scholarly journals An analytic method for separating local from regional effects on macroseismic intensity

1995 ◽  
Vol 38 (1) ◽  
Author(s):  
P. Tosi ◽  
V. De Rubeis ◽  
C. Gasparini
Keyword(s):  
Macroseismic Intensity ◽  
Analytic Method ◽  
Macroseismic Data ◽  
Regional Trend ◽  
Regional Effects ◽  
Republic Of Macedonia ◽  
Macroseismic Field ◽  
Qualitative Nature ◽  
Local Intensity ◽  
Yugoslavian Republic

nterpretation of macroseismic data is hazardous, due to its qualitative nature. This, linked with errors in eval- uation,) and the variations of local intensity, makes it difficult to draw valid conclusions. This study presents a statistical method as the basis for distinguishing the diverse components that constitute a macroseismic field. The method is based on the polar transformation of the coordinate system and on the analysis of the fractal di- mension of the intensity values, exposed to the gradually increasing action of a two-dimensional filter. The fractal dimension is shown to be an ideaI parameter with which to measure out the filtering process in order to separate the local components from the regional trend. This method has been applied to two Italian events and to an earthquake which took pIace in the Former Yugoslavian Republic of Macedonia (FYROM).

scholarly journals A Reappraisal of the Lurøy, Norway, Earthquake of 31 August 1819

2020 ◽  
Vol 91 (5) ◽  
pp. 2462-2472 ◽  
Author(s):  
Päivi B. Mäntyniemi ◽  
Mathilde B. Sørensen ◽  
Tatiana N. Tatevossian ◽  
Ruben E. Tatevossian ◽  
Björn Lund
Keyword(s):  
Historical Seismicity ◽  
Macroseismic Intensity ◽  
Macroseismic Data ◽  
Sources Of Information ◽  
Royal Swedish Academy ◽  
Intensity Assessment ◽  
Adequate Information ◽  
Data Points ◽  
Academy Of Sciences ◽  
Written Sources

Abstract Archives and libraries were visited to find previously unknown documents testifying to the Lurøy, Norway, earthquake of 31 August 1819 in northernmost continental Europe. The focus here is on Sweden, Finland, and Russia, which are important for determining the area of perceptibility east of Norway. The new written sources include 12 notes or entries in original archived documents, six contemporary newspaper reports, and two recollections written down years later. The original documentation uncovered is contributory to establishing the authenticity of the observations in Finland and Sweden. The dates of the original documentation allow tracing of the dissemination of eyewitness accounts in writing from the inner area of perceptibility southward to the larger documentation and population centers. New sources of information include weather reports of the Royal Swedish Academy of Sciences, minutes of its meetings, and correspondence sent to the Senate in Finland. The minutes of meetings of the Academy indicate that ample data were collected in the Swedish province of Västerbotten. We found no original Russian documentation but uncovered national newspapers that are more reliable than the previously used Parisian newspaper. To increase transparency, we provide the first list of macroseismic data points (MDPs) including the respective documentation that testify to the Lurøy earthquake. A macroseismic intensity was assigned to a locality, using the European Macroseismic Scale of 1998, when adequate information was available. Accounting for the uncertainty of intensity assessment, the magnitude was estimated as moment magnitude M=5.9±0.2, reconfirming the ranking as the largest onshore or nearshore earthquake in the historical seismicity record of Fennoscandia. In addition to the reappraisal of the 31 August 1819 earthquake, a macroseismic map is provided for the earthquake of 17 February 1819, which was felt in northern Finland and Sweden. Some of its MDPs were previously associated with the Lurøy earthquake.

scholarly journals Inferences on the source mechanisms of the 1930 Irpinia (Southern Italy) earthquake from simulations of the kinematic rupture process

2009 ◽  
Vol 47 (6) ◽  
Author(s):  
A. Emolo ◽  
G. Iannaccone ◽  
A. Zollo ◽  
A. Gorini
Keyword(s):  
Ground Motion ◽  
Southern Italy ◽  
Empirical Relationship ◽  
Normal Fault ◽  
Rupture Process ◽  
Macroseismic Data ◽  
Macroseismic Field ◽  
Good Reproduction ◽  
Source Mechanisms ◽  
Source Models

We examine here a number of parameters that define the source of the earthquake that occurred on 23rd July 1930 in Southern Italy (in the Irpinia region). Starting from the source models proposed in different studies, we have simulated the acceleration field for each hypothesized model, and compared it with the macroseismic data. We then used the hybrid stochastic-deterministic technique proposed by Zollo et al. (1997) for the simulation of the ground motion associated with the rupture of an extended fault. The accelerations simulated for several sites were associated with the intensities using the empirical relationship proposed by Trifunac and Brady (1975), before being compared with the available data from the macroseismic catalogue. A good reproduction of the macroseismic field is provided by a normal fault striking in Apenninic direction (approximately NW-SE) and dipping 55° toward the SW.

scholarly journals MIDDLE URAL EARTHQUAKE on October 18, 2015, ML=4.7, I0=6

2021 ◽  
pp. 314-323
Author(s):  
F. Verkholantsev ◽  
I. Gabsatarova ◽  
N. Guseva ◽  
R. Dyagilev
Keyword(s):  
Focal Mechanism ◽  
Seismic Effect ◽  
Middle Urals ◽  
Macroseismic Data ◽  
Macroseismic Field ◽  
Tectonic Position ◽  
The Village

Instrumental and macroseismic data on the earthquake of 18.10.2015 at 21h44m UTC, ML=4.7, I0=6 in the Sverdlovsk region, near the village of Sabik (Middle Urals) are presented. A significant amount of macroseismic data made it possible to build a map of the macroseismic field, taking into account the anisotropic nature of the propagation of the seismic effect. Taking into account the decision of the focal mechanism, the tectonic position of the source was substantiated.

scholarly journals An Oldest Dryas glacier expansion on Mount Pelister (Former Yugoslavian Republic of Macedonia) according to 10Be cosmogenic dating

2017 ◽  
Vol 175 (1) ◽  
pp. 100-110 ◽  
Author(s):  
Adriano Ribolini ◽  
Monica Bini ◽  
Ilaria Isola ◽  
Matteo Spagnolo ◽  
Giovanni Zanchetta ◽  
...  
Keyword(s):  
Cosmogenic Dating ◽  
Republic Of Macedonia ◽  
Yugoslavian Republic

scholarly journals Bayesian analysisof a probability distribution for local intensity attenuation

2009 ◽  
Vol 47 (5) ◽  
Author(s):  
R. Rotondi ◽  
G. Zonno
Keyword(s):  
Epicentral Distance ◽  
Central Italy ◽  
Random Variable ◽  
Macroseismic Intensity ◽  
Propagation Path ◽  
Physical Parameters ◽  
Intensity Attenuation ◽  
Data Points ◽  
Local Intensity ◽  
Intensity Decay

Intensity attenuation and its variation as a function of the distance and earthquake size is still a critical issue in evaluating seismic hazard. We present a method that allows us to incorporate additional information from the historical earthquake felt reports in the probability estimation of local intensity attenuation. The approach is based on two ideas: a) standard intensity versus epicentral distance relationships constitute an unnecessary filter between observations and estimates; and b) the intensity decay process is affected by many, scarcely known elements (the physical parameters of the source, propagation path effects, building vulnerability, the semi-qualitative character of macroseismic scales, etc.). Hence intensity decay should be treated as a random variable as is the macroseismic intensity. We assume here that decay, defined on the set {0,1, ..., I0}, follows a binomial distribution with parameters (I0, p); p depends on the distance from the epicenter and is related to the probability of null decay at that distance. According to the Bayesian approach this p parameter is, in turn, a Beta random variable. The observations related to earthquakes with their epicenter outside the area concerned, but belonging to homogeneous zones, are used as prior knowledge of the phenomenon, while the data points of events inside the area are used to update the estimates through the posterior means of the quantities involved. Our methodology is described in detail in an application to the Umbria-Marche area in Central Italy. The data sets examined are the macroseismic intensity database DOM4.1 and the zonation ZS.4, both compiled by the Italian Group for Defence against Earthquakes (GNDT). The method is validated by comparing the observed and the estimated intensity data points of the Camerino (28/07/1799) and of the Colfiorito (26/09/1997) earthquakes.

scholarly journals Reassessment of the historical seismic activity with major impact on S. Miguel Island (Azores)

2003 ◽  
Vol 3 (6) ◽  
pp. 615-623 ◽  
Author(s):  
D. Silveira ◽  
J. L. Gaspar ◽  
T. Ferreira ◽  
G. Queiroz
Keyword(s):  
Seismic Activity ◽  
Tectonic Setting ◽  
Seismic Intensity ◽  
Historical Period ◽  
Macroseismic Data ◽  
Volcanic Origin ◽  
Eruptive Centre ◽  
Seismic Swarms ◽  
Local Intensity ◽  
Tectonic Origin

Abstract. On account of its tectonic setting, both seismic and volcanic events are frequent in the Azores archipelago. During the historical period earthquakes and seismic swarms of tectonic and/or volcanic origin have struck S. Miguel Island causing a significant number of casualties and severe damages. The information present in historical records made possible a new macroseismic analysis of these major events using the European Macroseismic Scale-1998 (EMS-98). Among the strongest earthquakes of tectonic origin that affected S. Miguel Island, six events were selected for this study. The isoseismal maps drawn for these events enabled the identification of areas characterized by anomalous values of seismic intensity, either positive or negative, to constrain epicentre locations and to identify some new seismogenic areas. Regarding seismic activity associated with volcanic phenomena six cases were also selected. For each of the studied cases cumulative intensity values were assessed for each locality. The distribution of local intensity values shows that the effects are not homogeneous within a certain distance from the eruptive centre, the area of major impacts relates with the eruptive style and damages equivalent to high intensities may occur in Furnas and Sete Cidades calderas. Combining all the historical macroseismic data, a maximum intensity map was produced for S. Miguel Island.

scholarly journals Models of the macroseismic field earthquakes and their influence on seismic hazard assessment values for Central Asia

2020 ◽  
Vol 11 (3) ◽  
pp. 606-623
Author(s):  
T. U. Artikov ◽  
R. S. Ibragimov ◽  
T. L. Ibragimova ◽  
M. A. Mirzaev
Keyword(s):  
Seismic Hazard ◽  
Central Asia ◽  
Hazard Assessment ◽  
Seismic Hazard Assessment ◽  
Seismic Intensity ◽  
Seismic Load ◽  
Macroseismic Data ◽  
Intensity Attenuation ◽  
Macroseismic Field ◽  
Macroseismic Scale

Seismic intensity assessment in points of a macroseismic scale plays an important role for researching the seismic history of areas characterized by active seismicity, as well as for construction (and updating) of seismic zoning maps in various scales. Macroseismic scale points are generally referred to in construction standards applied in the majority of post-Soviet states. In our study aimed to model the macroseismic field of earthquakes, a large volume of macroseismic data on Central Asia was analyzed, and coefficients used in Blake–Shebalin and Covesligeti equations were aligned. This article presents a generalized dependence model of macroseismic intensity attenuation with distance. The model takes into account seismic load features determined by various depths of earthquakes. The ratios of small and big axes of the ellipse, that approximates real isoseists, are estimated with respect to seismic scale points, earthquake depths and magnitudes. The East Uzbekistan area is studied as an example to investigate whether seismic hazard assessment values may differ depending on a chosen law of seismic influence intensity attenuation with distance.

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