Shear wave crustal velocity model of the Western Bohemian Massif from Love wave phase velocity dispersion
Shear wave crustal velocity model of the Western Bohemian Massif from Love wave phase velocity dispersion
复制标题
洛夫波相速度色散的西波希米亚地块剪切波地壳速度模型
DOI：
10.1007/s10950-010-9209-4
复制
发表时间：
2011
影响因子：
1.6
通讯作者：
J. Brokesová
中科院分区：
文献类型：
--
作者：
P. Kolínský;J. Málek;J. Brokesová
我们提出了对捷克共和国（中欧）波希米亚地块不同地质单元的剪切波速度进行新的定量测定。基本拉夫波模式的相速度是沿着穿过研究区域的三个主要地质单元和一个裂谷状结构的两条长剖面（约 200 公里）测量的。我们开发了用于频率-时间分析的经典多重滤波技术的修改版本，并将其应用于两站相速度估计。提供了分析和反演的测试。分析了三场爱琴海地震的地震图。两个轮廓之一进一步分为四个较短的子轮廓。长轮廓产生平滑的色散曲线；而子轮廓的曲线形状复杂。色散曲线波动被解释为由表面波传播的不同后方位角和表面波模式耦合引起的与周期相关的视速度异常。为每个周期找到适当的传播反向方位角，并针对该真实传播方向校正色散曲线。对于地壳的一维剪切波速度模型，长剖面和短剖面的曲线都是反转的。研究发现，所有四个研究的子剖面的地下横波速度约为 2.9 公里/秒。穿过旧摩尔达努比亚单元和泰普拉-巴兰迪亚单元的两个剖面的特征是上地壳中的速度较高，为 3.8 公里/秒，而对于萨克斯图林阶单元，我们发现相同深度的速度略低，约为 3.6 公里/秒。我们获得了摩尔达努比亚单元和特普拉-巴兰迪亚单元中莫霍面上方剪切波低速区的指示。埃格尔裂谷（Teplá-Barrandian-Saxothuringian 单元接触面）的面积与所有其他三个单元显着不同。上地壳速度较低表明裂谷的沉积物和火山充填以及导致地震群的流体活动。下地壳速度较高，加上莫霍面较弱甚至缺失，意味着上地幔正在上扬。
We propose a new quantitative determination of shear wave velocities for distinct geological units in the Bohemian Massif, Czech Republic (Central Europe). The phase velocities of fundamental Love wave modes are measured along two long profiles (~200 km) crossing three major geological units and one rift-like structure of the studied region. We have developed a modified version of the classical multiple filtering technique for the frequency-time analysis and we apply it to two-station phase velocity estimation. Tests of both the analysis and inversion are provided. Seismograms of three Aegean Sea earthquakes are analyzed. One of the two profiles is further divided into four shorter sub-profiles. The long profiles yield smooth dispersion curves; while the curves of the sub-profiles have complicated shapes. Dispersion curve undulations are interpreted as period-dependent apparent velocity anomalies caused both by different backazimuths of surface wave propagation and by surface wave mode coupling. An appropriate backazimuth of propagation is found for each period, and the dispersion curves are corrected for this true propagation direction. Both the curves for the long and short profiles are inverted for a 1D shear wave velocity model of the crust. Subsurface shear wave velocities are found to be around 2.9 km/s for all four studied sub-profiles. Two of the profiles crossing the older Moldanubian and Teplá-Barrandian units are characterized by higher velocities of 3.8 km/s in the upper crust while for the Saxothuringian unit we find the velocity slightly lower, around 3.6 km/s at the same depths. We obtain an indication of a shear wave low velocity zone above Moho in the Moldanubian and Teplá-Barrandian units. The area of the Eger Rift (Teplá-Barrandian–Saxothuringian unit contact) is significantly different from all other three units. Low upper crust velocities suggest sedimentary and volcanic filling of the rift as well as fluid activity causing the earthquake swarms. Higher velocities in the lower crust together with weak or even missing Moho implies the upper mantle updoming.
影响因子：
2.3
作者：
Y. Yoshida;D. Suetsugu
通讯作者：
Y. Yoshida;D. Suetsugu
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