The Source Characteristics of the Mw6.4, 2016 Meinong Taiwan Earthquake from Teleseismic Data Using the Hybrid Homomorphic Deconvolution Method

Abstract

The kinematic source rupture process of the 2016 Meinong earthquake (Mw = 6.4) in Taiwan was derived from apparent source time functions retrieved from teleseismic S-waves by using a refined homomorphic deconvolution method. The total duration of the rupture process was approximately 15 s, and one slip-concentrated area can be represented as the source model based on images representing static slip distribution. The rupture process began in a down-dip direction from the fault toward Tainan City, strongly suggesting that the rupture had a unilateral northwestern direction. The asperity with an area of approximately 15 × 15 km2 and the maximum slip of approximately 2 m were centered 12.8 km northwest of the hypocenter. Coseismic vertical deformation was calculated based on the source model. Compared with the results derived from InSAR (Interferometric Synthetic Aperture Radar) data, our results demonstrated that the location with maximum uplift was accurately well detected, but our maximum value was just approximately 0.4 times of the InSAR-derived value. It reveals that there are the other mechanisms to affect the vertical deformation, rather than only depending on the source model. At different depths, areas west, east, and north of the hypocenter maintained high values of Coulomb stress changes. This explains the mechanism behind aftershocks being triggered and provides a reference for predicting aftershock locations after a large earthquake. The estimated seismic spectral intensities, including spectral acceleration and velocity intensity (SIa and SIv), were derived. Source directivity effects caused damage to buildings, and we concluded that all damaged buildings were located within a SIa value of 400 gal. Destroyed buildings taller than seven floors were located in an area with a SIv value of 30 cm/s. These observations agree with those on damages caused by the 2010 Jiasian earthquake (ML 6.4) in Tainan, Taiwan.

Correlations between Ground Motion Parameters Measures and Structural Damages of the Mw6.4, 2016 Meinong Taiwan Earthquake Using Hybrid Simulation Method

“…The locations of three stations are shown in Figure 1. Based on the inverted source model of the Meinong earthquake [5] in Figure 2 and the layered model (table 1 [20]), the entire synthetic waveforms are calculated by the hybrid method. The synthetic results with observed recordings (EW component) are demonstrated in Figure 3.…”

“…Liao, et al [4] employed a seismic spectral intensities system (SIs) to evaluate the damages of buildings with different heights for a potential earthquake in central Taiwan. Based on the excellent effects of SIs, a good correlation between the damages to the buildings caused by the 2016 Meinong earthquake and SIs was observed in [5]. Considering the energy with the significant duration of a strong motion, Danciu and Tselentis [6] thought that the characteristic intensity was an outstanding index that can correlate the structural damages of buildings due to maximum deformation energy with the destructiveness of an earthquake well.…”

“…Establishing the intensity parameters thresholds corresponding to damages and mitigating the earthquake disasters in the future are significant works, especially in earthquake-prone areas. In this study, firstly the hybrid simulation method which combines the low-frequency components (f ≦ 1Hz) by theoretical simulation and high-frequency components (1Hz<f ≦ 20Hz) by the semi-empirical technique are used to simulate the recordings around Tainan city according to the source model of 2016 Meinong earthquake [5]. Secondly, the three parameters Ic, CAVstd, and MIV are calculated by the simulated recordings to correlate with the observed damages in the 2016 Meinong earthquake and compared with the previous studies.…”

Multiple parameter analysis for assessing and forecasting earthquake hazards in the Lake Van region, Turkey

“…The Coulomb stress changes from -0.1 to 0.1 (bar) are considered to record the forthcoming earthquake hazards (Yadav et al 2012). The positive Coulomb stress variation shows the loading of stress, pushing the fault towards brittle failure, whilst negative changes in the Coulomb stress distribution correspond to the unloading stress, inhibiting the rupture of the earthquake (Stein et al 1994;Liao et al 2022).…”