Seismic Attenuation at High Frequencies in Southern California from Coda Waves Recorded at Depth at Cajon Pass, California

南加州高频地震衰减来自加利福尼亚州卡洪山口深度记录的尾波

• 批准号: 9418754
• 负责人: Rachel Abercrombie
• 金额: $ 4.3万
• 依托单位: University of Southern California
• 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 1996-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9418754&HistoricalAwards=false
• 关键词: Seismic; Attenuation; Frequencies; Southern; California

9418754 Abercrombie This research is to investigate both the depth and frequency dependence of both scattering and intrinsic seismic attenuation using seismic data recorded at the Cajon Pass borehole. Most of the previous studies separating scattering from intrinsic attenuation assumed that they are constant throughout the half space. However, recent work indicates that at least Qs is about 100 times higher at 2.5 km depth than surface studies have predicted. Effects on coda waves of a low Q layer at the surface and also depth variations of attenuation associated with the brittle-ductile transition will be investigated. The results will apply to studies of variations of Q before earthquakes and to path corrections used in earthquake source studies. This research is a component of the National Earthquake Hazard Reduction Program. *** ??

小行星9418754 这项研究是调查的深度和频率依赖性的散射和固有的地震衰减使用地震数据记录在Cajon通行证钻孔。 以前的大多数研究将散射与固有衰减分开，假设它们在整个半空间中是恒定的。 然而，最近的研究表明，在2.5公里深度处，Qs至少比表面研究预测的高出约100倍。 将研究表面低Q层对尾波的影响，以及与脆韧性转变相关的衰减深度变化。 其结果可应用于震前Q值变化的研究和震源研究中的路径校正。 这项研究是国家地震减灾计划的一个组成部分。 *** ??