Seismic Hazard Assessment for the Korean Peninsula

Bulletin of the Seismological Society of America ◽

10.1785/0120200261 ◽

2021 ◽

Author(s):

Seongjun Park ◽

Tae-Kyung Hong ◽

Gyubyeong Rah

Keyword(s):

Seismic Hazard ◽

Ground Motion ◽

Korean Peninsula ◽

Active Faults ◽

Seismic Hazards ◽

Model Parameters ◽

Moderate Size ◽

South Central ◽

Seismicity Rates ◽

Recurrence Intervals

ABSTRACT The Korean Peninsula is located in a stable intraplate region with low-seismicity rates and long recurrence intervals of major earthquakes. Recent moderate-size earthquakes demonstrate possible occurrence of seismic damages in the Korean Peninsula. A probabilistic seismic hazard analysis based on instrumental and historical seismicity is applied for the Korean Peninsula. Three seismotectonic province models are used for area sources. Seven ground-motion prediction equations calibrated for bedrock condition are considered. Fault source models are not applied due to poor identification of active faults. A 500 yr long historical record of earthquakes includes moderate and large earthquakes of long recurrence intervals. The influences of model parameters are reflected through a logic-tree scheme. The process and results are verified by Monte Carlo ground-motion level simulation and benchmark tests. Relatively high-seismic hazards are modeled in the northwestern, south-central, and southeastern Korean Peninsula. The horizontal peak ground accelerations reach ∼0.06, 0.09, 0.13, 0.21, and 0.28g for periods of 25, 50, 100, 250, and 500 yr, respectively, with exceedance probability of 10%. Successive moderate-size earthquakes since the 11 March 2011 Tohoku–Oki megathrust earthquake have temporarily increased the seismic hazards in the southeastern peninsula.

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A Novel Bio Inspired Algorithm Based on Echolocation Mechanism of Bats for Seismic States Prediction

International Journal of Swarm Intelligence Research ◽

10.4018/ijsir.2017070101 ◽

2017 ◽

Vol 8 (3) ◽

pp. 1-18 ◽

Cited By ~ 2

Author(s):

Mohamed Elhadi Rahmani ◽

Abdelmalek Amine ◽

Reda Mohamed Hamou

Keyword(s):

Data Mining ◽

Seismic Hazard ◽

Ground Motion ◽

Geographic Area ◽

Seismic Hazards ◽

Data Discovery ◽

Distance Calculation ◽

Hard Problems ◽

Recorded Data ◽

Np Problems

Bio-inspired algorithms are sort of implementation of natural solutions to solve hard problems – so called NP problems. A seismic hazard is the probability that an earthquake will occur in a given geographic area, within a given window of time, and with ground motion intensity exceeding a given threshold. Seismic hazards prediction is one of the fields where data mining plays an important role. This paper presents a new bio-inspired algorithm motivated by the echolocation behavior of bats for seismic hazard states prediction in coal mines based on previously recorded data. It is a distance calculation based approach, Results were very satisfactory in a manner that encourage us to continue working on this approach. The implementation of the algorithm touches three fields of studies, data discovery or so called data mining, bio inspired techniques, and seismic hazards predictions.

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Planar Seismic Source Characterization Models Developed for Probabilistic Seismic Hazard Assessment of Istanbul

10.5194/nhess-2017-113 ◽

2017 ◽

Author(s):

Zeynep Gülerce ◽

Kadir Buğra Soyman ◽

Barış Güner ◽

Nuretdin Kaymakci

Keyword(s):

Seismic Hazard ◽

Hazard Assessment ◽

Seismic Hazard Assessment ◽

Seismic Source ◽

Probabilistic Seismic Hazard Assessment ◽

Model Parameters ◽

Probabilistic Seismic Hazard ◽

Maximum Magnitude ◽

Source Characterization ◽

Seismicity Rates

Abstract. This contribution provides an updated planar seismic source characterization (SSC) model to be used in the probabilistic seismic hazard assessment (PSHA) for Istanbul. It defines planar rupture systems for the four main segments of North Anatolian Fault Zone (NAFZ) that are critical for the PSHA of Istanbul: segments covering the rupture zones of 1999 Kocaeli and Düzce earthquakes, Central Marmara, and Ganos/Saros segments. In each rupture system, the source geometry is defined in terms of fault length, fault width, fault plane attitude, and segmentation points. Activity rates and the magnitude recurrence models for each rupture system are established by considering geological and geodetic constraints and are tested based on the observed seismicity that associated with the rupture system. Uncertainty in the SSC model parameters (e.g. b-value, maximum magnitude, weights of the rupture scenarios) is considered in the logic tree. To acknowledge the effect of earthquakes that are not associated with the defined rupture systems on the hazard, a background zone is introduced and the seismicity rates in the background zone are calculated using smoothed-seismicity approach. The state-of-the-art SSC model presented here is the first fully-documented and ready-to-use fault-based SSC model developed for the PSHA of Istanbul.

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Planar seismic source characterization models developed for probabilistic seismic hazard assessment of Istanbul

Natural Hazards and Earth System Science ◽

10.5194/nhess-17-2365-2017 ◽

2017 ◽

Vol 17 (12) ◽

pp. 2365-2381 ◽

Cited By ~ 2

Author(s):

Zeynep Gülerce ◽

Kadir Buğra Soyman ◽

Barış Güner ◽

Nuretdin Kaymakci

Keyword(s):

Seismic Hazard ◽

Hazard Assessment ◽

Seismic Hazard Assessment ◽

Seismic Source ◽

Probabilistic Seismic Hazard Assessment ◽

Model Parameters ◽

Probabilistic Seismic Hazard ◽

Maximum Magnitude ◽

Source Characterization ◽

Seismicity Rates

Abstract. This contribution provides an updated planar seismic source characterization (SSC) model to be used in the probabilistic seismic hazard assessment (PSHA) for Istanbul. It defines planar rupture systems for the four main segments of the North Anatolian fault zone (NAFZ) that are critical for the PSHA of Istanbul: segments covering the rupture zones of the 1999 Kocaeli and Düzce earthquakes, central Marmara, and Ganos/Saros segments. In each rupture system, the source geometry is defined in terms of fault length, fault width, fault plane attitude, and segmentation points. Activity rates and the magnitude recurrence models for each rupture system are established by considering geological and geodetic constraints and are tested based on the observed seismicity that is associated with the rupture system. Uncertainty in the SSC model parameters (e.g., b value, maximum magnitude, slip rate, weights of the rupture scenarios) is considered, whereas the uncertainty in the fault geometry is not included in the logic tree. To acknowledge the effect of earthquakes that are not associated with the defined rupture systems on the hazard, a background zone is introduced and the seismicity rates in the background zone are calculated using smoothed-seismicity approach. The state-of-the-art SSC model presented here is the first fully documented and ready-to-use fault-based SSC model developed for the PSHA of Istanbul.

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Time-dependent seismic hazard and risk due to wastewater injection in Oklahoma

Earthquake Spectra ◽

10.1177/8755293020988020 ◽

2021 ◽

pp. 875529302098802

Author(s):

Iason Grigoratos ◽

Paolo Bazzurro ◽

Ellen Rathje ◽

Alexandros Savvaidis

Keyword(s):

Seismic Hazard ◽

Ground Motion ◽

Seismic Risk ◽

Risk Model ◽

Time Dependent ◽

Economic Losses ◽

Motion Model ◽

Seismicity Rate ◽

Ground Motion Model ◽

Seismicity Rates

In the past decade, Oklahoma has experienced unprecedented seismicity rates, following an increase in the volumes of wastewater that are being disposed underground. In this article, we perform a probabilistic assessment of the time-dependent seismic hazard in Oklahoma and incorporate these results into an integrated seismic risk model to assess the evolution of the statewide economic losses, including a conservative forecast through 2030. Our risk model employs an injection-driven earthquake rate model, a region-specific ground motion model, a recent Vs30 map, HAZUS exposure data and updated vulnerability curves for both structural and nonstructural elements, and contents. The calculations are performed using a stochastic Monte Carlo–based approach implemented in the OpenQuake engine. The resulting seismic hazard maps illustrate the incompatibility of the regional seismic provisions with the current seismicity. In 2015, in particular, the induced seismic hazard in several places in Oklahoma was higher than along the San Andreas fault. During the peak of seismicity in 2015, the seismic risk was 275 times higher than the background level, with the vast majority of losses originating from damages to nonstructural elements and contents. Our direct economic loss estimates are in reasonable agreement with the paid insurance claims, but show significant sensitivity to the ground motion model selection. The proposed risk model, with possible regular updates on the seismicity rate forecast, can help stakeholders define acceptable production levels.

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Seismic hazard for the Trans Adriatic Pipeline (TAP). Part 2: broadband scenarios at the Fier Compressor Station (Albania)

Bulletin of Earthquake Engineering ◽

10.1007/s10518-021-01122-z ◽

2021 ◽

Author(s):

L. Moratto ◽

A. Vuan ◽

A. Saraò ◽

D. Slejko ◽

C. Papazachos ◽

...

Keyword(s):

Seismic Hazard ◽

Ground Motion ◽

Hazard Assessment ◽

Transfer Functions ◽

Active Faults ◽

Seismic Hazard Assessment ◽

Probabilistic Seismic Hazard Assessment ◽

Compressor Station ◽

Damage Functions ◽

Worst Case

AbstractTo ensure environmental and public safety, critical facilities require rigorous seismic hazard analysis to define seismic input for their design. We consider the case of the Trans Adriatic Pipeline (TAP), which is a pipeline that transports natural gas from the Caspian Sea to southern Italy, crossing active faults and areas characterized by high seismicity levels. For this pipeline, we develop a Probabilistic Seismic Hazard Assessment (PSHA) for the broader area, and, for the selected critical sites, we perform deterministic seismic hazard assessment (DSHA), by calculating shaking scenarios that account for the physics of the source, propagation, and site effects. This paper presents a DSHA for a compressor station located at Fier, along the Albanian coastal region. Considering the location of the most hazardous faults in the study site, revealed by the PSHA disaggregation, we model the ground motion for two different scenarios to simulate the worst-case scenario for this compressor station. We compute broadband waveforms for receivers on soft soils by applying specific transfer functions estimated from the available geotechnical data for the Fier area. The simulations reproduce the variability observed in the ground motion recorded in the near-earthquake source. The vertical ground motion is strong for receivers placed above the rupture areas and should not be ignored in seismic designs; furthermore, our vertical simulations reproduce the displacement and the static offset of the ground motion highlighted in recent studies. This observation confirms the importance of the DSHA analysis in defining the expected pipeline damage functions and permanent soil deformations.

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Geologic and geodetic constraints on the seismic hazard of Malawi’s active faults: The Malawi Seismogenic Source Database (MSSD)

10.5194/nhess-2021-306 ◽

2021 ◽

Author(s):

Jack N. Williams ◽

Luke N. J. Wedmore ◽

Åke Fagereng ◽

Maximilian J. Werner ◽

Hassan Mdala ◽

...

Keyword(s):

Seismic Hazard ◽

Active Fault ◽

Active Faults ◽

Slip Rate ◽

Slip Rates ◽

Source Database ◽

Seismogenic Sources ◽

Seismogenic Source ◽

Recurrence Intervals ◽

Seismic Reflector

Abstract. Active fault data are commonly used in seismic hazard assessments, but there are challenges in deriving the slip rate, geometry, and frequency of earthquakes along active faults. Herein, we present the open-access geospatial Malawi Seismogenic Source Database (MSSD), which describes the seismogenic properties of faults that have formed during East African rifting in Malawi. We first use empirical observations to geometrically classify active faults into section, fault, and multi-fault seismogenic sources. For sources in the North Basin of Lake Malawi, slip rates can be derived from the vertical offset of a seismic reflector that is estimated to be 75 ka based on dated core. Elsewhere, slip rates are constrained from advancing a ‘systems-based’ approach that partitions geodetically-derived rift extension rates in Malawi between seismogenic sources using a priori constraints on regional strain distribution in magma-poor continental rifts. Slip rates are then combined with source geometry and empirical scaling relationships to estimate earthquake magnitudes and recurrence intervals, and their uncertainty is described from the variability of outcomes from a logic tree used in these calculations. We find that for sources in the Lake Malawi’s North Basin, where slip rates can be derived from both the geodetic data and the offset seismic reflector, the slip rate estimates are within error of each other, although those from the offset reflector are higher. Sources in the MSSD are 5–200 km long, which implies that large magnitude (MW 7–8) earthquakes may occur in Malawi. Low slip rates (0.05–2 mm/yr), however, mean that the frequency of such events will be low (recurrence intervals ~103–104 years). The MSSD represents an important resource for investigating Malawi’s increasing seismic risks and provides a framework for incorporating active fault data into seismic hazard assessment in other tectonically active regions.

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Probabilistic Seismic Hazard Assessment in Countries With Low Seismicity

Volume 8: Seismic Engineering ◽

10.1115/pvp2014-28937 ◽

2014 ◽

Author(s):

Katerina Demjancukova ◽

Dana Prochazkova

Keyword(s):

Seismic Hazard ◽

Ground Motion ◽

Hazard Assessment ◽

Seismic Activity ◽

Power Plants ◽

Seismic Hazard Assessment ◽

Seismic Hazards ◽

Probabilistic Seismic Hazard Assessment ◽

Geological Unit ◽

Fault Displacement

The region of the Czech Republic is mostly composed of the Bohemian Massif which is considered as a geological unit with low seismic activity. Nevertheless, all critical objects as the nuclear power plants, big dams etc. are built as aseismic structures. The nuclear installations have to satisfy the IAEA safety standards and requirements. One of important phenomena that have to be involved in the PSHA process is the diffuse seismicity. In 2010 International Atomic Energy Agency issued a specific safety guide SSG-9 Seismic Hazards in Site Evaluation for Nuclear Installations. The key chapters are focused on general recommendations, necessary information and investigations (database), construction of a regional seismotectonic model, evaluation of the ground motion hazard, probabilistic seismic hazards analysis (PSHA), deterministic seismic hazards analysis, potential for fault displacement at the site, design basis ground motion, fault displacement and other hazards, evaluation of seismic hazards for nuclear installations other than NPPs. In the paper a numerical example of seismic hazard assessment will be presented with emphasis on problems and particularities related to PSHA in countries with low seismic activity.

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A probabilistic seismic hazard model for Mainland China

Earthquake Spectra ◽

10.1177/8755293020910754 ◽

2020 ◽

Vol 36 (1_suppl) ◽

pp. 181-209 ◽

Cited By ~ 2

Author(s):

Yufang Rong ◽

Xiwei Xu ◽

Jia Cheng ◽

Guihua Chen ◽

Harold Magistrale ◽

...

Keyword(s):

Seismic Hazard ◽

Ground Motion ◽

Active Faults ◽

Mainland China ◽

Hazard Model ◽

Source Zone ◽

Probabilistic Seismic Hazard ◽

Earthquake Catalog ◽

Geodetic Strain Rate ◽

Geodetic Strain

We construct a probabilistic seismic hazard model for mainland China by integrating historical earthquakes, active faults, and geodetic strain rates. We delineate large seismic source zones based on geologic and seismotectonic characteristics. For each source zone, a tapered Gutenberg–Richter (TGR) distribution is used to model the total seismic activity rates. The TGR a- and b-values are calculated using a new earthquake catalog, while corner magnitudes are constrained using the seismic moment rate inferred from a geodetic strain rate model. For hazard calculations, the total TGR distribution is split into two parts, with smaller ( MW < 6.5) earthquakes being distributed within the zone using a smoothed seismicity method, and larger earthquakes put both onto active faults, based on fault slip rates and dimensions, and into the zone as background seismicity. We select ground motion models by performing residual analysis using ground motion recordings. Site amplifications are considered based on a site condition map developed using geology as a proxy. The resulting seismic hazard is consistent with the fifth-generation national seismic hazard model for most major cities.

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Modelling earthquake rates and associated uncertainties in the Marmara Region, Turkey

Natural Hazards and Earth System Science ◽

10.5194/nhess-21-2733-2021 ◽

2021 ◽

Vol 21 (8) ◽

pp. 2733-2751

Author(s):

Thomas Chartier ◽

Oona Scotti ◽

Hélène Lyon-Caen ◽

Keith Richard-Dinger ◽

James H. Dieterich ◽

...

Keyword(s):

Seismic Hazard ◽

Epistemic Uncertainty ◽

Active Faults ◽

System Level ◽

Fault System ◽

Marmara Region ◽

Logic Tree ◽

Local Data ◽

Seismicity Rates ◽

Model Complex

Abstract. Modelling the seismic potential of active faults and the associated epistemic uncertainty is a fundamental step of probabilistic seismic hazard assessment (PSHA). We use SHERIFS (Seismic Hazard and Earthquake Rate In Fault Systems), an open-source code allowing us to build hazard models including earthquake ruptures involving several faults, to model the seismicity rates on the North Anatolian Fault (NAF) system in the Marmara Region. Through an iterative approach, SHERIFS converts the slip rate on the faults into earthquake rates that follow a magnitude frequency distribution (MFD) defined at the fault system level, allowing us to model complex multi-fault ruptures and off-fault seismicity while exploring the underlying epistemic uncertainties. In a logic tree, we explore uncertainties concerning the locking state of the NAF in the Sea of Marmara, the maximum possible rupture in the system, the shape of the MFD and the ratio of off-fault seismicity. The branches of the logic tree are weighted according to the match between the modelled earthquake rate and the earthquake rates calculated from the local data, earthquake catalogue and palaeoseismicity. In addition, we use the result of the physics-based earthquake simulator RSQSim to inform the logic tree and increase the weight on the hypotheses that are compatible with the result of the simulator. Using both the local data and the simulator to weight the logic tree branches, we are able to reduce the uncertainties affecting the earthquake rates in the Marmara Region. The weighted logic tree of models built in this study will be used in a following article to calculate the probability of collapse of a building in Istanbul.

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