Hamid Zafarani

Hamid Zafarani
International Institute of Earthquake Engineering and Seismology | iiees · Seismology

Professor

About

96
Publications
21,032
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,091
Citations
Citations since 2017
52 Research Items
776 Citations
2017201820192020202120222023050100150
2017201820192020202120222023050100150
2017201820192020202120222023050100150
2017201820192020202120222023050100150
Introduction
-Site-Specific Seismic Hazard Analysis for critical facilities. -Development and Selection of Ground motion prediction equations for Iran. -Risk and Hazard Analysis for distributed systems. -Time-dependent seismic hazard analysis including statistical and physical approaches. -Deformation models for Iranian plateau, to estimate more accurate fault slip rates. -Development of Iranian national risk-targeted model for seismic and tsunami hazard mapping. -Simulation of earthquake scenarios
Additional affiliations
August 2008 - present
University of Tehran
Position
  • Lecturer
August 2008 - present
University of Tehran
Position
  • Lecturer
January 2008 - present

Publications

Publications (96)
Article
Full-text available
This study aimed at designing triggering thresholds for parametric insurance mechanisms to transfer the subsequent risk of production interruption—caused by an earthquake—to the insurer. The Parsian gas refinery complex located in Zagros, a seismic-prone area in southern Iran, was investigated as a case study. The whole gas refinery system was divi...
Article
Full-text available
The epidemic-type aftershock sequence (ETAS) model provides an effective tool for predicting the spatio-temporal evolution of aftershock clustering in short-term. Based on this model, a fully probabilistic procedure was previously proposed by the first two authors for providing spatio-temporal predictions of aftershock occurrence in a prescribed fo...
Article
An Iranian earthquake database has been employed to propose local empirical equations to predict non-spectral ground motion intensity measures, including Arias intensity, cumulative absolute velocity and duration of ground motions. The significant duration models have been considered 5% – 75% and 5% – 95% of Arias intensity in analyses. The bracket...
Article
Full-text available
Makran subduction zone, along the southern coasts of Iran and Pakistan, has a wide potential seismogenic zone and may be capable of generating large magnitude (M ~ 9) tsunamigenic earthquakes. Considering ambiguities exist in tsunamigenic source characterization for subduction megathrusts like Makran, where detailed geologic, seismic, and geodetic...
Article
On 12 November 2017, an earthquake with a moment magnitude of 7.3 struck the west of Iran near the Iraq border. This event was followed about 9 and 12 months later by two large aftershocks of magnitude 5.9 and 6.3, which together triggered intensive seismic activity known as the 2017-2019 Kermanshah sequence. In this study, we analyze this sequence...
Article
Full-text available
Probabilistic seismic hazard analysis, as the most prevalent approach to evaluate earthquake hazard, is commonly based on earthquake catalogs. Although previous studies show that the recurrence time of large-magnitude (Mw> 7.0) events in Iran is more than ~ 1000–2000 years, the available instrumentally recorded earthquakes are limited to less than...
Preprint
Full-text available
The epidemic-type aftershock sequence (ETAS) model provides an effective tool for predicting the spatio-temporal evolution of aftershock clustering in short-term. Based on this model, a fully probabilistic procedure was previously proposed by the first two authors for providing spatio-temporal predictions of aftershock occurrence in a prescribed fo...
Article
Full-text available
Geodetic and seismological data are crucial for examining the kinematics and active tectonics in structural zones. The current tectonic stress field can be inferred from the focal mechanism stress inversion (FMSI) and the seismic and geodetic strain rates (SSR and GSR). In this study, a reliable focal mechanism solution for earthquakes from 1968 to...
Article
Shallow crustal earthquakes (SCE) occur in different seismotectonic regions of the Iranian plateau. In this study, 10 ground motion prediction equations (GMPEs) developed based on local, regional, and global data from SCE are considered as candidates to test their explanatory power against Iranian strong motion data. To show the applicability of ca...
Preprint
Full-text available
Following a severe disaster, a quick and reliable evaluation of the structural damage state is one of the crucial steps to making decisions and disaster management. Based on a realistic estimate of types and levels of damages, decisions related to the structural performances, repair possibility, or in severe cases, a replacement could be made. In a...
Preprint
Full-text available
Probabilistic seismic hazard analysis, as the most prevalent approach to evaluate earthquake hazard, is commonly based on earthquake catalogs. Although previous studies show that the recurrence time of large-magnitude ( M w > 7.0) events in Iran is more than ~1000-2000 years, the available instrumentally recorded earthquakes are limited to less tha...
Conference Paper
On 12 November of 2017, an earthquake with a moment magnitude of 7.3 struck the west of Iran near the Iraq border. This event was followed about 9 and 12 month later by two large aftershocks of magnitude 5.9 and 6.3, which together triggered a large seismic activity known as the 2017-2019 Kermanshah sequence. In this study, we analyze this sequence...
Article
Full-text available
Aftershock hazard maps contain the essential information for search and rescue process, and re-occupation after a main-shock. Accordingly, the main purposes of this article are to study the aftershock decay parameters and to estimate the expected high-frequency ground motions (i.e., Peak Ground Acceleration (PGA)) for recent large earthquakes in th...
Article
Full-text available
The forecasting of large aftershocks is a preliminary and critical step in seismic hazard analysis and seismic risk management. From a statistical point of view, it relies entirely on the estimation of the properties of aftershock sequences using a set of laws with well-defined parameters. Since the frequentist and Bayesian approaches are common to...
Article
Full-text available
Iranian plateau is considered mostly as a shallow crustal area except the Makran region in south-east Iran in which the subduction events can happen. Due to the tectonic characteristics of the Makran subduction zone, different categories of GMPEs are required for seismic hazard assessment including GMPEs for shallow crustal events and subduction zo...
Article
Spatial correlations of peak ground and pseudo spectral acceleration are estimated as a function of intersite separation distance. More than 2286 three-component records from 461 Iranian earthquakes are employed to evaluate the intra-event residual correlation based on multiple earthquakes, considering both local and regional ground motion predicti...
Article
Full-text available
Earthquakes has been known as a destructive natural disaster. Due to high human casualties and economical losses, earthquake prediction appears critical. The b-value of Gutenberg Richter law has been considered as precursor to earthquake prediction. Temporal variation of b-value before earthquakes equal or greater than Mw = 6.0 has been examined in...
Article
Ideally, hazard assessment for seismic design should quantitatively control the risk of exceeding different limit states (LS) over the structure's lifetime. In fact, the geographical variation of the ground motion hazard curves has an impact on the total seismic risk of code-conforming buildings. This paper examines the path towards a ground motion...
Article
Full-text available
New empirical relations between macroseismic intensity and ground motion parameters including peak ground acceleration and velocity are developed using strong ground motion data and Modified Mercalli Intensity (MMI) information from earthquakes within Iran plateau. The strong motion data consists of 116 three-component waveforms of 23 earthquakes w...
Article
Full-text available
A strong earthquake occurred on November 12, 2017, in Sarpol-e Zahab city, western Iran, with the moment magnitude (Mw) of 7.3 and a focal depth of 18 km. The maximum horizontal peak ground acceleration of 0.69 g was recorded at the Sarpol-e Zahab station. Significant damages were observed in frame and masonry buildings, while the damage distributi...
Article
The Hojedk area in the southeastern Iran experienced three earthquakes during 12 days in December 2017. These events occurred in proximity to a region that has experienced several moderate and large events in the past. In this paper, the role of Coulomb stress changes in occurrence of the Hojedk cluster was investigated, and also the produced stres...
Article
Full-text available
A fully Monte Carlo simulation (MCS) which applies to the across region in each step, allows incorporation spatial correlations in each step conditional on the previous step and each simulation must repeat each several times; therefore, the size of computation is concern. The size of computation can be reduced at each step by developing scenarios....
Conference Paper
Full-text available
Immediate after a large earthquake, accurate prediction of spatial and temporal distribution of aftershocks has a great importance for planning search and rescue activities. Currently, the most sophisticated approach to this goal is probabilistic aftershock hazard assessment (PASHA). Spatial distribution of the aftershocks fallowing moderate to lar...
Article
New intensity prediction equation is evaluated for Iran using isoseismal maps of 31 earthquakes with MW 5.1–7.4 occurred from 1939 to 2017 including 7.3 destructive Sarpol-e Zahab earthquake on 12 November 2017. The results show different distance-dependent intensity attenuation rate in comparison with previous studies for Iran and other regions of...
Article
Ground motion intensity measures and structural responses are correlated in nearby sites. The value of this correlation relies on some parameters such as the local geology and distance between the two sites and the natural period of structures, particularly, when lifeline systems or distributed structures are of concern, the issue becomes more impo...
Article
The 26 December 2003 (Mw 6.6) Bam earthquake is one of the most destructive events in the recorded history of Iran. Good variable-slip fault models and precise aftershock data enabled us to calculate Coulomb stress changes on the surrounding faults, optimally oriented faults, and the aftershock nodal planes to learn whether they were brought closer...
Article
Abstract New intensity prediction equation is evaluated for Iran using isoseismal maps of 31 earthquakes with MW 5.1–7.4 occurred from 1939 to 2017 including 7.3 destructive Sarpol-e Zahab earthquake on 12 November 2017. The obtained intensity prediction equation based on Modified Mercalli Intensity (MMI) scale for intensity range 4 to10 and distan...
Article
Full-text available
The evaluation of potential human and economic losses arising from earthquakes, which may affect urban infrastructures that are spatially extended over an area, is important for nationalauthorities, local municipalities, and the insurance and reinsurance industries. However, seismic-risk analysis of distributed systems and infrastructures need to a...
Article
Full-text available
Southeast of Iran experienced 8 destructive earthquakes during 30 years from 1981 to 2011. Six of these events with M>6.5 were fatal and caused great human and financial losses in the region. The 1981 July 28 (Mw 7.2) Sirch earthquake with 65 km surface rupture was the largest event in this region since 1877 and with other three earthquakes occurre...
Article
Full-text available
Estimation of ground-motion amplitudes of different hazard levels is of paramount importance in planning of urban development of any metropolis. Such estimation can be computed through a probabilistic seismic hazard analysis (PSHA). This paper concentrates on the PSHA of an area located in Shiraz city, southern Iran. The area includes whole of Shir...
Article
By using slip model from USGS and focal mechanism and aftershocks distribution from Iranian Seismological Center (IRSC) for Sarpol-e-Zahab earthquake (Mw 7.3) in the 2017 November 12 we investigated the correlation between Coulomb stress changes and aftershocks distribution. In this study, we selected about 500 aftershocks with magnitude larger tha...
Article
Full-text available
Numerical simulation of dam-foundation-fault system, considering the earthquake source, propagation path and local site effects, was carried out for realistic and reasonable seismic safety analysis of concrete dams. The Domain Reduction Method (DRM) was used for seismic analysis of Dam-Foundation-Fault (DFF) system in which, a modular two-step meth...
Conference Paper
In this study capability of equivalent pulses for estimation of seismic response of an isolated bridge subjected to near fault ground motions is investigated. Several simple pulse models have been already developed to represent near fault pulse-type ground motions. One application of such models is to simulate site-specific earthquake ground motion...
Conference Paper
Iran is one of the most seismically active continental regions in the world and an accurate assessment of earthquake hazard has a significant effect on decreasing earthquake losses and making plans for urban development. In this regard, using novel and alternative approaches in hazard assessment will greatly improve our knowledge and many questions...
Conference Paper
Full-text available
West of Iran experienced a large earthquake in the 2017 November 12 with moment magnitude of 7.3. This event killed about 500 people and caused vast damages in the region. We calculated the static Coulomb stress changes due to this earthquake on the optimally oriented faults to investigate correlation of transferred stress and spatial distribution...
Article
Full-text available
Propagation of seismic waves through soil layers would drastically change the frequency content and amplitude-based features of ground motions at the surface. These alterations are known as seismic site effects. Computation of site effects of high-populated areas such as large cities is of great importance (e.g., it is used in development of seismi...
Article
The north Tehran fault (NTF) is known to be one of the most drastic sources of seismic hazard on the city of Tehran. In this study we provide broadband (0–10 Hz) ground motions for the city as a consequence of probable M7.2 earthquake on the NTF. Low frequency motions (0–2 Hz) are provided from spectral element dynamic simulation of 17 scenario mod...
Article
Full-text available
This study presents a time-dependent approach for seismic hazard in Tehran and surrounding areas. Hazard is evaluated by combining background seismic activity, and larger earthquakes may emanate from fault segments. Using available historical and paleoseismological data or empirical relation, the recurrence time and maximum magnitude of characteris...
Article
Full-text available
Aftershock hazard maps contain the essential information for search and rescue process, and re-occupation after a main-shock. Accordingly, the main purposes of this article are to study the aftershock decay parameters and to estimate the expected high-frequency ground motions (i.e., Peak Ground Acceleration (PGA)) for recent large earthquakes in th...
Article
Full-text available
A recently compiled, comprehensive and good quality strong motion database of the Iranian earthquakes has been used to develop local empirical equations for the prediction of Peak Ground Acceleration (PGA), and 5%-damped spectral accelerations (PSA) up to 4.0 s. The equations account for style of faulting, four site classes and use the horizont...
Article
Full-text available
In development of ground motion prediction equations (GMPEs), the residuals are assumed to have a log-normal distribution with a zero mean and a standard deviation, designated as sigma. Sigma has significant effect on evaluation of seismic hazard for designing important infrastructures such as nuclear power plants and dams. Both aleatory and episte...
Article
Full-text available
Surface ground motions can be obtained via various methods of analysis such as equivalent-linear (EL) and nonlinear (NL) one-dimensional numerical simulations. Selection of analysis method would be a challenging issue due to difficulty of input data preparation. The uncertainty inherent in soil parameters and shear wave velocity has significant imp...
Article
In this paper, the time-varying hazard of rupture of the northwestern segment of the North Tabriz Fault is evaluated using a statistical method and a recurrence time distribution, allowing for data and model parameter values uncertainties. The North Tabriz Fault is a main seismogenic fault in Northwestern Iran. The conditional probability of ruptur...
Article
Tehran is the most vulnerable urban area in Iran. Here, the characteristic earthquake model for the major earthquakes was integrated with the background seismicity to conduct the PSHA. For a 2475-year return period earthquake, a maximum PGA of 725 cm/s² and a maximum PGV of 60 cm/s were estimated. In next step, the simulated ground motions of the N...
Article
This study aims at conducting probabilistic seismic hazard analysis for the Sefidrud dam located near Rudbar City. For this purpose, firstly, the characteristic earthquake recurrence model for major earthquakes on individual main faults have been combined with the smaller (smoothed) background seismicity of the region. Then, appropriate ground moti...
Article
Full-text available
Ground-motion prediction equations (GMPEs) are essential tools in seismic hazard studies to estimate ground motions generated by potential seismic sources. Global GMPEs which are based on well-compiled global strong-motion databanks, have certain advantages over local GMPEs, including more sophisticated parameters in terms of distance, faulting sty...
Article
Full-text available
This paper presents a simulation of three components of near-field ground shaking recorded during the main shock at three stations of the September 16, 1978, Tabas (Mw = 7.4), Iran, earthquake, close to the causative fault. A hybrid method composed of a discrete wavenumber method developed by Bouchon (Bouchon in Bull Seismol Soc Am 71:959–971, 1981...
Article
Full-text available
Iranian strong-motion records as well as detailed conditions of their instrument sites and the characteristics of their causative seismic sources are compiled and processed. The dataset consists of 2286 three-component records from 461 Iranian earthquakes with at least two high quality records having moment magnitude from 3.9 to 7.3. These recor...
Article
The North Tehran Fault (NTF) represents an important source of seismic hazard to the city of Tehran, Iran, as it is known to be the causative fault of large historical earthquakes. In this study, the characteristics of long-period near-field ground-motions in the city of Tehran for M7.2 scenario earthquakes on the eastern segment of the NTF have be...
Article
Full-text available
Earthquake magnitude and P wave amplitude (Pmax) are important parameters for Earthquake Early Warning Systems (EEWS), yet their dependence on source mechanism, focal depth and epicentral distance (∆) has not been fully studied. We examined a method to estimate an earthquake's magnitude and epicentral distance using the initial part of P-wave data...
Conference Paper
Full-text available
The recent major plans for socio-economic-industrial development of Makran region necessitate a thorough investigation of the earthquake and tsunami risk assessment in the Makran region. Some major industrial development, such as, the oil and gas export terminals, petrochemical, steel factories, airports, industrial free zones, Navy base, and other...
Article
Full-text available
The original aim of the present study was to test the efficiency of some selected ground motion prediction equations (GMPEs) against small-to-moderate data recorded in the Iranian plateau. For this purpose, we applied three statistical tests including the Nash-Sutcliffe model efficiency coefficient (Nash and Sutcliffe, 1970), LH and LLH methods (Sc...
Article
The experience of past earthquakes has shown repeatedly that the characteristics of ground motions and resulting damages are highly dependent on the local condition of the site. It is clearly known that the underlying layers may amplify the earthquake excitation to some extent. This phenomenon is called the site-effects. The site amplification depe...
Article
The eastern part of the Iranian plateau is characterized by large and infrequent earthquakes with recurrence intervals of more than several hundred years. Given that previous observations and paleoseismological studies are insufficient for forecasting large earthquakes, we have developed a physics-based synthetic seismicity model for the fault syst...
Article
Full-text available
Motivated by the desire to have more information following the occurrence of damaging events, the main purpose of this article is to study aftershock sequence parameters in the Iranian plateau. To this end, the catalogue of the Iranian earthquakes between 2002 to the end of 2013 has been collected and homogenized among which 15 earthquakes have bee...
Article
Full-text available
The forecasting of large aftershocks is a preliminary and critical step in seismic hazard analysis and seismic risk management. From a statistical point of view, it relies entirely on the estimation of the properties of aftershock sequences using a set of laws with well-defined parameters. Since the frequentist and Bayesian approaches are common to...
Article
NW Iran is a region of active deformation in the Eurasia-Arabia collision zone. This high strain field has caused intensive faulting accompanied by several major (M 6> 6.5) earthquakes as it is evident from historical records. Whereas seismic data (i.e. instrumental and historical catalogs) are either short, or inaccurate and inhomogeneous, physics...
Article
Full-text available
Motivated by the desire to have more information following the occurrence of damaging events, the main purpose of this article is to study aftershock sequence parameters in the Iranian plateau. To this end, the catalogue of the Iranian earthquakes between 2002 to the end of 2013 has been collected and homoge-nized among which 15 earthquakes have be...
Article
Abstract In the present study, seismicity parameters (seismic activity, b-value and maximum regional magnitude) of the Iranian Plateau are computed for sites equally distributed all over the country on a grid of 1×1 decimal degree. The most complete available catalogue including historical and instrumental earthquakes of the plateau from 734 BC to...
Article
Full-text available
Northwestern Iran (Azerbaijan province), one of the most seismic regions of the country, has experienced many seismic events during its long history. The recent dual earthquake with M w = 6:4 and M w = 6:3 struck the Ahar-Varzaghan area in Azerbaijan province in 2012.8.11 and caused a lot of fatalities. In this paper, the varieties of several seism...
Article
The time-averaged shear-wave velocity to a depth of 30 meters (VS30) is widely used in various geotechnical and seismic issues such as ground motion prediction equations, determination of site class in building codes, and evaluation of site-effects. However, in many cases the velocity is not measured as deep as 30 m. Therefore, obtaining a correlat...
Article
North-western Iran (Azerbaijan province), one of the most seismic regions of the country, has experienced many seismic events during its long history. The recent dual earthquakes with Mw= 6.4 and Mw= 6.3 struck the Ahar-Varzaghan area in Azerbaijan province in 2012.8.11 and caused a lot of fatalities. In this paper the varieties of several seismic...
Article
Full-text available
In this paper, the long-term crustal flow of the Iranian Plateau is computed using a kinematic finite element model (NeoKinema software). Based on the iterated weighted least square method, the models are fitted to the newest data set of Iran including updated fault traces, geologic fault offset rates, geodetic benchmark velocities, principal stres...
Article
Here, the generalized inversion of S-wave amplitude spectra is employed for deriving the site response and S-wave attenuation (quality factor) in the northwest region of Iran. A total of 279 strong-motion accelerograms recorded at distances below 200 km from 41 earthquakes with moment magnitudes ranging from Mw 3.8 to 6.5 are used to determine the...
Article
Full-text available
The regional time- and magnitude-predictable model has been applied suc- cessfully in diverse regions of the world to describe the occurrence of main shocks. In the current study, the model has been calibrated against the historical and instrumental catalog of Iranian earthquakes. The Iranian plateau is divided into 15 seismogenic provinces; then,...
Article
Full-text available
In the first part of this study, a set of 87 ground-motion records, with closest distance to the rupture plane (Rrup) less than 200 km and averaged shear-wave velocity over the top 30 meters of the subsurface (Vs30) between 175 to 1400 m/s, recorded during the 2012 Ahar-Varzaghan dual earthquakes(Mw1=6.4, Mw2=6.3) were taken into account in order t...
Article
A total of 163 free-field acceleration time histories recorded at epicentral distances of up to 200 km from 32 earthquakes with moment magnitudes ranging from M w 4.9 to 7.4 have been used to investigate the predictive capabilities of the local, regional, and next generation attenuation (NGA) ground-motion prediction equations and determine their a...