scholarly journals FITTING AN ELLIPSE TO THE SET OF INTENSITY DATA POINTS OF VRANCEA EARTHQUAKES

2016 ◽  
Vol 20 (4) ◽  
Author(s):  
RASHID BURTIEV
Keyword(s):  
Intensity Data ◽  
Macroseismic Field ◽  
Vrancea Earthquakes ◽  
Test Criteria ◽  
Data Points ◽  
Set Of Points ◽  
Intensity Data Points

<p>Fitting an ellipse to the set of intensity data points of earthquakes occurred on 11.10.1940, 07.04.1977, 31.08.1986, 30.05.1990 and 31.05.1990 is performed. Test criteria indicate that the ellipse smoothes the observed line of macroseismic field. For all earthquakes, focal axes of 5, 6 and 7 EMS-98 intensity zones are directed along the y-axis. For other zones are oriented along the parallels. This fact is one more acknowledgement of the anisotropy of a geophysical medium. Approximation of the set of points with an ellipse is performed using the method proposed by Fitzgibbon. </p>

scholarly journals Re-evaluation of the macroseismic effects produced by the March 4, 1977, strong Vrancea earthquake in Romanian territory

2013 ◽  
Vol 56 (1) ◽  
Author(s):  
Aurelian Pantea ◽  
Angela Petruta Constantin
Keyword(s):  
Seismic Event ◽  
Seismic Intensity ◽  
Intensity Data ◽  
Large Area ◽  
Macroseismic Field ◽  
Vrancea Zone ◽  
Macroseismic Effects ◽  
Data Points ◽  
Intensity Data Points ◽  
Seismic Intensity Scale

<p>In this paper, the macroseismic effects of the subcrustal earthquake in Vrancea (Romania) that occurred on March 4, 1977, have been re-evaluated. This was the second strongest seismic event that occurred in this area during the twentieth century, following the event that happened on November 10, 1940. It is thus of importance for our understanding of the seismicity of the Vrancea zone. The earthquake was felt over a large area, which included the territories of the neighboring states, and it produced major damage. Due to its effects, macroseismic studies were developed by Romanian researchers soon after its occurrence, with foreign scientists also involved, such as Medvedev, the founder of the Medvedev-Sponheuer-Karnik (MSK) seismic intensity scale. The original macroseismic questionnaires were re-examined, to take into account the recommendations for intensity assessments according to the MSK-64 macroseismic scale used in Romania. After the re-evaluation of the macroseismic field of this earthquake, the intensity dataset was obtained for 1,620 sites in Romanian territory. The re-evaluation was necessary as it has confirmed that the previous macroseismic map was underestimated. On this new map, only the intensity data points are plotted, without tracing the isoseismals.</p>

Macroseismic survey of the 6 February 2016 KwaZulu-Natal, South Africa earthquake

2021 ◽  
Author(s):  
V. Mapuranga ◽  
A. Kijko ◽  
I. Saunders ◽  
A. Singh ◽  
M. Singh ◽  
...  
Keyword(s):  
Structural Damage ◽  
Low Cost ◽  
The United States ◽  
United States Geological Survey ◽  
Intensity Data ◽  
Eastern Cape ◽  
Kwazulu Natal ◽  
Data Points ◽  
Macroseismic Survey ◽  
Intensity Data Points

Abstract On the 6th of February 2016 at 11:00 hours local time (0900 UTC), KwaZulu-Natal was struck by an earthquake of local magnitude ML=3.8. The epicentre of the earthquake was located offshore in the Durban Basin. The earthquake shaking was widely felt within the province as well as in East London in the Eastern Cape province and was reported by various national media outlets. Minor structural damage was reported. A macroseismic survey using questionnaires was conducted by the Council for Geoscience (CGS) in collaboration with the University of KwaZulu-Natal (UKZN) which yielded 41 intensity data points. Additional intensity data points were obtained from the United States Geological Survey (USGS) Did You Feel It? programme. An attempt was made to define a local intensity attenuation model. Generally, the earthquake was more strongly felt in low-cost housing neighbourhoods than in more affluent suburbs.

scholarly journals The autumn 1919 Torremendo (Jacarilla) earthquake series (SE Spain)

2015 ◽  
Vol 58 (3) ◽  
Author(s):  
Josep Batlló ◽  
José Manuel Martínez-Solares ◽  
Ramon Macià ◽  
Daniel Stich ◽  
José Morales ◽  
...  
Keyword(s):  
Intensity Data ◽  
Similar Magnitude ◽  
Se Spain ◽  
Regional Seismicity ◽  
Earthquake Series ◽  
Data Points ◽  
Instrumental Recording ◽  
Definition Of ◽  
Intensity Data Points ◽  
Macroseismic Information

<p>On 10th September 1919 several slightly damaging earthquakes struck the towns of Torremendo, Jacarilla (near Alicante, SE-Spain) and others nearby. Available magnitude estimations for the largest two events of the series are M = 5 approx. They were earthquakes of moderate size and they occurred in a region where similar magnitude earthquakes, thoroughly studied, occurred recently (1999 Mula; 2002 Bullas; 2005 La Paca; 2011 Lorca). This makes these events of interest for a better definition of the regional seismicity. We study their sources from the analysis of the available contemporary seismograms and related documents. A total of 23 seismograms from 9 seismic stations have been collected and digitized. These seismograms contain records for the two main events and several aftershocks of the earthquake series. Finally 44 files, corresponding to 44 recorded single component records from the different events have been processed. The events have been relocated and their magnitudes recalculated. Also, original macroseismic information for these events was recovered. A macroseismic evaluation of the series has been performed. Intensity data points have been recalculated and macroseismic location and magnitude obtained. We conclude that these are the largest earthquakes occurred in the region since the beginning of instrumental recording, with Mw = 5.5 for the largest shock, and that the available data could be compatible with a thrust mechanism related to blind faults in the Bajo Segura region.</p>

scholarly journals Intensity-distance attenuation laws for the Portugal mainland using intensity data points

2014 ◽  
Vol 199 (2) ◽  
pp. 1278-1285 ◽  
Author(s):  
Boris Le Goff ◽  
José Fernando Borges ◽  
Mourad Bezzeghoud
Keyword(s):  
Intensity Data ◽  
Data Points ◽  
Intensity Data Points ◽  
Attenuation Laws

scholarly journals The 1895 Ljubljana earthquake: can the intensity data points discriminate which one of the nearby faults was the causative one?

2018 ◽  
Vol 22 (4) ◽  
pp. 927-941
Author(s):  
Lara Tiberi ◽  
Giovanni Costa ◽  
Petra Jamšek Rupnik ◽  
Ina Cecić ◽  
Peter Suhadolc
Keyword(s):  
Intensity Data ◽  
Data Points ◽  
Intensity Data Points

scholarly journals Reappraisal of the 1863 Huércal-Overa Earthquake (Betic Cordillera, SE Spain) by the Analysis of ESI-07 Environmental Effects and Building Oriented Damage

Geosciences ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 303
Author(s):  
Pablo G. Silva ◽  
Javier Elez ◽  
Jorge L. Giner-Robles ◽  
Raúl Pérez-López ◽  
Elvira Roquero ◽  
...  
Keyword(s):  
Environmental Effects ◽  
Local Maximum ◽  
Seismic Intensity ◽  
Maximum Intensity ◽  
Intensity Data ◽  
Se Spain ◽  
Epicentral Area ◽  
Data Points ◽  
Definition Of ◽  
Intensity Data Points

This work reviews the 1863 Huércal-Overa earthquake (VI-VII EMS) based on the environmental seismic intensity scale (ESI-07) and oriented archaeoseismological building damage. The performed analysis identifies 23 environmental effects (EEEs) and 11 archaeoseismological effects (EAEs), completing a total of 34 intensity data-points within the intensity zone ≥ VI EMS. The new ESI intensity data quintuplicate the previous intensity data-points ≥ VI EMS (five localities) for this event. Sixteen of the identified EEEs indicate the occurrence of intensity VII-VIII within the Almanzora valley, south of Huércal-Overa, over an area of ca. 12–15 km2. Anomalies in water bodies, slope movements, hydrogeological anomalies, ground cracking, and other effects (gas emissions, tree shaking) are the more diagnostic EEEs—with one of them indicating a local maximum intensity of VIII-IX ESI-07 (Alboraija lake). Environmental earthquake damage of intensity ≥ VI covers an area of c. 100 km2, compatible with a VIII ESI intensity event. The spatial distribution of EEEs and EAEs indicates that the zone of Almanzora River Gorge, which was depopulated during the earthquake epoch, was the epicentral area, and compatible with seismotectonic data from active shallow blind thrusting beneath the Almagro Range. The use of ESI data in nearly unpopulated areas help to fill gaps between damaged localities (EMS data) multiplying intensity data-points, providing a better definition of the intensity zones and offering a geological basis to look for suspect seismic sources.

Historical Earthquakes: New Intensity Data Points Using Complementary Data from Churches and Monasteries

2018 ◽  
pp. 103-116
Author(s):  
Gheorghe Marmureanu ◽  
Radu Vacareanu ◽  
Carmen Ortanza Cioflan ◽  
Constantin Ionescu ◽  
Dragos Toma-Danila
Keyword(s):  
Historical Earthquakes ◽  
Intensity Data ◽  
Data Points ◽  
Intensity Data Points

scholarly journals Culling a Set of Points for Roundness or Cylindricity Evaluations

2003 ◽  
Vol 13 (03) ◽  
pp. 231-240 ◽  
Author(s):  
Olivier Devillers ◽  
Franco P. Preparata
Keyword(s):  
Cross Sections ◽  
Input Data ◽  
Linear Time ◽  
Programming Approach ◽  
Fixed Size ◽  
Recent Approach ◽  
Data Points ◽  
Surface Measurements ◽  
Computational Metrology ◽  
Set Of Points

Roundness and cylindricity evaluations are among the most important problems in computational metrology, and are based on sets of surface measurements (input data points). A recent approach to such evaluations is based on a linear-programming approach yielding a rapidly converging solution. Such a solution is determined by a fixed-size subset of a large input set. With the intent to simplify the main computational task, it appears desirable to cull from the input any point that cannot provably define the solution. In this note we present an analysis and an efficient solution to the problem of culling the input set. For input data points arranged in cross-sections under mild conditions of uniformity, this algorithm runs in linear time.

Global Energy Fairing of B-Spline Curves in Path Planning Problems

2007 ◽  
Author(s):  
Alexander V. Pesterev ◽  
Lev B. Rapoport ◽  
Ruslan F. Gilimyanov
Keyword(s):  
Path Planning ◽  
Original Data ◽  
Moving Vehicle ◽  
B Spline ◽  
Spline Curves ◽  
Data Points ◽  
Set Of Points ◽  
First Time ◽  
Planning Problems ◽  
Third Derivative

The paper is concerned with path planning for mobile robots. Specifically, the discussion is related to the following problem: Given an ordered sequence of points on the plane, construct a path that fits these points and satisfies certain smoothness requirements. These requirements may be different in different problems and imply basically that the constructed path is to be realizable. Such a problem arises, e.g., when it is required to follow in an automated mode a path stored as a discrete set of points, which, e.g., were collected by a GPS receiver installed on a car when it followed this path for the first time. Due to errors inherent in the data points, the shape of the curve approximating the desired path turns out often inappropriate. The shape of the curve can be improved by applying the so-called fairing, which consists in moving the original data points with the aim to minimize some fairness criterion. Adequate small variations of the data points preserve the proximity of the resulting path to the original data points and make it fairer. In the paper, a new global fairing method is proposed. It reduces the problem of constructing a fair cubic B-spline curve to solving a quadratic programming problem with simple constraints. The fairing criterion is based on minimizing jumps of the spline third derivative. The discussion is illustrated by numerical examples of fairing two actual paths constructed by data points collected by a GPS/GLONASS receiver mounted on a moving vehicle.

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