Early assessment of seismic hazard in terms of Voronezh massif-Moscow Depression contact

Purpose is to develop a system approach for early assessment of areas being of high seismic hazard and characterizing by low stability of rock mass relative to external loads. Methods. Well cores have been assessed down to 30 depth and seismic observations have been accumulated. Complexes of field geophysics methods have been applied for the research as well as remote sensing materials, digital model of surface relief, and techniques of qualitative and quantitative interpretation. Findings. Seismic hazard map has been formed in terms of seismic intensification and ground displacement units. The abovementioned is quite reliable but a cost-based result involving early assessments of high seismic hazard areas to infill network of geophysical measurements in the neighbourhood of the areas for their further quantitative characterization. It has been identified that rare well network and definite geophysical lines, run under conditions of a complex terrain, cannot localize the areas of high seismic hazard to focus builders on the enforcement of certain components of the erected structures. It has been defined that end result of the prognostic developments takes a shape of mapping of local areas with the decreased stability of upper share of the geological section supported by further measurements by means of a common depth point method (CDP). Comparison of potential secondary earthquake sources with high permeability zones makes it possible to predict highly reliable areas of the increased seismic magnitude. Originality.For the first time, interpretation techniques have been adapted to describe parametrically nonpotential geofields (i.e. optical density of remote basis; and relative elevation), accepted during the steps of potential field processing, with the use of wave analogies. Practical implications.The methods have been developed helping optimize field geological and geophysical operations in terms of area and well number as well as measuring stakes under the conditions of the limited prior data amount.

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Seismic hazard assessment in the Ibero-Maghreb region

Annals of Geophysics ◽

10.4401/ag-3774 ◽

1999 ◽

Vol 42 (6) ◽

Author(s):

M. J. Jiménez ◽

M. García-Fernández

Keyword(s):

Seismic Hazard ◽

Hazard Assessment ◽

Seismic Hazard Assessment ◽

Earthquake Hazard ◽

Seismic Source ◽

Common Procedure ◽

Fruitful Cooperation ◽

Seismic Hazard Map ◽

First Time ◽

Regional Earthquake

The contribution of the Ibero-Maghreb region to the global GSHAP map has been the result of a fruitful cooperation among the participants in the established Working Group including representatives from Algeria, Morocco, Portugal, Spain and Tunisia and coordinated by ICTJA-CSIC, Spain. For the first time, a map of regional seismic source zones is presented, and agreement on a common procedure for hazard computation in the region has been achieved. The computed Ibero-Maghreb seismic hazard map constitutes the first step towards a uniform hazard assessment for the region. Further joint regional efforts are still needed for earthquake hazard studies based on a homogeneous regional earthquake catalogue. Ongoing initiatives in relation to seismic hazard assessment in the Mediterranean should profit both from these results and the established cooperation among different groups in the region as well as contribute to future regional studies.

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Seismic Hazard Map for Papua Island

International Review of Civil Engineering (IRECE) ◽

10.15866/irece.v9i2.14090 ◽

2018 ◽

Vol 9 (2) ◽

pp. 57

Author(s):

Lalu Makrup ◽

Arif Hariyanto ◽

Setya Winarno

Keyword(s):

Seismic Hazard ◽

Hazard Map ◽

Seismic Hazard Map

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Challenges and Opportunities in Turning Large U.S. Archives of Analog Seismograms into a Modern Usable Resource

Seismological Research Letters ◽

10.1785/0220200053 ◽

2020 ◽

Vol 91 (3) ◽

pp. 1531-1541

Author(s):

Paul G. Richards ◽

Margaret Hellweg

Keyword(s):

Seismic Hazard ◽

Scientific Information ◽

Practical Experience ◽

Earthquake Physics ◽

Timing Information ◽

Earthquake Sources ◽

Challenges And Opportunities ◽

Test Ban ◽

Level Of Effort

Abstract Quantitative seismology is based firmly on the analysis of actual ground motions, and the transition to digital recording in the 1980s enabled sophisticated new capabilities to extract useful results from waveforms. With some effort, these tools can also be applied to analog records. Focusing on assets available within U.S. institutions, we review the necessary steps and the challenges in enabling “data rescue”—that is, preserving the scientific information latent in large analog seismogram archives and making it usable. They include: determining what assets are available (the analog seismogram archives held by various institutions, with associated metadata on instrument responses, station locations, and timing information); developing a consensus on the top level of a triage process (which analog records most definitely should be rescued?); deciding the level of quality needed in copying original seismograms to media suitable for digitizing; assessing the relative merits of scanning and digitizing; and, the need for a community service in distributing scans and digital records, as they accumulate. The necessary level of effort can benefit from practical experience. For example, specific studies have used digitized versions of analog recordings to model earthquake sources and assess seismic hazard. Other studies have used them to gain experience with nuclear explosion signals recorded at regional distances, noting that regional signals enable explosions to be monitored down to levels much lower than those attainable teleseismically. The opportunities presented by large archives of analog seismograms include the insights they present to current and future seismologists studying earthquakes and explosions, into the practical areas of assessing seismic hazard, monitoring for test ban compliance down to low explosion yields—and prompt characterization of actual explosions should they occur, as well the traditional academic pursuit of a better understanding of earthquake physics.

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Proposed Seismic Hazard Map For Conventional Bridge Code In Indonesia

Proceedings of the 18th Southeast Asian Geotechnical Conference (18SEAGC) & Inaugural AGSSEA Conference (1AGSSEA) ◽

10.3850/978-981-07-4948-4_232 ◽

2013 ◽

Author(s):

Fahmi Aldiamar ◽

Masyhur Irsyam ◽

I. Wayan Sengara ◽

M. Asrurifak

Keyword(s):

Seismic Hazard ◽

Hazard Map ◽

Seismic Hazard Map

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C-Band Dual-Doppler Retrievals in Complex Terrain: Improving the Knowledge of Severe Storm Dynamics in Catalonia

Remote Sensing ◽

10.3390/rs12182930 ◽

2020 ◽

Vol 12 (18) ◽

pp. 2930 ◽

Cited By ~ 1

Author(s):

Anna del Moral ◽

Tammy M. Weckwerth ◽

Tomeu Rigo ◽

Michael M. Bell ◽

María Carmen Llasat

Keyword(s):

Complex Terrain ◽

Prediction Models ◽

Weather Prediction ◽

Warning System ◽

Wind Fields ◽

Severe Thunderstorm ◽

Radar Network ◽

Storm Dynamics ◽

Storm Cells ◽

First Time

Convective activity in Catalonia (northeastern Spain) mainly occurs during summer and autumn, with severe weather occurring 33 days per year on average. In some cases, the storms have unexpected propagation characteristics, likely due to a combination of the complex topography and the thunderstorms’ propagation mechanisms. Partly due to the local nature of the events, numerical weather prediction models are not able to accurately nowcast the complex mesoscale mechanisms (i.e., local influence of topography). This directly impacts the retrieved position and motion of the storms, and consequently, the likely associated storm severity. Although a successful warning system based on lightning and radar observations has been developed, there remains a lack of knowledge of storm dynamics that could lead to forecast improvements. The present study explores the capabilities of the radar network at the Meteorological Service of Catalonia to retrieve dual-Doppler wind fields to study the dynamics of Catalan thunderstorms. A severe thunderstorm that splits and a tornado-producing supercell that is channeled through a valley are used to demonstrate the capabilities of an advanced open source technique that retrieves dynamical variables from C-band operational radars in complex terrain. For the first time in the Iberian Peninsula, complete 3D storm-relative winds are obtained, providing information about the internal dynamics of the storms. This aids in the analyses of the interaction between different storm cells within a system and/or the interaction of the cells with the local topography.

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Integrating faults and past earthquakes into a probabilistic seismic hazard model for peninsular Italy

Natural Hazards and Earth System Science ◽

10.5194/nhess-17-2017-2017 ◽

2017 ◽

Vol 17 (11) ◽

pp. 2017-2039 ◽

Cited By ~ 13

Author(s):

Alessandro Valentini ◽

Francesco Visini ◽

Bruno Pace

Keyword(s):

Seismic Hazard ◽

Seismic Activity ◽

Grid Point ◽

Active Faults ◽

Gaussian Model ◽

Probabilistic Seismic Hazard ◽

Maximum Magnitude ◽

Slip Rates ◽

Earthquake Sources ◽

The Impact

Abstract. Italy is one of the most seismically active countries in Europe. Moderate to strong earthquakes, with magnitudes of up to ∼ 7, have been historically recorded for many active faults. Currently, probabilistic seismic hazard assessments in Italy are mainly based on area source models, in which seismicity is modelled using a number of seismotectonic zones and the occurrence of earthquakes is assumed uniform. However, in the past decade, efforts have increasingly been directed towards using fault sources in seismic hazard models to obtain more detailed and potentially more realistic patterns of ground motion. In our model, we used two categories of earthquake sources. The first involves active faults, and using geological slip rates to quantify the seismic activity rate. We produced an inventory of all fault sources with details of their geometric, kinematic, and energetic properties. The associated parameters were used to compute the total seismic moment rate of each fault. We evaluated the magnitude–frequency distribution (MFD) of each fault source using two models: a characteristic Gaussian model centred at the maximum magnitude and a truncated Gutenberg–Richter model. The second earthquake source category involves grid-point seismicity, with a fixed-radius smoothed approach and a historical catalogue were used to evaluate seismic activity. Under the assumption that deformation is concentrated along faults, we combined the MFD derived from the geometry and slip rates of active faults with the MFD from the spatially smoothed earthquake sources and assumed that the smoothed seismic activity in the vicinity of an active fault gradually decreases by a fault-size-driven factor. Additionally, we computed horizontal peak ground acceleration (PGA) maps for return periods of 475 and 2475 years. Although the ranges and gross spatial distributions of the expected accelerations obtained here are comparable to those obtained through methods involving seismic catalogues and classical zonation models, the spatial pattern of the hazard maps obtained with our model is far more detailed. Our model is characterized by areas that are more hazardous and that correspond to mapped active faults, while previous models yield expected accelerations that are almost uniformly distributed across large regions. In addition, we conducted sensitivity tests to determine the impact on the hazard results of the earthquake rates derived from two MFD models for faults and to determine the relative contributions of faults versus distributed seismic activity. We believe that our model represents advancements in terms of the input data (quantity and quality) and methodology used in the field of fault-based regional seismic hazard modelling in Italy.

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Seismic magnitude conversion and its effect on seismic hazard analysis

Journal of Seismology ◽

10.1007/s10950-019-09826-1 ◽

2019 ◽

Vol 23 (4) ◽

pp. 623-647 ◽

Cited By ~ 1

Author(s):

P. Anbazhagan ◽

A. Balakumar

Keyword(s):

Seismic Hazard ◽

Hazard Analysis ◽

Seismic Hazard Analysis ◽

Magnitude Conversion ◽

Seismic Magnitude

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Earthquake-Induced Landslide Risk Assessment: An Example from Sakhalin Island, Russia

Geosciences ◽

10.3390/geosciences9070305 ◽

2019 ◽

Vol 9 (7) ◽

pp. 305 ◽

Cited By ~ 3

Author(s):

Alexey Konovalov ◽

Yuriy Gensiorovskiy ◽

Valentina Lobkina ◽

Alexandra Muzychenko ◽

Yuliya Stepnova ◽

...

Keyword(s):

Risk Assessment ◽

Seismic Hazard ◽

Ground Motion ◽

Sakhalin Island ◽

Landslide Risk ◽

Hazard Map ◽

Probabilistic Technique ◽

Landslide Risk Assessment ◽

Seismic Hazard Map ◽

The Given

Damages caused by earthquake-induced ground effects can be of the order or significantly exceed the expected damages from ground shaking. A new probabilistic technique is considered in this study for earthquake-induced landslide risk assessment. A fully probabilistic technique suggests a multi-stage hazard assessment. These stages include the determination of seismic hazard curves and landslide probabilistic models, a vulnerability assessment, and geotechnical investigations. At each of the stages, the uncertainties should be carefully analyzed. A logic tree technique, which handles all available models and parameters, was used in the study. The method was applied considering child education facilities located at the foot of a natural slope in the south of Sakhalin Island which is known as an active seismic and land sliding area. The significant differences in the ground motion scenario in terms of the 475-year seismic hazard map and the fully probabilistic approach considered suggests that seismic landslide risk could be underestimated or overestimated when using the 475-year seismic hazard map for risk assessment. The given approach follows the rational risk management idea that handles well all possible ground motion scenarios, slope models, and parameters. The authors suggest that the given approach can improve geotechnical studies of slope stability.

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