Collaborative Research: Bridging the gap between long- and short- wavelength structure in the mantle

合作研究：弥合地幔长波长和短波长结构之间的差距

• 批准号: 1015172
• 负责人: Jeroen Ritsema
• 金额: $ 20.92万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1015172&HistoricalAwards=false
• 关键词: Collaborative; Research; Bridging; gap; between

Images of the Earth?s interior are primarily produced by two types of techniques providing snapshots of the Earth at two end-members of resolution. (1) Tomographic imaging provides a whole-mantle view of Earth?s large-scale ( 2000-5000 km) seismic velocity anomalies; (2) Waveform modeling provides a small-scale (~100-500 km) view for specific geographic locations. Because the scale length of features resolved in these imaging techniques varies by an order of magnitude it remains challenging to reconcile these different pictures into one single model of the Earth?s interior. This project aims to reconcile the disparities observed in these images by: (1) Analyzing new seismic data recorded in North America from Earthscope?s Transportable Array (TA) and FlexArray deployments, ANSS Backbone stations, Canadian National Seismic Network Stations, and recent PASSCAL deployments; (2) Analyzing global- and regional-scale models previously introduced to the community by full waveform modeling techniques using the PSVaxi software. The primary goals are to assess the accuracy of the global and regional scale seismic models, and to decipher how complex structures in the deep mantle at all spatial scales affect broadband seismic waveforms.Seismological modeling of deep mantle structure is crucial in understanding the dynamic processes taking place within the Earth. This project will further develop software that is capable of simulating earthquake motions on the global scale. Ultimately this will aid in elucidating the Earth?s interior structure by comparing the simulated waveforms with the newly recorded data. They will test the validity of previously derived Earth models, assessing how structural features in the deep mantle affect the seismic waveforms. Ultimately, this will provide valuable waveform propagation tools and a rigorous assessment of the accuracy of seismic models and images to the community.

地球内部的图像主要是由两种类型的技术产生的，这些技术在两个末端的分辨率下提供了地球的快照。 （1）层析成像提供了地球大规模（2000-5000 km）地震速度异常的全面视图； （2）波形建模为特定地理位置提供了一个小规模（〜100-500 km）的视图。 由于这些成像技术中解决的特征的比例长度因数量级而变化，因此将这些不同图片调和成地球内部单一模型仍然具有挑战性。 该项目旨在通过以下方式调和这些图像中观察到的差异，（1）分析北美记录的新地震数据，从Earthscope的可运输阵列（TA）和Flexarray部署，ANSS骨干站，加拿大国家地震网站以及最近的Passcal部署； （2）分析以前通过使用PSVAXI软件的全波形建模技术引入社区的全球和区域规模模型。 主要目标是评估全球和区域尺度的地震模型的准确性，并破译所有空间尺度上深层中的复杂结构如何影响宽带地震波形。深层地幔结构的视质模型对于理解地球内发生的动态过程至关重要。 该项目将进一步开发能够在全球范围内模拟地震动作的软件。 最终，这将通过将模拟波形与新记录的数据进行比较，有助于阐明地球的内部结构。 他们将测试先前衍生的地球模型的有效性，并评估深幔中的结构特征如何影响地震波形。 最终，这将为社区提供宝贵的波形传播工具，并对地震模型和图像的准确性进行严格的评估。