Analysis of Antarctic Broad Band PASSCAL Data for Surface Wave Dispersion

南极宽带PASSCAL面波色散数据分析

• 批准号: 9418114
• 负责人: Arthur Lerner-Lam
• 金额: $ 2.7万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-07-15 至 1997-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9418114&HistoricalAwards=false
• 关键词: Analysis; Antarctic; Broad; Band; PASSCAL

Abstract This award supports a study of the technical feasibility of collecting and analyzing broad-band teleseismic data from the Antarctic continental interior using portable seismometers. The West Antarctic Ice Sheet overlies a region of the Antarctic continent which may be in extension. However, very little is actually known about the seismic structure of the crust and upper mantle. The deployment of portable broad-band seismometers for passive teleseismic studies may offer the most effective means of acquiring data on the deep structure of this continent. Data collected with broad-band PASSCAL seismometers deployed as an augmentation to the ICEQUAKE network in central West Antarctica represents useful records with several well defined teleseismic events (about 10-20 events) that were recorded over a period of five weeks. The data are of sufficient quality to allow the estimation of fundamental mode dispersion curves down to periods as low as 50 seconds, and the analysis of body phases for boundary interactions and travel time anomalies. This should provide first-order constraints on the shear velocity structure of the crust and upper mantle down to a depth of approximately 200 km. Additionally, the data contain sufficient information to develop ambient noise models for ice sheets. Consequently, if successful, this work will lead to important guidance for the technical design elements necessary for developing an important experimental resource for seismic studies that may lead to significant advances in understanding the Antarctic continent.

摘要该奖项支持对使用便携式地震仪从南极大陆室内收集和分析从南极大陆室内收集和分析广泛频段远距离数据的技术可行性的研究。 南极冰盖覆盖了南极大陆的一个区域，可能会延伸。 但是，关于地壳和上地幔的地震结构实际上知之甚少。 用于被动远距离研究的便携式宽带地震仪的部署可能提供了获取有关该大陆深层结构的数据的最有效方法。 用宽带密封地震仪收集的数据被部署为扩大到西南极中部的冰震网络的增强，代表了有用的记录，其中有几个定义明确的伸展事件（约10-20个事件），这些事件在五周内记录了。 数据具有足够的质量，可以估算基本模式分散曲线降低到50秒的时间，并分析边界相互作用和旅行时间异常的身体相分析。 这应该对地壳的剪切速度结构和上地幔的剪切速度结构提供一阶约束，至约200 km的深度。 此外，数据包含足够的信息来开发冰盖的环境噪声模型。 因此，如果成功的话，这项工作将为为地震研究开发重要的实验资源所需的技术设计元素提供重要的指导，这可能会导致理解南极大陆的重大进展。