共查询到20条相似文献，搜索用时 38 毫秒
1.
Mohammad Talebi Abbas Sivandi-Pour Ghasem-Ali Ahmadi Ehsan Noroozinejad Farsangi Shamseddin Esmaeili Mohammad-Javad Banimahdi-Dehkordi Hamidreza Safizadeh Mahdieh Akbarpoor Ehsan Ebrahimi Rabe Sharifi Rad Manoochehr Fallah 《地震科学（英文版）》2022,35(2):122-137
Fault lineaments are the main input data in earthquake engineering and seismology studies. This study presents a digitally-based active fault map of the Kerman region in central-east Iran which experienced several devastating earthquakes on poorly exposed and/or not identified active faults. Using Landsat 8 data, we have carried out the image-based procedures of fault mapping, which include applying the contrast stretching technique, the principal component analysis, the color composite technique, the spectral rationing, and creating the false-color composite images. Besides, we have cross-checked the resulting map with the geological maps provided by the Geological Survey of Iran to decrease the associated uncertainties. The resulting map includes 123 fault segments, still, a part of which has been expressed in the previously compiled active-fault maps of Iran. Indeed, the new one is mapping the poorly exposed active faults, so-called secondary faults, which are able to produce strong events. These faults are primarily associated with poorly defined areas that accommodate low levels of seismicity; however, sporadic strong events are likely to occur. It has also been investigated that these kinds of faults are seismogenic and are able to produce destructive events. In total, the outcome of this study can also be jointed with seismic studies for investigating parts of the earthquake activity in central-east Iran, in particular for the fault-based approaches in impending earthquake-resistant buildings. 相似文献
2.
The effective elastic thickness of the lithosphere has an important role in constraining compositional structure, geothermal gradient and tectonic forces within the lithosphere and the thickness of this layer can be used to evaluate the earthquakes’ focal depth. Hence, assessment of the elastic thickness of the lithosphere by gravitational admittance method in Iran is the main objective of this paper. Although the global geopotential models estimated from the satellite missions and surface data can portray the Earth’s gravity field in high precision and resolution, there are some debates about using them for lithosphere investigations. We used both the terrestrial data which have been provided by NCC (National Cartographic Center of Iran) and BGI (Bureau Gravimetrique International), and the satellite-derived gravity and topography which are generated by EIGEN-GL04C and ETOPO5, respectively. Finally, it is concluded that signal content of the satellite-derived data is as rich as the terrestrial one and it can be used for the determination of the lithosphere bending. 相似文献
3.
4.
Nezihi Canitez 《Pure and Applied Geophysics》1969,75(1):76-87
Summary Data from focal mechanism solutions obtained by different authors and those of 8 fault-plane solutions found in this study have been used to search for the distribution of the main stress axes in Iran. For this purpose, the area has been divided into three regions as southern, central and northern Iran. The results indicate that the characteristics of the motion at the foci are different in each of the three regions. — By examining the B axes in south Iranian earthquakes, direction of tectonic motion has been obtained as N 66°E. Since the maximum and intermediate stress axes are nearly horizontal, it is concluded that focal movements in this region are of reverse fault type. Thus, there is a similarity between recent crustal movements and those occurring during Alpine orogeny which is in the form of an overthrusting to the southwest. — In central Iran earthquakes however, tension is predominant, and, therefore, in this region faultings are dip-slip normal or strike-slip, and the horizontal components of displacements are dextral. The mean direction of maximum tension axes is nearly perpendicular to the central Iranian complexes. — It is deduced from north Iranian shocks that, in this region, the earthquakes studied are of nearly almost pressural type, and horizontal components of the oblique displacements in foci are sinistral. 相似文献
5.
This paper studies one of the most important problems of dry countries that are confronted with water deficit and the competition of rivals to allocate water. Some common methods have been investigated for computing the minimum water requirement to save a river's biological activity. After a discussion of the currently used method in Iran (the Tenant Method), the application of some other methods, which are known as Hydraulic and Hydrological Methods, is illustrated. The case study is a river in the northern part of Iran and this research addresses the critical situation of this river in near future regarding the planned anthropogenic alteration and its consequences. It has been shown that the application of environmental water allocation methods that have no background in a region could be misleading. The first proposed method is the Texas Method, in which flexibility in water allocation helps to develop an integrated river management paradigm in the study area. The second preferred method is a Hydraulic Method, by which the implementation of morphological parameters or flow geometrical properties could sustain physical habitat within an acceptable range in terms of depth, width, velocity, and bed shear stress. In the case study, the Maximum Curvature Method was superior to the Slope Method. The investigation revealed that using a widely recommended slope of 1 for the discharge‐wetted perimeter function can lead to an overestimated and unacceptable discharge. The Tenant Method in respect to minimum environmental flow requirement yielded the weakest result, and it has been illustrated that its application might impose irrecoverable shock to the ecosystem. The Flow Duration Curve Method (the Q95 Method), in spite of its subjectivity, showed more compatibility with the river's condition in comparison with the Tenant Method. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
6.
In present paper, wavelet analysis of total dissolved solid that monitored at Nazlu Chay (northwest of Iran), Tajan (north of Iran), Zayandeh Rud (central of Iran) and Helleh (south of Iran) basins with various climatic conditions, have been studied. Daubechies wavelet at suitable level (db4) has been calculated for TDS of each selected basins. The performance of artificial neural networks (ANN), two different adaptive-neurofuzzy inference system (ANFIS) including ANFIS with grid partition (ANFIS-GP) and ANFIS with subtractive clustering (ANFIS-SC), gene expression programming (GEP), wavelet-ANN, wavelet-ANFIS and wavelet-GEP in predicting TDS of mentioned basins were assessed over a period of 20 years at twelve different hydrometric stations. EC (μmhos/cm), Na (meq L?1) and Cl (meq L?1) parameters were selected (based on Pearson correlation) as input variables to forecast amount of TDS in four studied basins. To develop hybrid wavelet-AI models, the original observed data series was decomposed into sub-time series using Daubechies wavelets at suitable level for each basin. Based on the statistical criteria of correlation coefficient (R), root mean square error (RMSE) and mean absolute error (MAE), the hybrid wavelet-AI models performance were better than single AI models in all basins. A comparison was made between these artificial intelligence approaches which emphasized the superiority of wavelet-GEP over the other intelligent models with amount of RMSE 18.978, 6.774, 9.639 and 318.363 mg/l, in Nazlu Chay, Tajan, Zayandeh Rud and Helleh basins, respectively. 相似文献
7.
The legal regime of the Caspian Sea has been determined under Treaties 1921 and 1940 by and between Iran and former Soviet Union. In fact, we are neither to explain it nor to determine. As understood from the provisions therein, the exploitation and use of the Caspian Sea by both countries are based on the Condominium. However, there is a 10-nautical mile strip as exclusive fishing areas which have been allocated to the states under the 1940 treaty. It means that Soviet Union and Iran may benefit the marine livings resources out of that strip on an equal manner. This right also includes the seabed and underlying bed. So, the legal regime of this sea may be based on a 10-nautical mile exclusive region for all five states and the remaining part as common and joint area under an agreement until an explaining and supervising organization is established to exploit and supervise over living and non-livings resources. 相似文献
8.
Saman Yaghmaei-Sabegh 《地震工程与工程振动(英文版)》2018,17(1):139-148
Macroseismic intensity data plays an important role in the process of seismic hazard analysis as well in developing of reliable earthquake loss models. This paper presents a physical-based model to predict macroseismic intensity attenuation based on 560 intensity data obtained in Iran in the time period 1975–2013. The geometric spreading and energy absorption of seismic waves have been considered in the proposed model. The proposed easy to implement relation describes the intensity simply as a function of moment magnitude, source to site distance and focal depth. The prediction capability of the proposed model is assessed by means of residuals analysis. Prediction results have been compared with those of other intensity prediction models for Italy, Turkey, Iran and central Asia. The results indicate the higher attenuation rate for the study area in distances less than 70 km. 相似文献
9.
M. Pazirandeh 《Bulletin of Volcanology》1973,37(4):573-585
Volcanic rocks in Iran have been subdivided into three geographical groups: a belt extending from Maku district to Bazman, the Alborz Mountains, and East Iran. The average composition of the volcanic rocks is andesitic, although other rock types such as dacite, basalt and alkaline rocks have also been reported. In Iran, as elsewhere, the volcanics can be related to tectonic events (orogenic movements or laulting) and to the modern plate tectonics. 相似文献
10.
Saman Yaghmaei-Sabegh 《Pure and Applied Geophysics》2013,170(4):597-606
The intensity scales in different forms provide valuable information on regional earthquake effects. In this paper, a theoretical model which has been developed recently for seismic intensity estimation is re-examined by employing strong motion records from ten Iranian earthquakes. The analysis results confirmed the capability of the implemented method to estimate the seismic intensity in terms of the MMI scale based on a Fourier spectrum in the study area. The predicted intensity values were compared with another technique utilizing peak ground velocity (PGV) as a predictor. To reveal the high potential of the adopted approach, the theoretical isoseismal map was developed for the 1978 Tabas, Iran earthquake (Mw = 7.4) based on a stochastic finite-fault modelling of ground motions. Results showed good compatibility of predicted intensity values while the historical earthquake records are not enough for a given site. 相似文献
11.
《水文科学杂志》2012,57(1):127-137
ABSTRACTDetermining the catchment design peak flow is crucial in hydrological practice. In this paper, the conceptual rainfall–runoff model EBA4SUB (Event-Based Approach for Small and Ungauged Basins) was applied in six catchments in Iran. The aims were to test EBA4SUB in reconstructing runoff hydrographs for the investigated case studies and to provide a suitable alternative for the review and updating of design peak flow estimation in Iran. The EBA4SUB output was compared with previous studies on selected catchments. The results show, for all case studies, a large variability in the peak flow values; the EBA4SUB model gave flow values similar to the other methodologies. The EBA4SUB model can be recommended for the following reasons: (i) it minimizes the subjectivity of the modeller. (ii) its modules are based on state-of-the-art procedures, which have been appropriately optimized for ungauged basins; and (iii) it furnishes the whole design flood hydrograph. 相似文献
12.
Sedigheh Farahi Ghasre Aboonasr Ahmad Zamani Fatemeh Razavipour Reza Boostani 《Acta Geophysica》2017,65(4):589-605
Producing accurate seismic hazard map and predicting hazardous areas is necessary for risk mitigation strategies. In this paper, a fuzzy logic inference system is utilized to estimate the earthquake potential and seismic zoning of Zagros Orogenic Belt. In addition to the interpretability, fuzzy predictors can capture both nonlinearity and chaotic behavior of data, where the number of data is limited. In this paper, earthquake pattern in the Zagros has been assessed for the intervals of 10 and 50 years using fuzzy rule-based model. The Molchan statistical procedure has been used to show that our forecasting model is reliable. The earthquake hazard maps for this area reveal some remarkable features that cannot be observed on the conventional maps. Regarding our achievements, some areas in the southern (Bandar Abbas), southwestern (Bandar Kangan) and western (Kermanshah) parts of Iran display high earthquake severity even though they are geographically far apart. 相似文献
13.
The catalogue of earthquakes recorded in Iran during 2006–2010 by a dense network of digital telemetric seismic stations is
analyzed. The spectrum of the time series of these earthquakes contains a sharp maximum at 24 h. The corresponding curve of
diurnal periodicity constructed by the superposed epoch method has a clear double-peak maximum near noon(11 a.m.-5 p.m. local
time), which exceeds the level of seismic activity observed during the rest time of the day by a factor of 3-3.5. In the same
time interval, the average hourly magnitudes of seismic events sharply drop from M = 2.15 to M = 1.95. The ratio of the normalized number of earthquakes in the daytime to those at other times of the day, which was determined
within a moving window half a square degree in size, has seven distinct compact spatially isolated maxima whose magnitudes
attain several dozens to a hundred units. These maxima are probably caused by industrial activity, such as road building and
quarry explosions. We also note the presence of the weekend effect when the daytime maximum in the weekly curve of diurnal
variations in seismic activity almost completely disappears on Friday, which is the weekend in Muslim countries. At the same
time, elimination of the supposed noise component from the catalogue by the approved technique changes nothing for the daytime
maximum in the daily pattern of earthquakes in Iran. In order to account for this inconsistency, we suggest invoking additional
information on the technogenic seismicity and considering weak earthquakes induced by quarry explosions and vibrations of
industrial machines, in particular, power units of numerous hydroelectric power stations distributed over the territory of
Iran. 相似文献
14.
The survey of climatic drought trend in Iran 总被引：5，自引：3，他引：2
Hossein Bari Abarghouei Mohammad Amin Asadi Zarch Mohammad Taghi Dastorani Mohammad Reza Kousari Mehdi Safari Zarch 《Stochastic Environmental Research and Risk Assessment (SERRA)》2011,25(6):851-863
Drought is one of the most important natural hazards in Iran. Therefore, drought monitoring has become a point of concern
for most of the researchers. In the present study, the changes and trend of drought was surveyed, under the current global
climate changes, by non parametric Mann–Kendall statistical test for 42 synoptic stations at different places of Iran. Standardized
Precipitation Index (SPI) was calculated to recognize the drought condition at different time scales (3, 6, 9, 12, 18 and
24 months’ time series) for analyzing the drought trend in the recent 30 years. The obtained results have indicated a significant
negative trend of drought in many parts of Iran, especially the South-East, West and South-West regions of the country. According
to the results, although some parts of Iran such as North (around the Caspian Sea) and Northeast show no significant trend
but in other parts of country, the severity of drought has increased during the last 30 years. 相似文献
15.
In recent years, the water demand has been increasing considerably in Bojnourd, capital of Northern Khorasan province in NE of Iran, and the extracted water from Bojnourd alluvial aquifer, with an area of 65 km2, is not sufficient for residents. The required water is going to be supplied from Shirindare dam, located out of Bojnourd aquifer’s catchment area; therefore, the groundwater levels will rise in some parts of the aquifer, due to the return flow of supplied water, which will cause serious problems for the city. In this paper, the groundwater flow system of Bojnourd aquifer has been numerically simulated using MODFLOW code in GMS interface. The model, primarily, was calibrated for a steady state condition for the mean values of oneyear period (Sep. 2009 to Sep. 2010) which has a steady condition with low stresses on the aquifer. Then the model was run/calibrated for transient conditions for a two year period (Sep. 2007 to Sep. 2009). After determining the hydraulic properties of the aquifer and confirming their validity, different management scenarios, were applied to the model. Results reveal that groundwater levels in the urban area will rise by over 3 m, by infiltrating 40% of supplied water from the Shirindare dam into the aquifer. To manage the rising water levels, two different management scenarios were applied to the aquifer model. In doing so and with proper management of aquifer exploitation during critical situations, not only will the groundwater level drop; also the city of Bojnourd can develop urban landscaping by constructing sports/cultural camping area using the extra pumped water. 相似文献
16.
Hamed Azizi-Bondarabadi Nuno Mendes Paulo B. Lourenço Neda H. Sadeghi 《Bulletin of Earthquake Engineering》2016,14(11):3195-3229
School facilities in Iran, in particular masonry schools, have shown poor performance during past earthquakes and can be identified as one of the parts of the country’s infrastructure that is most vulnerable to earthquakes. Hence, in this paper a method to perform index-based damage assessment for brick masonry schools located in the province of Yazd, the central region of Iran, using a comprehensive database of school buildings, is proposed. The database was obtained from the field survey forms applied for each observed school to collect the features of and damage to the structure. The results of a vulnerability index method developed in Iran are employed as input data to obtain empirical fragility curves for the school inventory. The Macroseismic model and GNDT II level method are two empirical methods combined in this procedure. Finally, the procedure is verified using damage survey data obtained after recent earthquakes (1990 Manjil–Rudbar earthquake and 2003 Bam earthquake) that occurred in Iran. 相似文献
17.
Nader Davoudi Hamid Reza Tavakoli Mehdi Zare Abdollah Jalilian 《Acta Geophysica》2018,66(6):1359-1373
The main goal of this article is to decluster Iranian plateau seismic catalog by the epidemic-type aftershock sequence (ETAS) model and compare the results with some older methods. For this purpose, Iranian plateau bounded in 24°–42°N and 43°–66°E is subdivided into three major tectonic zones: (1) North of Iran (2) Zagros (3) East of Iran. The extracted earthquake catalog had a total of 6034 earthquakes (Mw?>?4) in the time span 1983–2017. The ETAS model is an accepted stochastic approach for seismic evaluation and declustering earthquake catalogs. However, this model has not yet been used to decluster the seismic catalog of Iran. Until now, traditional methods like the Gardner and Knopoff space–time window method and the Reasenberg link-based method have been used in most studies for declustering Iran earthquake catalog. Finally, the results of declustering by the ETAS model are compared with result of Gardner and Knopoff (Bull Seismol Soc Am 64(5):1363–1367, 1974), Uhrhammer (Earthq Notes 57(1):21, 1986), Gruenthal (pers. comm.) and Reasenberg (Geophys Res 90:5479–5495, 1985) declustering methods. The overall conclusion is difficult, but the results confirm the high ability of the ETAS model for declustering Iranian earthquake catalog. Use of the ETAS model is still in its early steps in Iranian seismological researches, and more parametric studies are needed. 相似文献
18.
For the first time, we present the variation of crust–mantle boundary beneath the northeast Iran continental collision zone
which is genetically part of the Alpine–Himalayan orogeny and beneath Central Iran which is a less-deformed tectonic block.
The boundary was imaged by stacking teleseismic P–S converted phases and shows a strong variation of Moho from 27.5 km under
Central Iran to 55.5 km beneath the Binalud foreland basin. The thickest crust is not located beneath the high topography
of the Kopeh Dagh and Binalud mountain ranges suggesting that these mountain ranges are not supported by a crustal root. The
simple gravity modeling of the Bouguer anomaly supports this idea. 相似文献
19.
A Geographic Information System‐based site selection experience for the construction of a geomagnetic observatory in Kerman Province,Iran 
下载免费PDF全文
下载免费PDF全文 Marjan Izadi Yazdanabadi Azadeh Hojat Hojjatollah Ranjbar Saeed Karimi Nasab 《Geophysical Prospecting》2017,65(Z1):237-245
In recent years, the necessity of constructing new geomagnetic observatories in Iran has been discussed from various aspects. Improper site selection of such important data centres can significantly affect the quality of their recorded data. In this research, site selection studies were performed to find the most favourable location to construct a geomagnetic observatory in Kerman Province, southeast of Iran. Having defined 11 site selection criteria for geomagnetic observatories, all the data layers were prepared for the whole province. After detection of seven promising regions using analytical hierarchy process and fuzzy logic method in geographical information system, Technique for Order of Preference by Similarity to Ideal Solution was used for ranking of the suitable areas. The most favourable region was finally detected southwest of Kerman Province, located between the cities of Baft and Sirjan. Detailed land surveys can be focused in this region to decide on the optimum area for the construction of the geomagnetic observatory. 相似文献
20.
The effective elastic thickness, Te, has been calculated in the collision zone between Arabia and Eurasia in Iran from the wavelet coherence. The wavelet coherence is calculated from Bouguer anomalies and topography data using the isotropic fan wavelet method, and gives Te values between 14.2 and 62.2 km. The lower value is found in the Central Iranian Blocks and the East Iranian Belt which are bounded by several large strike-slip faults with lithospheric origin. The higher value occurs in the east of the South Caspian Sea Basin. The resulting Te map shows positive and negative correlation with shear wave velocity and surface heat flow, respectively. A comparison between the seismogenic thickness (Ts) and Te in Iran suggests that Te > Ts. Results of the load ratio in Iran indicate that in most of the study area surface loads are much more prevalent than subsurface loads, except in the Central Iranian Blocks and NW of Iran. Intermediate to low Te values in Iran were inherited from multiple rifting and orogenic activities from Late Precambrian (∼650 Ma) to present day which are not only reflected in thin and warm lithosphere but also an increasing seismicity rate. 相似文献