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

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 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>

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

Estimation of the Parameters of Historical Earthquakes with a New Attenuation Equation in Yunnan Province, China

2020 ◽  
Vol 91 (5) ◽  
pp. 2651-2661 ◽  
Author(s):  
Guoliang Lin ◽  
Jian Wang
Keyword(s):  
Yunnan Province ◽  
Hazard Analysis ◽  
Source Parameters ◽  
Historical Earthquakes ◽  
Intensity Data ◽  
Earthquake Parameters ◽  
Intensity Attenuation ◽  
Earthquake Source Parameters ◽  
Data Points ◽  
Optimal Intensity

Abstract Yunnan Province is in southwest China, where the seismicity has been active since ancient times. Generally, the uncertainty of historical earthquake parameters is larger. To amend the parameters of historical earthquakes, we have developed a new intensity attenuation equation. From 2000 to 2018, there were 25 instrumentally recorded earthquakes with Ms 5.0–6.6 in Yunnan. The parameters of those earthquake events, including their epicentral locations and magnitudes, are determined with high accuracy. Meanwhile, total intensity values of 1345 intensity data points have been carefully assessed by survey. With both accurate earthquake parameters and valuable intensity data, a new intensity attenuation equation has been established. The result shows the optimal intensity magnitude MI can be calculated from the mean of Mi=(I−2.1113+0.0412Δi+1.3717lgΔi)/1.1641, in which Δi is the distance between the epicenter and the surveyed seismic point. By adapting the method proposed by Bakun and Wentworth (1997) for determining earthquake source parameters directly from historical intensity data, we have tested retrospectively the new attenuation on the 25 instrumentally recorded earthquakes. Then this attenuation was applied to deal with the parameters of two historical earthquakes, the 26 February 1713 Xundian earthquake and the 11 May 1909 Huaning earthquakes. Our results reduced the uncertainty of previously estimated parameters, which were large. The amended parameters will be valuable for seismic hazard analysis and earthquake disaster reduction.

Direct phase determination in electron crystallography: small organic molecules

1992 ◽  
Vol 50 (2) ◽  
pp. 1166-1167
Author(s):  
Douglas L. Dorset
Keyword(s):  
Organic Molecules ◽  
Data Sets ◽  
Temperature Structure ◽  
3D Analysis ◽  
Intensity Data ◽  
Electron Crystallography ◽  
Phase Determination ◽  
Measured Intensity ◽  
3D Data

The quantitative use of electron diffraction intensity data for the determination of crystal structures represents the pioneering achievement in the electron crystallography of organic molecules, an effort largely begun by B. K. Vainshtein and his co-workers. However, despite numerous representative structure analyses yielding results consistent with X-ray determination, this entire effort was viewed with considerable mistrust by many crystallographers. This was no doubt due to the rather high crystallographic R-factors reported for some structures and, more importantly, the failure to convince many skeptics that the measured intensity data were adequate for ab initio structure determinations.We have recently demonstrated the utility of these data sets for structure analyses by direct phase determination based on the probabilistic estimate of three- and four-phase structure invariant sums. Examples include the structure of diketopiperazine using Vainshtein's 3D data, a similar 3D analysis of the room temperature structure of thiourea, and a zonal determination of the urea structure, the latter also based on data collected by the Moscow group.

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