Probabilistic Seismic Hazard Analysis Using the New Correlation Relationships for Magnitude Scales

Behrooz Alizadeh,Saeid Pourzeynali

doi:10.28991/cej-0309140

Behrooz Alizadeh, Saeid Pourzeynali

Open Access

https://doi.org/10.28991/cej-0309140

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Abstract

Amol is one of the oldest cities located in north of Iran, Mazandaran province, and its history dates back to the pre-Islamic period. Amol is a city with an area about 3000 square kilometers, a population exceeding 370,000, and includes the old and famous neighborhoods that have a religious, commercial, and service with a long history background. Considering the importance of buildings constructed in this city and the need for their preservation and restoration on one hand, and the occurrence of many severe earthquakes in the past centuries, as well as the recent earthquakes of the last century, on the other hand, encourage us to study the seismicity of this city. Therefore, in this paper, by considering the historical and instrumental earthquakes recorded within a radius of 150 km around this city and the seismic mechanism of the faults located in this region, probabilistic seismic hazard analysis of the area is studied. Then, using the probabilistic relations of the seismic hazard analysis of the Kijko 2000 computer program, the seismicity parameters and the return periods of the earthquake magnitudes are obtained for the area, and at the end, the horizontal peak ground acceleration is zoned for this city.

Highlights

Probabilistic seismic hazard analysis (PSHA) method was first introduced by Cornell [1] in 1968
The seismic sources can be selected within a radius of 100 to 300 km around the site based on the importance of existing structures
Known primary Gutenberg-Richter relationship [7]. This relationship includes two basic parameters known as the “seismicity parameters”. This relationship alone is not sufficient for seismic hazard assessment, because it does not consider any limits for earthquake magnitude and may take large numbers, while the earthquake magnitude varies between some limited ranges

Summary

Introduction

Probabilistic seismic hazard analysis (PSHA) method was first introduced by Cornell [1] in 1968. It should be noted that in none of the above mentioned studies for Iran, nothing is illustrated about the selection of magnitude threshold level of earthquakes and the resulting error in seismic hazard analysis Another important issue in this subject relates to the relationships needed to inter-convert different earthquake-magnitude scales. The main objective of this paper is to evaluate the peak ground acceleration coefficient (defined in Iranian standard No 2800 [32] to calculate the base shear force due to earthquake) using probabilistic seismic hazard analysis, PSHA, for Amol area For this purpose, at the first, the latest status of the major faults in the area; the reported historical earthquakes; and the registered instrumental earthquakes up to the 2017 A.D. within a radius of 150 km from the center of the city have been collected and studied. The zoning map of the horizontal peak ground acceleration coefficient for Amol city and its suburbs have been obtained by using Seisrisk III hazard analysis software

Iran Area

Background seismicity

Earthquakes Catalog

Seismicity Parameters of Amol Zone

Zoning of Horizontal Peak Ground Acceleration for Amol Area

Conclusion