Unified Scaling Law for Earthquakes as Applied to Assessment of Seismic Hazard and Associate Risks

2020 ◽  
Vol 56 (1) ◽  
pp. 83-94 ◽  
Author(s):  
A. K. Nekrasova ◽  
V. G. Kossobokov ◽  
I. A. Parvez ◽  
X. Tao
Keyword(s):  
Seismic Hazard ◽  
Scaling Law ◽  
Unified Scaling Law

scholarly journals Unified Scaling Law for Earthquakes: Space-Time Dependent Assessment in Friuli-Venezia Giulia Region

2021 ◽  
Vol 8 ◽  
Author(s):  
Anastasia Nekrasova ◽  
Antonella Peresan
Keyword(s):  
Seismic Hazard ◽  
Scaling Law ◽  
Seismic Hazard Assessment ◽  
Temporal Variations ◽  
Global Scale ◽  
Time Dependent ◽  
Seismic Region ◽  
Unified Scaling Law ◽  
Main Shocks ◽  
Friuli Venezia Giulia

The concept of the Unified Scaling Law for Earthquakes (USLE), which generalizes the Gutenberg-Richter relationship making use of the fractal distribution of earthquake sources in a seismic region, is applied to seismicity in the Friuli-Venezia Giulia region, FVG (Northeastern Italy) and its surroundings. In particular, the temporal variations of USLE coefficients are investigated, with the aim to get new insights in the evolving dynamics of seismicity within different tectonic domains of FVG. To this purpose, we consider all magnitude 2.0 or larger earthquakes that occurred in 1995–2019, as reported in the catalog compiled at the National Institute of Oceanography and Applied Geophysics (OGS catalog), within the territory of its homogeneous completeness. The observed variability of seismic dynamics for three sub-regions of the territory under investigation, delimited based on main geological and tectonic features, is characterized in terms of several moving averages, including: the inter-event time, τ; the cumulative Benioff strain release, Ʃ; the USLE coefficients estimated for moving six-years time intervals, and the USLE control parameter, η. We found that: 1) the USLE coefficients in FVG region are time-dependent and show up correlated; 2) the dynamical changes of τ, Ʃ, and η in the three sub-regions highlight a number of different seismic regimes; 3) seismic dynamics, prior and after the occurrence of the 1998 and 2004 Kobarid (Slovenia) strong main shocks, is characterized by different parameters in the related sub-region. The results obtained for the FVG region confirm similar analysis performed on a global scale, in advance and after the largest earthquakes worldwide. Moreover, our analysis highlights the spatially heterogeneous and non-stationary features of seismicity in the investigated territory, thus suggesting the opportunity of resorting to time-dependent estimates for improving local seismic hazard assessment. The applied methods and obtained parameters provide quantitative basis for developing suitable models and forecasting tools, toward a better characterization of future seismic hazard in the region.

Estimation of seismic hazard and risks for the Himalayas and surrounding regions based on Unified Scaling Law for Earthquakes

2013 ◽  
Vol 71 (1) ◽  
pp. 549-562 ◽  
Author(s):  
Imtiyaz A. Parvez ◽  
Anastasia Nekrasova ◽  
Vladimir Kossobokov
Keyword(s):  
Seismic Hazard ◽  
Scaling Law ◽  
Unified Scaling Law

On Prediction and Unified Correlation for Decay of Vertical Buoyant Jets

1979 ◽  
Vol 101 (3) ◽  
pp. 532-537 ◽  
Author(s):  
C. J. Chen ◽  
C. H. Chen
Keyword(s):  
Kinetic Energy ◽  
Scaling Law ◽  
Flow Characteristics ◽  
Heat Fluxes ◽  
Buoyant Jets ◽  
Numerical Result ◽  
Plume Region ◽  
Unified Scaling Law ◽  
Rate Of Dissipation ◽  
Decay Behavior

A differential turbulence model is used to predict the decay behavior of turbulent buoyant jets in a uniform environment at rest. The turbulent stresses and heat fluxes are modeled by the algebraic expressions while the differential transport equations are solved for the kinetic energy of turbulence, k, the rate of dissipation of turbulence kinetic energy, ε, and the fluctuating temperature T′2. The numerical result correlated with a unified scaling law was shown to fall into a single curve for the flows beyond the zone of flow establishment. The flow characteristics are then classified into a non-buoyant region, an intermediate region and a plume region. The predicted results show that the buoyant jets is accelerated in the zone of flow establishment. Equations for decay of velocity, density, and turbulent quantities are given from the non-buoyant region to the plume region for both plane and round buoyant jets.

scholarly journals Characterizing the Foreshock, Main Shock, and Aftershock Sequences of the Recent Major Earthquakes in Southern Alaska, 2016–2018

2020 ◽  
Vol 8 ◽  
Author(s):  
B. G. Bukchin ◽  
A. S. Fomochkina ◽  
V. G. Kossobokov ◽  
A. K. Nekrasova
Keyword(s):  
Control Parameter ◽  
Empirical Distribution ◽  
Scaling Law ◽  
Plate Boundary ◽  
Scaling Properties ◽  
Second Moments ◽  
The Pacific ◽  
Unified Scaling Law ◽  
Aftershock Sequences ◽  
Integral Estimation

For each of three major M ≥ 7.0 earthquakes (i.e., the January 24, 2016, M7.1 earthquake 86 km E of Old Iliamna; the January 23, 2018, M7.9 earthquake 280 km SE of Kodiak; and the November 30, 2018, M7.1 earthquake 14 km NNW of Anchorage, Alaska), the study considers characterization of the foreshock and aftershock sequences in terms of their variations and scaling properties, including the behavior of the control parameter η of the unified scaling law for earthquakes (USLE), along with a detailed analysis of the surface wave records for reconstruction of the source in the approximation of the second moments of the stress glut tensor to obtain integral estimation of its length, orientation, and development over time. The three major earthquakes at 600 km around Anchorage are, in fact, very different due to apparent complexity of earthquake flow dynamics in the orogenic corner of the Pacific and North America plate boundary. The USLE generalizes the classic Gutenberg-Richter relationship taking into account the self-similar scaling of the empirical distribution of earthquake epicenters. The study confirms the existence of the long-term periods of regional stability of the USLE control parameter that are interrupted by mid- or even short-term bursts of activity associated with major catastrophic events.

scholarly journals Scaling Interface Length Increase Rates in Richtmyer–Meshkov Instabilities

2013 ◽  
Vol 135 (3) ◽  
Author(s):  
V. Kilchyk ◽  
R. Nalim ◽  
C. Merkle
Keyword(s):  
Scaling Law ◽  
Scaling Analysis ◽  
Incoming Wave ◽  
Wave Refraction ◽  
Fuel Consumption Rate ◽  
Length Increase ◽  
Unified Scaling Law ◽  
Different Temperatures ◽  
Interface Length ◽  
Large Amplitude Wave

The interface area increase produced by large-amplitude wave refraction through an interface that separates fluids with different densities can have important physiochemical consequences, such as a fuel consumption rate increase in the case of a shock–flame interaction. Using the results of numerical simulations along with a scaling analysis, a unified scaling law of the interface length increase was developed applicable to shock and expansion wave refractions and both types of interface orientation with the respect to the incoming wave. To avoid a common difficulty in interface length quantification in the numerical tests, a sinusoidally perturbed interface was generated using gases with different temperatures. It was found that the rate of interface increase correlates almost linearly with the circulation deposited at the interface. When combined with earlier developed models of circulation deposition in Richtmyer–Meshkov instability, the obtained scaling law predicts dependence of interface dynamics on the basic problem parameters.

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