scholarly journals Simulation of macroseismic field in Central Greece

1996 ◽  
Vol 39 (5) ◽  
Author(s):  
V. Kouskouna ◽  
S. Chailas ◽  
K. C. Makropoulos ◽  
D. Michalopoulou ◽  
J. Drakopoulos

The distribution of seismic intensity is generally influenced by major geological and tectonic features and, on a smaller scale, by local geological conditions, such as the type of surface soil, the surface-to-bedrock soil structure in sedimentary basins and the depth of the saturated zone, The present paper attempted to determine the distribution of macroseismic intensities based on published attenuation laws in the area of Central Greece, using the epicentral intensity, magnitude, length and direction of fault and a considerable number of observation sites, for which the above mentioned information is available, The expected intensity values were then compared to those observed in the same sites, from four earthquakes in Volos, Central Greece, for which the fault plane solutions are also known. The deviations of the observed values from the theoretical model were then related to the local geological conditions and the corresponding correction factor determined for each site.

2001 ◽  
Vol 34 (4) ◽  
pp. 1425 ◽  
Author(s):  
Β. KOYΣKOYNA

During the period 1941-1980 Thessalia (Eastern Central Greece) experienced a series of strong earthquakes, which caused damage to a large number of localities and to all its major towns. It is therefore characterized an area of moderate-to-high seismicity. In fact, low-to-moderate seismic activity was also observed in the 19th century, and there are a few sources reporting earthquakes in the area even in the centuries before. In the present study a damaging earthquake in the late 19th century is analyzed, in an effort to build up a detailed picture of the event and its supporting data set and to estimate its parameters with recent techniques. The 1892 shock damaged Larissa, situated in central Thessalia, caused minor damage to a few surrounding towns and was felt up to Thessaloniki to the north. The supporting datasets quoting the earthquake are evaluated according to their sources. Two sources reporting the earthquake, not quoted in the existing studies, were also located. In general, the earthquake effects are described in detail in two studies: one contemporary seismological compilation and one seismological compilation 60 years later, both based on contemporary press reports. The analysis is based on the original sources, contemporary to the earthquake. The macroseismic intensities were assessed using the EMS-98 scale and the focal parameters (magnitude, epicentral coordinates, epicentral intensity) were calculated using the Gasperini et al (1997,1999) method. This method allows for the calculation of earthquake parameters even for a limited number of macroseismic intensities, as in this case. The equivalent moment magnitude of the earthquake and the oriented "box", representing the surface projection of the seismogenic fault, were computed through empirical relations. The equivalent moment magnitude was calculated Mw=5.0, using two different empirical relations and the "boxer" technique, which takes into account all the available macroseismic data. The epicentral intensity of the earthquake was assessed to be I0=6-7 at Larisa and the epicentre was located at a close distance (8 km NE of the town). This location has also been proposed by Galanopoulos (1946), based on the assumption that the 1892 event originated from the same source as the 1941 Larisa earthquake. The calculated length of the associated fault was too small to be correlated with existing main tectonic features


1989 ◽  
Vol 1 (1) ◽  
pp. 51-56 ◽  
Author(s):  
V.L. Ivanov

No less than 15–20 sedimentary basins are now known on the Antarctic continental landmass and surrounding continental shelves. Reconstruction of their tectonic and stratigraphic evolution is a specialized task. Owing to the polar position of the continent, the Pacific and Atlantic global geostructures are closely spaced there and the interplay between them is strong enough to result in hybridization of the characteristic tectonic features of the various basins. The present morphostructure of the southern polar region of the Earth is characterized by a prominent circumpolar zoning. Therefore, the sedimentary basins form a gigantic ring along the continental margin, including both the shelf proper and the edge of the continent. Within the ring, the basins are associated with different types of margins successively replacing each other, from the Mesozoic magmatic are in the Pacific segment to the classic passive margin off East Antarctica. The formation of the sedimentary basins in the Antarctic segment of the Pacific mobile belt was a part of a single process of geosynclinal development, whereas on the craton flank the process was superposed on the continental structures by rifting during Gondwana fragmentation. During post-break-up tectonism, continental glaciation played an important part in the formation of the sedimentary basins.


Author(s):  
M. Nurpeissova ◽  
◽  
M. Zh. Bitimbayev ◽  
К. В. Rysbekov ◽  
K. Derbisov ◽  
...  

. Information about copper deposits of Kazakhstan, development of which is carried out in the Saryarka region and its role in the development of the mining industry are considered in the article. Geological, structural and tectonic features of the deposits are presented. Research results on improvement methods of studying and geomechanical processes management in the development of mineral resources are presented. It is shown that the problem of geomechanical processes management can be solved on the basis of methodology for rock condition geomonitoring considered in this article, which provides comprehensive accounting and analysis of all natural and technogenic factors, as well as use of control tools developed by the authors. The article presents technical solutions to ensure operational safety during the development of Saryarka region field reserves, which occur in difficult mining and geological conditions. Ore bodies of the deposit have different sizes and are located at different depths, therefore, seismic surveys are carried out. The geodetic network of provisional seismic surveys at the field has been substantiated. It is proposed to conduct surveys using modern geodetic instruments, such as satellite technologies, electronic, digital geodetic instruments. The geodetic survey methods proposed by the authors provide information on the bowels of the earth with a high degree of accuracy.


2020 ◽  
Vol 177 ◽  
pp. 02005
Author(s):  
Yury Kharin

The article compares engineering and geological conditions in the coastal areas of Vietnam and Tunisia. A sufficiently high similarity of soil structure and their physical and mechanical properties was noted. Both in Vietnam and in Tunisia, foundations for responsible buildings and structures are arranged on bored piles of the same length of 40-60 meters and a diameter of 600 to 1600 mm. The article provides examples of using super-piles of small-size RIT using recharge impulse technology in conditions of weak water-saturated coastal soils of Tunisia. The high efficiency and cost-effectiveness of the new recharge impulse technology were noted. The article presents photographic materials of the test stand for conducting field tests of piles, presents and analyzes the results of testing piles with vertical static load. The low precipitation of the tested piles and their high load-bearing capacity prove the promise of using super-piles of RIT in the conditions of weak soils of Tunisia and, consequently, in the coastal areas of Vietnam.


2017 ◽  
Vol 43 (4) ◽  
pp. 2075
Author(s):  
Ch. K. Karamanos ◽  
V. G. Karakostas ◽  
L. Seeber ◽  
E. E. Papadimitriou ◽  
A.A. Kilias

The December 2008, M=5.2 earthquake occurred in the Voiotikos–Kifissos basin near the town of Amfikleia in Central Greece and was followed by an intense sequence with hundreds of earthquakes. Mainshock source characteristics derived from the recordings of the Greek National Seismological Network are consistent with previous known earthquakes as well as with the current nearly N–S extensional regime. The adequate azimuthal coverage and the calculated time residuals at each seismological station ensure high location accuracy, whereas the stations operated close to the seismic excitations constrained 80% of the focal depths between 8 and 12km. Distances from the mainshock epicenter to the 10 closest seismological stations vary from 15 to 75 km. Hypoinverse and HypoDD were used for locations, and FPFIT was used for fault plane solutions of events with an adequate number of clear first arrivals. The hypocenters and focal mechanisms illuminate a ≈10km–long fault zone striking nearly E–W with oblique normal faulting and a small left lateral component. The Voiotikos–Kifissos basin is bordered in the south by two left–stepping en echelon segments known as the Pavliani fault zone and the Parnassos detachment, which strike NW and dip NE. In our preferred interpretation, the Amfikleia mainshock ruptured a previously recognized south–dipping fault antithetic to the basin border faults. This fault may be associated with the left step on the border fault, which would be releasing if that fault had a sinistral component.


1995 ◽  
Vol 38 (5-6) ◽  
Author(s):  
E. Guidoboni ◽  
G. Ferrari

The authors' aim in the following study is to contribute to the assessment of the seismic hazard of historical cities. From this preliminary analysis the general characteristics of the seismicity affecting Florence and the evaluation of its seismic hazard may be deduced. Florence is a <<mythical>> city of world tourism, and its extraordinary artistic value and its ability to be utilized constitute a great economic resource. From this perspective, the authors have tackled some aspects of its urban features (demography and main building types, successive phases in the growth of the city, etc.), aimed at the pooling of information as a basis for further, more specific analyses of seismic risk. The study is based on a review of 131 seismic events of potential interest for the site of Florence from the 12th century. In the case of each of these earthquakes, it was possible to verify the real seismic effects sustained, and thus to assess the seismic intensity on the site. This also enabled the limits in the application of the standard attenuation laws of to be checked. Of all the earthquakes analyzed. those which caused the greatest effects on the urban area have also been identified: namely, the earthquake of 28 September 1453. and those of 18 May and 6 June 1895, both with Io=VIII MCS. From their overall analysis the authors have further extrapolated the necessary data to statistically evaluate the probabilities of any future earthquake occurring, according to intensity classes.


1976 ◽  
Vol 66 (5) ◽  
pp. 1713-1725
Author(s):  
A. Hedayati ◽  
J. L. Brander ◽  
M. Berberian

abstract A short microearthquake survey of part of north central Iran around the city of Tehran made late in 1974, showed that earthquakes occurred at the rate of 21.37 events per day. Epicentral locations for 37 events, using a geometric ray path technique, show the observed activity to be concentrated in three principal groups: two associated with the known major fault on the south flank of the Alborz mountain, while the third constitutes a previously unrecognized lineation passing very close to the city of Tehran. The cumulative number versus magnitude relation was obtained from the study of 198 well-recorded events. The slope of the linear portion of the relation (b value), −0.79, agrees well with the value of −0.86 determined from the USCGS records of larger earthquakes between 1961 and 1973. Composite fault-plane solutions were made for each of the three principal groups, showing predominantly strike-slip movement with a thrust component on the south of the Alborz and thrusting on the new lineation. The seismic intensity risk curve calculated for the area shows that the city of Tehran can expect ground movement of MM intensity VII every 12 years, and intensity IX every 350 years.


1993 ◽  
Vol 12 (1) ◽  
pp. 25-35 ◽  
Author(s):  
Michele Maugeri ◽  
Ernesto Motta ◽  
Xinchuam Zeng

2012 ◽  
Vol 518-523 ◽  
pp. 2079-2083
Author(s):  
Xu Feng Li ◽  
Feng Hua Shi ◽  
Xiao Feng Jia ◽  
Geng Biao Qiu

The total emission of CO2obviously increased while the GDP rise. And China would become the biggest country on total emission of CO2in future under the International Energy Agency. Demo projects had shown that carbon dioxide geological storage was one kind of tech that useful depositing the CO2under the ground. In China concentrated CO2sources distributed in or around the sedimentary basins which owned suitable geological conditions to storage CO2into underground rock formations. And the storage capacity was large.


2020 ◽  
Vol 2 (2) ◽  
pp. 17-34
Author(s):  
Angela Petruta Constantin ◽  
Elena Florinela Manea ◽  
Iren Adelina Moldovan ◽  
Raluca Partheniu

The aim of the present paper is to test intensity attenuation relationships for subcrustal earthquakes occurred in Vrancea (Romania) seismogenic zone in relation with some important dams situated in extra-Carpathian area. During centuries, the Romanian territory has been shaken by strong earthquakes, most of them being centered within Vrancea Zone, which is situated at the bending area of the South-Eastern Carpathians. Most of the zones from extra-Carpathian area are affected by the subcrustal seismic events, where many hydro-technical structures exist, being also exposed to earthquakes action. A detailed analysis of the intensity attenuation laws developed for subcrustal seismic sources was performed using the most recent and complete intensity datasets. We use an extended and combined intensity data including historical and modern, qualitative and quantitative data, i.e. a number of 11 earthquakes occurred during the period 1738-2009 with epicentral/maximum intensities ranging from VII-X MSK degrees, and magnitude Mw from 5.4 to 7.9. All the input data used for testing are resulted after the reevaluation and evaluation of the macroseismic effects produced by the seismic events included in the present study (8697 IDP). The selected attenuation laws were tested for different values of epicentral intensity and with reference to twelve and twenty four azimuthal directions. Besides the testing of the relationships, isoseismal maps based on the selected attenuation laws were accomplished, associated to the biggest possible earthquake (worst scenario) for the Vrancea subcrustal zone, also highlighting the calculated intensities in the selected dam sites. Brief description of the study and used methods. Brief description of the study and used methods.


Sign in / Sign up

Export Citation Format

Share Document