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1.
The Khoshk River passes through Shiraz City, southwest Iran. It passes through the populated urban area of Shiraz and receives and carries different kinds of industrial and urban solid and liquid wastes produced by industries and domestic sewage. The obje… 相似文献
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B. Sari Sarraf A. A. Rasouli GH. H. Mohammadi A. Hoseini Sadr 《Arabian Journal of Geosciences》2016,9(10):563
In order to examine the seasonal characteristics of the dust events over western parts of Iran, surface observations from 27 meteorological stations for the period 1951–2014 were analyzed to obtain spatial distributions and temporal variations and trend of dusty day frequency (DDF). Trends of DDF were analyzed by Mann–Kendall and Sen’s estimator of slope nonparametric statistics. Three meteorological stations were selected in north (Tabriz), middle (Kermanshah), and south of the study area (Ahwaz) as reference stations for detecting the regional differences of DDFs. The results showed that DDF is a variable season by season but in general, DDF increases from north to south and from east to west of Iran. The maximum of DDF is monitored in May, June, and July. There are tangible seasonal increasing–decreasing periods in which these changes are logically related with seasonal changes. Regardless of the existence of the maximum DDF in south and southwest of study area, the most intensive increasing DDF trend is calculated in west middle areas. The most widespread and intensive increasing DDF pattern in west of Iran is observed when it is spring. In this case, the dust storms replaced the rainfalls. Distance from dust sources, major movement ways of dust transporting synoptic systems, regional effective wind activity (such as Shamal wind), and arrangement of high mountains are the known factors affecting frequency variation, distribution, and rate of the trend of all the dust phenomena in west of Iran. 相似文献
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Fatemeh Hadavi Marziyeh Notghi Moghaddam Hoda Mousazadeh 《Arabian Journal of Geosciences》2010,3(2):133-139
The aim of this study is to determine calcareous nannofossil species found in Kamar-Kuh area and demonstrate this use for biostratigraphic studies. The Qom Formation is widely distributed in Kamar-Kuh section and has nine members(a–f). In this study, 12 samples were taken and prepared with smear slide. Some of the determined species are listed below, and some of them are photographed by light and scanning microscope. According to obtained nannofossils, 16 species, nine genera, and six families were determined. Obtained nannofossils indicated age of Burdigalian–Serravalian (middle Miocene) for this section. 相似文献
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M. Alipour A. Sheykhan 《International Journal of Environmental Science and Technology》2017,14(1):193-210
Hydrogen combined with fuel cell (FC) technology has been widely discussed as a long-term fuel option to address environmental and energy security concerns. Iran, despite outlining a long-term plan to develop its renewable energies’ (REs) infrastructures, is faced with difficulties in deploying fuel cell hydrogen (FCH). These obstacles—led by lack of adequate funding—have caused a slowdown in the government-driven initiatives in recent years, thus resulting in projects delays and suspensions. This paper focuses on current status of Iran’s FCH within and among leading and neighboring countries. Barriers and challenges of the three main actors (government, university, and industry) on Iran’s FCH development are analyzed and then supported with a policy perspective. It is shown that the government obligations play a significant role to overcome these obstacles and also act as the main driving force to perform the required actions. The paper also proposes strategic measures in a short-, medium-, and long-term framework to promote the technology in Iran in hopes of a clear national policy and a proper vision. It is shown that the responsibility for the short- and medium-term actions lies predominantly upon the government while it will be fully devolved to the private sector in the long term. 相似文献
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Peter J. Dillon Shaun A. Watmough Katya Epova Hayla E. Evans 《中国地球化学学报》2006,25(B08):156-156
In this study, the size of the metal pools and the fluxes between the pools of eight trace metals （Cu, Ni, Zn, Pb, Cd, A1, Mn, Fe） were measured in a small, oligotrophic, dilute lake located in south-central Ontario, Canada. The lake （Plastic Lake） and its catchment have been affected by acid deposition and have been studied since 1979. Limited data were collected for a number of other elements including, V, Cr, Co, As, Rb, Sr, T1, Bi, U and Se and isotope budgets for a few metals （e.g. Pb） were determined. Measurements were available for the sediments, the lake itself, and the wetland and upland portions of the catchment, and thus individual budgets for all compartments could be constructed. These budgets provided information regarding the relative importance of atmospheric inputs versus mobilization from lithogenic sources. In addition, the effects of acid deposition and dissolved organic matter （DOM） on contaminant storage and transfer were investigated. Results indicate that elements such as Pb and V have largely an atmospheric source whereas Cu, Zn, A1 and Fe are primarily derived from the catchment. 相似文献
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Please?refer?to?the?attachment(s)?for?more?details. 相似文献
8.
The Darreh Sary metapelitic rocks are located in the northeast of Zagros orogenic belt and Sanandaj-Sirjan structural zone. The lithological composition of these rocks includes slate, phyllite, muscovitebiotite schist, garnet schist, staurolite-garnet schist and staurolite schist. The shale is the protolith of these metamorphic rocks, which was originated from the continental island arc tectonic setting and has been subjected to processes of Zagros orogeny. The deformation mechanisms in these rocks include bulging recrystallization (BLG), subgrain rotation recrystallization (SGR) and grain boundary migration recrystallization (GBM), which are considered as the key to estimate the deformation temperature of the rocks. The estimated ranges of deformation temperature and depth in these rocks show the temperatures of 275–375, 375–500, and >500°C and the depths of 10 to 17 km. The observed structures in these rocks such as faults, fractures and folds, often with the NW-SE direction coordinate with the structural trends of Zagros orogenic belt structures. The S-C mylonite fabrics is observed in these rocks with other microstructures such as mica fish, σ fabric and garnet deformation indicate the dextral shear deformation movements of study area. Based on the obtained results of this research, the stages of tectonic evolution of Darreh Sary area were developed. 相似文献
9.
《中国地球化学学报》2006,(Z1)
Background: With development of intensive agriculture in the agricultural regions of the Northern provinces (Caspian Sea coasts), which involves frequent pesticide use in highly mechanized cash-crop cultures. To investigate and provide information on pest… 相似文献
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Vahid Karkehabadi Hamidreza Zarei Ali Uromeihy Hamidreza Karkehabadi 《Geotechnical and Geological Engineering》2014,32(5):1353-1362
Nowadays, the world is witnessing the ever increasing need of Tunnel excavation due to their unique features and the kind of human applied plans. This has led to increase in demand of excavating this engineering factor. Tunnel excavation process faces a lot of challenges due to environmental and technological complexities which causes the economic evaluation and investigation of this project to be difficult. It is tried to develop the proposed model with regard to efficiency concept in order to evaluate and investigate the efficiency of relative economic performance of Tunnel excavation projects and turn to its modeling and implementing by data envelopment analysis and Fuzzy DEMATEL techniques. The results in Iran showed that the proposed model can turn to investigation and evaluation of economic efficiency of Tunnel excavation by considering two optimistic (ideal) and pessimistic perspectives such that the Tunnel excavation process of “Karaj water transition” and “Cheshmelangan water transition” among 12 rock Tunnel excavation projects of Iran in the time period of 1998–2013 were respectively introduced as the most efficient and the most inefficient rock Tunnel excavation projects. 相似文献
12.
The Neo-Tethyan subduction in Iran is characterized by the Urumieh–Dokhtar magmatic arc (UDMA), formed by northeast-ward subduction of the oceanic crust beneath the central Iran. This belt coincides with the porphyry copper metallogenic belt that comprises several metallogenic zones, including Ahar–Jolfa in northwest Iran. The Ahar–Jolfa metallogenic zone encompasses two main batholiths of Qaradagh and Sheyvardagh and numerous intrusive bodies of Cenozoic, which have produced many base and precious metal deposits and prospects. The former is considered as continuation of the Meghri–Ordubad pluton in South Armenian Block (SAB), which also hosts porphyry copper deposits (PCDs). The Sungun PCD is the largest occurrence in northwest Iran. Rhenium-Osmium ages of Sungun molybdenites are early Miocene and range between 22.9 ± 0.2 and 21.7 ± 0.2 Ma. Comparison of the ages obtained here with published ages for mineralization across the region suggests the following sequence. The earliest porphyry Cu–Mo mineralization event in northwest Iran is represented by Saheb Divan PCD of late Eocene age, which is followed by the second epoch of middle Oligocene, including the Cu–Mo–Au mineralization at Qarachilar and the Haftcheshmeh PCD. Mineralization in Sungun, Masjed Daghi, Kighal and Niaz deposits corresponds to the third mineralization event in northwest Iran. The first epoch in northwest Iran postdates all Eocene mineralizations in SAB, while the second epoch is coeval with Paragachay and the first-stage of Kadjaran PCDs. Its third epoch is younger than all mineralizations in SAB, except the second stage in Kadjaran PCD. Finally, the Cu mineralization epochs in northwest Iran are older than nearly all PCDs and prospects in Central Iran (except the Bondar Hanza PCD), altogether revealing an old to young trend along the UDMA and the porphyry Cu belt towards southeast, resulted from diachronous, later closure of the Neo-Tethyan oceanic basin in central and SE Iran. 相似文献
13.
Geotectonics - The northeastern part of the Tabriz, Khaje area has been studied to determine the relationship between the orientation of local structures and regional tectonics, and the influence... 相似文献
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The objective of this study is to evaluate the seismic hazard at the Esfarayen-Bojnurd railway using the probabilistic seismic hazard assessment (PSHA) method. This method was carried out based on a recent data set to take into account the historic seismicity and updated instrumental seismicity. A homogenous earthquake catalogue was compiled and a proposed seismic sources model was presented. Attenuation equations that recently recommended by experts and developed based upon earthquake data obtained from tectonic environments similar to those in and around the studied area were weighted and used for assessment of seismic hazard in the frame of logic tree approach. Considering a grid of 1.2 × 1.2 km covering the study area, ground acceleration for every node was calculated. Hazard maps at bedrock conditions were produced for peak ground acceleration, in addition to return periods of 74, 475 and 2475 years. 相似文献
15.
Koohbanani Hamidreza Yazdani Mohammadreza Hosseini Sayyed Keivan 《Natural Hazards》2020,103(1):785-798
Natural Hazards - Due to excessive harvesting of underground water resources in many important aquifers inside Iran, ground subsidence is occurring at different speeds. In present study, InSAR... 相似文献
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Tehran lies on the southern flank of the Central Alborz, an active mountain belt characterized by many historical earthquakes, some of which have affected Tehran itself. The border between the Alborz Mountain and the Tehran’s piedmont (northern part of Tehran City) is marked by the North Tehran Fault (NTF), dividing the Eocene rock formation from the alluvial units of different ages (Early Pleistocene to the recent alluvium). A detail mapping of the piedmont, combined with structural study reveal that two active thrust faults (situated south of the NTF) are of importance for hazard assessment of the City. The geomorphological evidences along the NTF are not in agreement with an active fault, indicating that the fault activity may have been shifted southward. Furthermore differentiation of newly recognized alluvial units and their inferred ages, together with the mapped fault pattern permit us to characterize the Quaternary deformation. The Late Pleistocene alluvial deposits consist of three alluvial fans among them the youngest one together with the modern alluvial fan defines the Holocene deposit. The present deformation in the piedmont is accommodated along vertically left-lateral strike-slip faults and low-angle thrust faults trending in range from N070 to N110E. 相似文献
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《International Geology Review》2012,54(8):1039-1050
Basic volcanic rocks from Tafresh, west Kashan, and west Nain volcanic successions in the central part of Urumieh-Dokhtar Magmatic Assemblage (UDMA) of Iran yield K–Ar ages ranging from 26.8 to 18.2 Ma. These ages indicate significant Late Oligocene–Early Miocene basic volcanism in the UDMA. These ages, combined with K–Ar ages of 26.0 and 14.1 Ma, respectively, for associated low-silica and high-silica adakites, help constrain reconstructions of the UDMA geodynamic evolution. Late Oligocene–Early Miocene slab roll-back associated with an asthenospheric mantle influx are suggested as the major processes responsible for concurrent volcanism showing Nb–Ta-depleted, Nb–Ta-enriched and low-silica adakite signatures. Slab roll-back, the likely consequence of a decrease in subduction velocity, led to partial melting of the subducted slab and produced Early–Middle Miocene high-silica (dacitic) adakites. Oligocene to Miocene volcanic rocks do not conform to the Oligocene continental collisional model for the UDMA, rather they suggest a decrease in the subduction rate that prompted the asthenospheric mantle influx. 相似文献
18.
The Sanandaj–Sirjan Zone (SSZ), as the metamorphic-magmatic core of the Zagros Orogen in southwestern Iran, contains several styles of gold deposit of Phanerozoic age. The northern SSZ includes an ENE-trending goldfield belt. This area that encompasses the main orogenic gold deposits, e.g., Qolqoleh, Kervian, Qabaqhlujeh, and the Barika VMS goldfield, was chosen for this research to study the spatial and temporal relationships between gold mineralization and orogenic phases. Regarding the rock unit variations, metamorphism, magmatism and the settings of the structures, the study area is divided into four distinct tectonic blocks, separated by three main NW-trending thrust faults (suture lines) including, from NE to SW, the Tamugheh, the Ebrahim Hesar and the Zagros main thrust (ZMT) faults. The area between the Tamugheh and Ebrahim Hesar faults is a tectonized/uplifted basement of accretionary wedge-originated thrust slivers, hosting the above orogenic gold mineralizations. The other area between the here termed Ebrahim Hesar fault and the ZMT is an island-arc basin, proposed here as the Sardasht–Barika zone, including the only recognized massive sulfide gold district all over the SSZ, named Barika. The Barika goldfield was metamorphosed, deformed and enriched due to the island-arc collision to the Arabian continent, before the closure of Neotethys on the eastern flank. 相似文献
19.
Seyed Ali Mazhari Sadraldin Amini Jalil Ghalamghash Fernando Bea 《Arabian Journal of Geosciences》2011,4(1-2):59-67
The granitic unit is a component of the Naqadeh plutonic complex, NW of Sanandaj–Sirjan Zone (NW Iran). This unit is composed of high-K calc-alkaline, slightly peraluminous (ASI?=?1.12–1.17) evolved monzogranites. These monzogranites have 41.85?±?0.81 Ma (zircon U–Pb sensitive, high-resolution ion microprobe (SHRIMP) age) with two inherited zircon ages of 98.5?±?1.7 and 586.6?±?13.1 Ma, respectively. The only enclave type consists of quartz-amphibolite enclaves indicating residual parental rocks. Chemical and isotopic (87Sr/86Sr40Ma?=?0.708638; εNd40Ma?=??4.26) characteristics of monzogranites suggest that they could be derived by partial melting of crustal mafic rocks followed by some assimilation of metasedimentary rocks. With regards to inherited zircon age and quartz-amphibolite composition of Naqadeh granite, the old mafic rocks of this complex (Naqadeh dioritic rocks with ~100 Ma) can be considered as parental rocks, and their partial melting under high water content, and assimilation of produced melt by metasedimentary rocks, would lead to the generation of a Naqadeh granitic unit. 相似文献
20.
The metasedimentary and granitoid rocks of the Soresat Metamorphic Complex occur along the northern margin of the Sanandaj–Sirjan Zone in northwest Iran. Four different deformational events (D1–D4) are recorded in the Soresat Metamorphic Complex. The D1 and D2 progressive deformation events resulted from north-northeast–south-southwest regional horizontal shortening due to the subduction of Neo-Tethys oceanic lithosphere beneath the Sanandaj–Sirjan Zone. Post-suturing convergence between Arabia and Iran, which resulted in a right lateral-reverse displacement along the suture caused the north-northwest–south-southeast horizontal shortening of D3. D4 is recorded by normal faulting. Andalusite, cordierite and sillimanite (fibrolite) record the thermal peak (with a geothermal gradient >30°C/km). Field and microscopic studies of intruded granitoid rocks in the Soresat Metamorphic Complex divide them into three major groups: (i) syn-deformation (syn-D2) granitic gneiss; (ii) late- to post-deformation (late- to post-D2) granites and granodiorites; and (iii) post-deformation (post-D2) alkali granites. 相似文献