High-Resolution Seismic Imaging: A Comprehensive Application of Waveform Cross-Correlation to Volcanic Fields

高分辨率地震成像：波形互相关在火山场中的综合应用

• 批准号: 1045856
• 负责人: Guoqing Lin
• 金额: $ 27.77万
• 依托单位: University of Miami
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-01-15 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1045856&HistoricalAwards=false
• 关键词: Resolution; Seismic; Imaging; Comprehensive; Application

The proposed research will provide a potential to study the geothermal and hydrothermal features related to volcanic activities and to monitor volcanic activity in the future. The in situ Vp/Vs method will provide a new and robust complement to the existing seismic techniques for mapping Poisson?s ratio. The higher precision of results and the simplicity compared with other techniques will make Vp/Vs ratio a more powerful tool in seismology and will help to track movement of magma and volatiles within a volcano and to estimate spatial variations in fracturing and fluid content in active fault zones.Volcanoes are a natural hazard that produces many kinds of destructive phenomena, such as lava flows, debris avalanches, noxious gas emissions, and airborne ash clouds. With the development of areas near volcanoes, more people and property are at risk of volcanic activity. In order to improve our understanding of eruption process and volcano-earthquake interactions to reduce life and property loss, we need improved data quality and more robust estimation methods to study volcanic systems. Here we propose to pursue a comprehensive application of waveform cross-correlation to several volcanic fields to assess fine-scale near-source spatial and temporal volcanic structural variations. The main five studies that will be applied to the proposed project are: (1) waveform cross-correlation to obtain both compressional and shear wave differential times, (2) composite event method to reduce the random picking error and maximize possible number of observations for each event in seismic tomographic inversions, (3) three- and four-dimensional seismic tomography using first-arrival absolute and differential times, (4) similar event cluster analysis and cross-correlation relocation, and (5) estimate of high-resolution in situ Poisson?s ratio using waveform data.The proposed work will be applied to several volcanic fields, including the Long Valley Caldera, the Coso Geothermal Area, and the Yellowstone. Fine-scale tomographic velocity structure can be used to image the entire volcanic systems and to resolve conduits and magma chambers. High-resolution Poisson?s ratios will be helpful to track magma moving and investigate the possibility of future eruption hazards and high-precision earthquake relocations are also essential for mapping magma migration. These studies are all useful for future real-time analysis of seismic data in volcanic systems and for investigating the history and current states of volcanoes and calderas.

拟议的研究将为研究与火山活动相关的地热和热液特征的潜力，并在未来监测火山活动。原位副总裁/VS方法将为现有的地震技术提供绘制泊松比率的新型地震技术。 The higher precision of results and the simplicity compared with other techniques will make Vp/Vs ratio a more powerful tool in seismology and will help to track movement of magma and volatiles within a volcano and to estimate spatial variations in fracturing and fluid content in active fault zones.Volcanoes are a natural hazard that produces many kinds of destructive phenomena, such as lava flows, debris avalanches,有害的气体排放和空气中的灰云。随着火山附近地区的发展，更多的人和财产有火山活动的风险。为了提高我们对喷发过程和火山 - 地质相互作用以减少生命和财产损失的理解，我们需要改进数据质量和更强大的估计方法来研究火山系统。在这里，我们建议在几个火山场上全面应用波形互相关，以评估近乎源的空间和颞型火山结构变化。 The main five studies that will be applied to the proposed project are: (1) waveform cross-correlation to obtain both compressional and shear wave differential times, (2) composite event method to reduce the random picking error and maximize possible number of observations for each event in seismic tomographic inversions, (3) three- and four-dimensional seismic tomography using first-arrival absolute and differential times, (4) similar event cluster analysis and互相关的重定位和（5）使用波形数据估算了高分辨率原位泊松比的估计。拟议的工作将应用于几个火山场，包括Long Valley Caldera，Coso地热区和黄石。高尺度层析成像速度结构可用于成像整个火山系统并解决导管和岩浆腔室。高分辨率泊松的比率将有助于跟踪岩浆移动，并研究未来喷发危害的可能性和高精度地震重新搬迁对于映射岩浆迁移也至关重要。这些研究对于火山系统中的地震数据的未来实时分析以及研究火山和火山口的历史和当前状态都有用。