Love and Rayleigh phase-velocity maps, 5-40 s, of the western and central USA from USArray data
Love and Rayleigh phase-velocity maps, 5-40 s, of the western and central USA from USArray data
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DOI：
10.1016/j.epsl.2013.11.022
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发表时间：
2014-09-15
影响因子：
5.3
通讯作者：
Ekstroem, G.
中科院分区：
文献类型：
--
作者：
Ekstroem, G.
利用2006年至2012年在美国西部和中部运营的1600多个美国阵列地震台站记录的连续数据，使用噪声相关技术绘制了短周期(S 5-40)乐夫波和瑞雷波的相速度图。对间隔小于600公里的所有台对的垂直和横向记录在4小时长的区段中进行交叉相关，并将得到的频谱叠加到台站运行的时间段中。色散曲线是用基于Aki(1957)的方法由相关谱实部中零点的位置确定的。通过相速度测量的反演，估计了在0.25×0.25像素网格上展开的相速度图。与地壳模型CRUST2.0和地幔模型ND08预测的相速度图相比，在较长的周期内有较好的一致性。短周期图上的强慢异常(>；25%)在地理上与盆地和厚沉积盖层区域相关。现有的地壳速度模型不能很好地预测这些异常的强度。(C)2013爱思唯尔B.V.保留所有权利。
Continuous data recorded on more than 1600 USArray seismic stations operating in the western and central US between 2006 and 2012 are used to map phase velocities of Love and Rayleigh waves at short periods (5-40 s) using a noise-correlation technique. Vertical and transverse records for all station pairs separated by less than 600 km are cross correlated in 4-h-long segments, and the resulting spectra are stacked for the time period of station operation. Dispersion curves are determined from the locations of zeros in the real component of the correlation spectra using a method based on that of Aki (1957). Phase-velocity maps expanded on a 0.25 -by-0.25 pixel grid are estimated by inversion of the phase-velocity measurements. Comparison with predicted phase-velocity maps based on the crustal model CRUST2.0 combined with the mantle model ND08 shows good agreement at the longer periods. Strong slow anomalies (>25%) in the short-period maps are geographically correlated with basins and regions of thick sedimentary cover. The strength of these anomalies is not well predicted by existing crustal-velocity models. (C) 2013 Elsevier B.V. All rights reserved.