Compilation of a Local VS Profile Database and Its Application for Inference of VS30 from Geologic- and Terrain-Based Proxies

Stewart, Jonathan P.; Klimis, Nikolaos; Savvaidis, Alexandros; Theodoulidis, Nikos; Zargli, Elena; Athanasopoulos, George; Pelekis, Panagiotis; Mylonakis, George; Margaris, Basil

doi:10.1785/0120130331

Cited by 79 publications

(46 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Lemoine et al (2012), however, acknowledged the fact that their analysis for stable continental was based on a very limited dataset. Stewart et al (2014) compiled and analyzed a large V S dataset for Greece. They propose a framework for estimating V S30 for sites in Greece based on geology and slope.…”

Section: Developing V S30 Site-conditions Mapsmentioning

confidence: 99%

See 1 more Smart Citation

Developing a Geologically Based VS30 Site‐Condition Model for Portugal: Methodology and Assessment of the Performance of Proxies

Vilanova

Narciso

Carvalho

et al. 2018

Bulletin of the Seismological Society of America

View full text Add to dashboard Cite

The inclusion of site-specific conditions is essential to adequately represent the seismic hazard and the seismic risk for a region. We acquired, gathered and organized a near surface shear-wave velocity database for Portugal, and applied a three-step methodological approach for developing a V S30 site-conditions map using extrapolation based on surface geology. The methodology includes: 1) defining a preliminary set of geologically defined units; 2) calculating the probability distribution of log V S30 for each unit; and 3) merging the units according to the results of statistical tests. The final model comprises three geologically defined units characterized by log V S30 distributions that are statistically significantly different from each other: F1-Igneous, metamorphic and old sedimentary rocks; F2-Neogene and Pleistocene formations; and F3-Holocene formations. The site conditions for F3 unit may be further refined using correlations with topographic slope based on the SRTM3 dataset. We analysed the performance site-conditions models based on correlations with exogenous data (topographic slope and surface geology analogues). The results show that the residual distributions between log V S30 values measured and estimated from those proxies are strongly biased for some geological units, emphasizing the need for acquiring regional V S data.

show abstract

Section: Developing V S30 Site-conditions Mapsmentioning

confidence: 99%

“…Because V S30 is strongly correlated with deeper velocity structures (Boore, 2004;Boore et al, 2011) it has been shown to describe site-effects at ground motion frequencies corresponding to wavelengths much longer than 30 m (Stewart et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

Developing a Geologically Based VS30 Site‐Condition Model for Portugal: Methodology and Assessment of the Performance of Proxies

Vilanova

Narciso

Carvalho

et al. 2018

Bulletin of the Seismological Society of America

View full text Add to dashboard Cite

show abstract

“…Previous studies have identified that the applicability of these approaches to the estimation of V s30 is dependent on the local geologic and topographic environment. A comparative study of the geology-slope approach and the terrain-based approach in Greece showed that both approaches were equally applicable (r lnv = 0.396, r lnv-= 0.394, respectively) (Yong et al 2012;Stewart et al 2014). A hybrid geology-slope approach with additional proxies was found to perform better (lower values of R and r lnv ) than the geology-based approach in the Pacific Northwest of North America (Ahdi et al 2017).…”

Section: Introductionmentioning

confidence: 99%

Methodology and Assessment of Proxy-Based Vs30 Estimation in Sichuan Province, China

Wen

Liu

Guo

et al. 2020

Int J Disaster Risk Sci

View full text Add to dashboard Cite

Although time-averaged shear wave velocity to the depth of 30 m (V s30) is an important indicator of earthquake site effects, it is difficult to obtain. Several proxies have been used either individually or in combination to infer V s30 values during seismic hazard estimation under limited observational conditions. Sichuan Province is an area highly prone to earthquakes. Complex geological structures and lack of drilling sites mean that it is particularly important to establish a suitable approach for the estimation of V s30 values for site classification. This study compared the application of three proxy-based approaches-geology-based, topographic slope-based, and terrain-based-to the estimation of V s30 values in Sichuan Province. The results revealed that the residual between the measured logV s30 values and the estimations derived from the terrain-based approach was smallest, indicating best predictability. Stability analysis of the three approaches also showed that the terrain-based approach performed best. However, its performance in the plain area was poor, that is, the V s30 values were mostly underestimated. This might indicate that the old strata, hard rock, and alluvial deposits formed by Quaternary glacier sediments were not identified appropriately in the plain area, highlighting the need for localized corrections.

show abstract

“…In recent studies for nationwide purposes, Forte et al [22] provided seismic soil classification maps for Italy based on site-specific measurements, including Vs30 measurements and geological information. Stewart et al [23] produced geologic and terrain-based site condition maps for California using geological information and 1, 3, 9 and 30 arcsec DEMs. The results produced by three arcsec datapoints were more accurately relative to the real measurements than other DEMs.…”

Section: Introductionmentioning

confidence: 99%

DEM-Based Vs30 Map and Terrain Surface Classification in Nationwide Scale—A Case Study in Iran

Karimzadeh

Feizizadeh

Matsuoka

2019

IJGI

View full text Add to dashboard Cite

Different methods have been proposed to create seismic site condition maps. Ground-based methods are time-consuming in many places and require a lot of manual work. One method suggests topographic data as a proxy for seismic site condition of large areas. In this study, we mainly focused on the use of an ASTER 1c digital elevation model (DEM) to produce Vs30 maps throughout Iran using a GIS-based regression analysis of Vs30 measurements at 514 seismic stations. These maps were found to be comparable with those that were previously created from SRTM 30c data. The Vs30 results from ASTER 1c estimated the higher velocities better than those from SRTM 30c. In addition, a combination of ASTER 1c and SRTM 30c amplification maps can be useful for the detection of geological and geomorphological units. We also classified the terrain surface of six seismotectonic regions in Iran into 16 classes, considering three important criteria (slope, convexity and texture) to extract more information about the location and morphological characteristics of the stations. The results show that 98% of the stations are situated in six classes, 30% of which are in class 12, 27% in class 6, 17% in class 9, 16% in class 3, 4% in class 3and the rest of the stations are located in other classes.

show abstract

Compilation of a Local VS Profile Database and Its Application for Inference of VS30 from Geologic- and Terrain-Based Proxies

Cited by 79 publications

References 23 publications

Developing a Geologically Based VS30 Site‐Condition Model for Portugal: Methodology and Assessment of the Performance of Proxies

Developing a Geologically Based VS30 Site‐Condition Model for Portugal: Methodology and Assessment of the Performance of Proxies

Methodology and Assessment of Proxy-Based Vs30 Estimation in Sichuan Province, China

DEM-Based Vs30 Map and Terrain Surface Classification in Nationwide Scale—A Case Study in Iran

Contact Info

Product

Resources

About