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Javad Ashjari Mojtaba Noori Reza Azimi Mohammad Nakhaei 《Arabian Journal of Geosciences》2016,9(3):227
Hydrogeologically, faults may impede, conduit, exert no influence, or may play a combination of these roles on groundwater flow. The object of this paper is to study the hydrogeological role of the Tabarteh fault, which is located on the border of Zagros and Central Iran tectonic zones in an alluvial aquifer. The recorded data of water table levels, chemical parameters, and discharge rate of wells, in addition to geological maps and geophysical results, were collected and evaluated. The outcrop of travertine in limited areas and the emergence of a few small springs within the alluvium show a barrier role of the fault in the groundwater flow. The spatial analysis of chemical components, head time series, and groundwater flow direction assessment demonstrated that the fault acts as both a barrier and a non-barrier in different sections. The multivariate statistical methods of cluster and discriminant analyses also confirm the dual role of the fault. 相似文献
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Monitoring and prediction of land use/land cover changes using CA-Markov model: a case study of Ravansar County in Iran 总被引：1，自引：0，他引：1
Hazhir Karimi Javad Jafarnezhad Jabbar Khaledi Parisa Ahmadi 《Arabian Journal of Geosciences》2018,11(19):592
Human‐induced land use/land cover (LULC) changes are among the most important processes that shape the dynamics of the earth’s surface. This phenomenon, which is occurring at an astonishing rate, and its consequential environmental impacts have become an important area of research for scientists.Therefore, a wide range of methods and models have been developed to detect and predict these alterations, among which cellular automata (CA) models such as the CA‐Markov model, due to their affinity to geographic information system (GIS) and remote sensing (RS), are appropriate for detailed resolution modelling and simulating dynamic spatial processes. In Iran, the district of Ravansar has undergone severe LULC changes recently, thus to take the necessary precautions, decision‐makers need to predict and determine the extent of these changes. In this study, using spatial analysis methods the LULC changes in Ravansar were investigated from 1992 to 2015. Subsequently, the CA‐Markov model was applied to simulate the spatial pattern changes of LULC until 2030. Our results indicated that from 1992 to 2015, this region has witnessed a noticeable increase in the areas of the built‐up and agricultural lands (both aquatic and non‐aquatic), resulting in the decrease of the gardens, range, and bare lands. The simulated LULC map showed that this trend will continue due to more urbanization and development of agricultural areas. 相似文献
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Javad Mehdipour Ghazi Mohssen Moazzen Mohammad Rahgoshay Hadi Shafaii Moghadam 《Journal of Geodynamics》2010,49(5):261-270
The peridotites from north of the town of Nain in central Iran consist of clinopyroxene-bearing harzburgite and lherzolite with small lenses of dunite and chromitite pods. The lherzolite contains aluminous spinel with a Cr number (Cr# = Cr/[Cr + Al]) of 0.17. The Cr number of spinels in harzburgite and chromitite is 0.38–0.42 and 0.62, respectively. This shows that the lherzolite and harzburgite resulted from <18% of partial melting of the source materials. The estimated temperature is 1100 ± 200 °C for peridotites, the estimated pressure is <15 ± 2.3 kbar for harzburgites and >16 ± 2.3 kbar for lherzolites and estimated fo2 is 10?1±0.5 for peridotites. Discriminant geochemical diagrams based on mineral chemistry of harzburgites indicate a supra-subduction zone (SSZ) to mid-oceanic ridge (MOR) setting for these rocks. On the basis of their Cr#, the harzburgite and lherzolite spinels are analogous to those from abyssal peridotites and oceanic ophiolites, whereas the chromites in the chromitite (on the basis of Cr# and boninitic nature of parental melts) resemble those from SSZ ophiolitic sequences. Therefore, the Nain ophiolite complex most likely originated in an oceanic crust related to supra-subduction zone, i.e. back arc basin. Field observations and mineral chemistry of the Nain peridotites, indicating the suture between the central Iran micro-continent (CIM) block and the Sanandaj–Sirjan zone, show that these peridotites mark the site of the Nain–Baft seaway, which opened with a slow rate of ocean-floor spreading behind the Mesozoic arc of the Sanandaj–Sirjan zone as a result of change of Neo Tethyan subduction régime during middle Cretaceous. 相似文献
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Mostafa Moradi Dashtpagerdi Seyed Javad Sadatinejad Rafat Zare Bidaki Ehsan Khorsandi 《Journal of the Indian Society of Remote Sensing》2014,42(1):179-186
In this paper, remote sensing and GIS have been used to assess the status of NO2 at the south west of Iran. 221 data about concentration of NO2 was extracted from Ozone Monitoring Instrument. Ordinary kriging and inverse distance weighting interpolation methods was used to interpolate data. Results showed that ordinary kriging method using cross-validation have had less error. North east of the study area has the highest concentration of NO2 (329 molecule/cm2) and the concentration of NO2 decreases from north east to South west of the study area. On the other hand, data trend results showed that the data seems to exhibit a fairly strong trend in the east west direction and a weaker one in the north–south direction. 相似文献
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An integrated geological-petrophysical analysis of the rudist-bearing sequence of the Cretaceous Sarvak Formation is given one giant oilfield, and provides an improved understanding of this main reservoir in the Abadan Plain, in the Zagros Basin, SW Iran. The main objective of this study is to evaluate reservoir potential of the Sarvak Formation, and then to utilize the calibrated well log signature to correlate reservoir potential in un-cored wells. Eight main facies are recognized and categori... 相似文献
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Moosavi Seyed Amin Bakhtiari Hesam Aloki Honarmand Javad 《Geotechnical and Geological Engineering》2022,40(6):3225-3244
Geotechnical and Geological Engineering - This study examined the petrographically classification, petrological and petrophysical characteristics by taking a vast range of carbonate reservoir rock... 相似文献
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Probabilistic analysis of extreme regional meteorological droughts by L-moments in a semi-arid environment 总被引：1，自引：1，他引：0
Regional extreme value analyses of drought characteristics provide information on probabilistic nature of drought occurrence, viewed as an essential tool in drought mitigation and planning. In this paper, L-moments are used to investigate the regional characteristics and probabilistic behavior of drought severity levels, represented by the Standardized Precipitation Index (SPI) annual minima (the minimum monthly SPI value). Rainfall data of 3, 6, 12, and 24 month time scales are investigated. A regional watershed in southwestern Iran is used as a case study area. The semi-arid nature of the study area requires appropriate selection of rainfall data. The boxplot approach is used to select those months with adequate data time series for the SPI analysis. Appropriateness of the suggested data time series is discussed in the context of the research by Wu et al. (2007). Based on the results, all of the suggested time scales are found appropriate for SPI investigations. For each time scale of interest regional homogeneity is evaluated and the best regional/sub-regional probability distribution function is selected. Regional quantiles are estimated for different time scales and their variability with respect to return period is discussed. 相似文献
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Neda Khanmohammadi Hossein Rezaie Majid Montaseri Javad Behmanesh 《Environmental Earth Sciences》2017,76(15):540
Temporal changes of meteorological variables can affect reference evapotranspiration (ET0). The goal of the present research is to analyze the changes of ET0 and identify the impact of effective meteorological parameters to the changes of ET0. For this purpose, daily meteorological data recorded in 30 synoptic stations of Iran during 1960–2014 were used. The annual and seasonal values of ET0 were calculated by the recorded data. To calculate ET0, FAO56 Penman–Monteith method (standard method) was used. The annual and seasonal trends of ET0 and its eight effective parameters were analyzed. Then the contributions of effective parameters changes on ET0 were determined. To analyze ET0 trend at annual and seasonal scales, two common methods, Spearman’s Rho and Mann–Kendall tests, were used. The R 2 = 0.99 showed that the results of the mentioned methods were similar and on the basis of T-statistic <0.057, their difference was not significant (95% confidence level). Therefore, only one method’s results (Spearman’s Rho) were reported. On the basis of Spearman’s Rho results, the annual and seasonal values of ET0 had negative trend in most of arid and semi-arid stations while the trend of this parameter was positive in humid and very humid stations. At annual and seasonal scales, decreasing in wind speed (W), temperature (T), sunshine hours (n), minimum temperature (TN), dew point temperature (TD), maximum temperature (TX), saturation vapor pressure deficit (SVPD) and solar radiation (RS) was observed in 58, 54, 39, 43, 56, 65, 65 and 37% studied stations, respectively. In many scales, the results showed that TX and W were the most effective meteorological variables on ET0 changes and then SVPD was located in second step in arid and semi-arid stations. In humid and very humid stations, W was the first effective parameter at all scales, except autumn. 相似文献