Estimating Slab Earthquake Response Spectra from a 3D Q Model
Estimating Slab Earthquake Response Spectra from a 3D Q Model
复制标题
从 3D Q 模型估计板地震响应谱
DOI：
10.1785/0120030036
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发表时间：
2003
影响因子：
3
通讯作者：
G. McVerry
中科院分区：
文献类型：
--
作者：
D. Eberhart‐Phillips;G. McVerry
非均匀岩石圈响应谱的估计问题可以通过直接计算物理模型的衰减来解决。在俯冲带中，板状地震通过地幔楔的衰减与通过板状地震的衰减不同。本文主要关注的是非常高的损失路径，通过衰减地幔下的火山区的北岛，新西兰，低Q值需要修改的“标准”新西兰工程反应谱模型。
由于缺乏强震数据，无法对深板地震通过高衰减地幔带的路径进行标准回归分析。相反，修改已得到使用的3D频率无关的Q模型，已开发的北岛俯冲带2-20 Hz的当地地震t * 数据。通过将t * 地壳结果校准到标准新西兰模型，可以比较标准模型和3D Q模型之间的振幅。附加的路径平均衰减率系数，CQ，为每个源和站对确定。这导致CQ作为质心深度的函数的简单表达式，用于修改标准模型。
这一修改减少了约2-4的因素，火山区下方的地幔楔路径的模型光谱。这种减少是类似于观察到的反应谱的变化，在低于0.4秒的周期，为160公里深的M w 6.0地震。对于通过浅火山区传播的浅源地震，新模型给出的结果类似于由回归分析得出的火山路径衰减项。
2003年2月24日收到Mandarin pt。
The problem of estimating response spectra for a heterogeneous lithosphere can be addressed by directly computing attenuation from physical models. In a subduction zone, slab earthquakes will have different attenuation through the mantle wedge than the slab. This article is primarily concerned with very high loss paths through the attenuating mantle underlying the volcanic zone of the North Island, New Zealand, where low Q requires modification of the “standard” New Zealand engineering response spectrum model.
A lack of strong-motion data prevents a standard regression analysis for paths from deep slab earthquakes through the highly attenuating mantle zone. Instead, modifications have been derived using a 3D frequency-independent Q model that has been developed for the North Island subduction zone from 2-20 Hz local earthquake t * data. By calibrating the t * crustal results to the standard New Zealand model, amplitudes can be compared between the standard model and the 3D Q model. Additional path-averaged attenuation rate coefficients, CQ , for each source and station pair are determined. This results in simple expressions for CQ as a function of centroid depth, for modifying the standard model.
This modification reduces the model spectra by a factor of approximately 2-4 for mantle wedge paths below the volcanic region. This reduction is similar to the observed variation in response spectra, at periods below 0.4 sec, for a 160-km-deep M w 6.0 earthquake. For shallow earthquakes propagating through the shallow volcanic region, the new model gives results that are similar to a volcanic-path attenuation term derived by regression analysis.
Manuscript received 24 February 2003.
H.264编码器DCT的硬件实现及其评估
DOI：
--
发表时间：
2009
期刊：
影响因子：
--
作者：
Choong Geun Lee;V. G. Moshnyaga and K. Hashimoto;宮田康治
通讯作者：
宮田康治