Estimation of scattering and intrinsic attenuation based on multiple lapse time window analysis in Sikkim Himalayan region, India

2018 ◽  
Vol 284 ◽  
pp. 1-9 ◽  
Author(s):  
Sushil Kumar ◽  
Priyamvada Singh ◽  
Pitam Singh ◽  
Chandra Shekhar
Keyword(s):  
Time Window ◽  
Himalayan Region ◽  
Lapse Time ◽  
Intrinsic Attenuation ◽  
Window Analysis

Intrinsic and Scattering Attenuations in the Crust of the Racha Region, Georgia

2019 ◽  
Vol 14 (02) ◽  
pp. 2050006
Author(s):  
Ia Shengelia ◽  
Nato Jorjiashvili ◽  
Tea Godoladze ◽  
Zurab Javakhishvili ◽  
Nino Tumanova
Keyword(s):  
Time Window ◽  
Frequency Range ◽  
Quality Factors ◽  
Lapse Time ◽  
Intrinsic Attenuation ◽  
Total Attenuation ◽  
Relative Contribution ◽  
Normalization Methods ◽  
Coda Normalization ◽  
Back Scattering

Three hundred and thirty-five local earthquakes were processed and the attenuation properties of the crust in the Racha region were investigated using the records of seven seismic stations. We have estimated the quality factors of coda waves ([Formula: see text]) and the direct [Formula: see text] waves ([Formula: see text]) by the single back scattering model and the coda normalization methods, respectively. The Wennerberg’s method has been used to estimate relative contribution of intrinsic ([Formula: see text]) and scattering ([Formula: see text]) attenuations in the total attenuation. We have found that [Formula: see text] and [Formula: see text] parameters are frequency-dependent in the frequency range of 1.5–24[Formula: see text]Hz. [Formula: see text] values increase both with respect to lapse time window from 20[Formula: see text]s to 60[Formula: see text]s and frequency. [Formula: see text] and [Formula: see text] parameters are nearly similar for all frequency bands, but are smaller than [Formula: see text]. The obtained results show that the intrinsic attenuation has more significant effect than scattering attenuation in the total attenuation. The increase of [Formula: see text] with lapse time shows that the lithosphere becomes more homogeneous with depth.

scholarly journals Multiple Lapse Time Window Analysis using Focal Mechanism

2012 ◽  
Vol 15 (2) ◽  
pp. 85-91 ◽  
Author(s):  
Tae-Woong Chung ◽  
Kazuo Yoshimoto
Keyword(s):  
Focal Mechanism ◽  
Time Window ◽  
Lapse Time ◽  
Window Analysis

MathLTWA: Multiple lapse time window analysis using Wolfram Mathematica 7

2010 ◽  
Vol 36 (10) ◽  
pp. 1388-1392 ◽  
Author(s):  
Edoardo Del Pezzo ◽  
Francesca Bianco
Keyword(s):  
Time Window ◽  
Lapse Time ◽  
Window Analysis ◽  
Wolfram Mathematica

scholarly journals Temporal variation in scattering and intrinsic attenuation due to earthquakes in East Asia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Muhammad Zafar Iqbal ◽  
Tae Woong Chung ◽  
Myung Jin Nam ◽  
Kazuo Yoshimoto
Keyword(s):  
Time Window ◽  
Low Frequency ◽  
Lapse Time ◽  
Ground Acceleration ◽  
Kumamoto Earthquake ◽  
Intrinsic Attenuation ◽  
Before And After ◽  
Gyeongju Earthquake ◽  
Seismic Deformation ◽  
Attenuation Values

AbstractSeparated attenuation values have not been used in post-seismic variation research, although the scattering attenuation (Qs−1) parameter that can be used to estimate crustal inhomogeneity due to cracks. In this study, three earthquakes that occurred in Kumamoto (M7.3), Tottori (M6.6), and Gyeongju (M5.8) in 2016 were investigated by applying a multiple lapse time window analysis to seismograms recorded before and after the events. At a low frequency, significantly greater variation of the Qs−1 value was observed than the intrinsic attenuation (Qi−1) for the Kumamoto earthquake, whereas similarly large variation was observed for the Gyeongju earthquake. For the surrounding Kumamoto earthquake area of increased attenuation, even higher decreases in Qs–1 and Qi–1 were also observed. The increases occurred within a two year-period after mainshock. The large increases in attenuation, corresponding to regions with high peak ground acceleration, were limited to the basin area with an elevation below 500 m. Furthermore, post-seismic increases in attenuation values were found to correlate with the magnitude and length of the quiet periods of the earthquakes. From this study, Qs–1 and Qi–1 were shown as new parameters that can quantitatively measure the post-seismic deformation due to crustal earthquake.

Sign in / Sign up

Export Citation Format

Share Document