PI将调查包括东罗斯海在内的广泛的热地幔区域是否表明最近的构造活动，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PI能够调查更深的地球结构，以评估地幔柱和/或小规模对流在推动区域火山活动和整个区域的构造活动中可能发挥的作用。该项目将支持三名研究生和两名本科生。至少有一名学生将是代表性不足的少数民族学生。PI将与媒体互动，并将K-12教育工作者纳入其实地考察。