Ali Javad porphyry copper-gold deposit is located in Arasbaran porphyry copper belt at northwestern Iran, some 20 km east of Sungun Mine. Porphyry mineralization at the Ali Javad deposit occurred in post-Oligocene qua...Ali Javad porphyry copper-gold deposit is located in Arasbaran porphyry copper belt at northwestern Iran, some 20 km east of Sungun Mine. Porphyry mineralization at the Ali Javad deposit occurred in post-Oligocene quartz monzonite bodies which intruded in the Eocene volcanic rocks. Mineralization occurred as veins, veinlets and dissemination both as hypogene and supergene type. Several types of veinlets were distinguished during the study of the deposit. Fluid inclusion studies on fluids trapped in quartz which were taken from drill core samples indicated a wide range of homogenization temperature in the veinlets from 138°C to 565°C which their salinity demonstrated 33 - 61 wt% NaCl equivalent. Mineralizing fluids density at the deposit was 0.8 - 1.2 g/cm<sup>3</sup>. Fluid inclusion studies suggested that Ali Javad deposit is an Au-rich porphyry copper deposit;its fluid inclusion features were comparable with other porphyry deposits.展开更多
Arasbaran forests are located in East Azerbaijan （northwest Iran）. Increasing of socio-economic problems in this area causes destruction of biodiversity and structure of these forests. Using multipurpose trees such ...Arasbaran forests are located in East Azerbaijan （northwest Iran）. Increasing of socio-economic problems in this area causes destruction of biodiversity and structure of these forests. Using multipurpose trees such as cornelian cherry （Cornus mas L） to encourage villagers to produce forest by-products is a basic approach for preserving these forests. This species grows naturally in Arasbaran forests and the fruit is annually exploited using traditional harvest methods. This study aims to assess the ecological requirements of cornelian cherry and the important factors affecting its distribution. For this purpose, 40 circular sampling plots （300 m2） on various slope aspects were demarcated for sampling the occurrence of cornelian cherry in forest stands. DBH and crown cover percentage on north aspects were significantly greater than on other aspects and 4.5% of all trees were cornelian cherry in mature forest stands. North aspects had more seed-origin trees （standards） of cornelian cherry than coppiced trees, while west facing aspects had more coppiced than standard trees. This species had the highest regeneration rate in the sapling stage of 0–2.5 cm DBH. Thus, I recommend cultivation and development of cornelian cherry as a multi-purpose tree in the Arasbaran region on degraded forest lands on north and west aspects.展开更多
The Haftcheshmeh porphyry Cu-Mo-Au deposit in the Arasbaran metallogenic belt （AMB） of NW Iran contains more than 185 Mt of ore, with a grade ranging from 0.3% to 0.4%. It is hosted within a porphyritic diorite to g...The Haftcheshmeh porphyry Cu-Mo-Au deposit in the Arasbaran metallogenic belt （AMB） of NW Iran contains more than 185 Mt of ore, with a grade ranging from 0.3% to 0.4%. It is hosted within a porphyritic diorite to granodiorite intruded into an older gabbro - diorite intrusion. 40Ar/39Ar analyses of primary magmatic hornblende from the granodiorite porphyry and gabbro - diorite show plateau ages of 26.41 ± 0.59 Ma, with an inverse isochron age of 25.9 ± 1.0 Ma and a plateau age of 27.47 ± 0.17 Ma, with an inverse isochron age of 27.48 ± 0.35 Ma for these two rock types, respectively. Comparing these new age data with those from the nearby Sungun （20.69 ± 0.35 Ma） and Kighal porphyry deposits defines a northwest-southeast Cu-Mo-Au mineralization zone extending for 20 km over the time span of-27 to 20 Ma. Geochemically, Haftcheshmeh rocks are calc-alkaline with high potassium affinities with tectonic setting in relation to volcanic arc setting. Large ion lithophile elements （LILE） such as Th, U and K show enrichment on a primitive mantle normalized diagram （specially Pb）, and are depleted in high field strength elements （HFSE） such as Ti and Nb, pointing to a mantle magma source contamination with crustal materials by subducted oceanic crust.展开更多
This study evaluated the total height of trees based on diameter at breast height by using 23 widely used height-diameter non-linear regression models for mixed-species forest stands consisting of Caucasian oak,field ...This study evaluated the total height of trees based on diameter at breast height by using 23 widely used height-diameter non-linear regression models for mixed-species forest stands consisting of Caucasian oak,field maple,and hornbeam from forests in Northwest Iran.1920 trees were measured in 6 sampling plots(every sampling plot has 1 ha area).The fit of the best height–diameter models for each species were compared based on R2,Root Mean Square Error(RMSE),Akaike information criterion(AIC),standard error,and relative ranking performance criteria.In the final step,verification of results was performed by paired sample t-test to compare the observed height and estimated height.Results showed that among 23 height-diameter models,the best models were obtained from the top five ones including Modified-logistic,Prodan,Sibbesen,Burkhart,and Exponential.Comparison between the actual observed height and estimated height for Caucasian oak showed that Modified–Logistic,Prodan,Sibbesen,Burkhart,and Exponential performed better than the others,respectively(There were no statistically significant differences between observed heights and predicted height(p≥0.05)).Prodan,Modified-Logistic,Burkhart,and Loetch evaluated field maple tree height correctly,and Modified-Logistic,Burkhart,and Loetch had better fitness compared to the others for hornbeam,respectively.Although other models were introduced as appropriate criteria,they could not reliably predict the height of trees.Using the Rank analysis,the Modified-Logistic model for the Caucasian oak and Prodan model for field maple and hornbeam had the best performance.Finally,to complement the results of this study,it is suggested to assess how environmental factors such as elevation,climate parameters,forest protection policy and forest structure will modify height-diameter allometry models and will enhance the prediction accuracy of tree heights prediction in mixed stands.展开更多
A list of Heteroptera collected from Arasbaran Biosphere Reserve(East Azarbayjan Province,northwestern Iran) and neighboring areas is provided. A total of 114 species from 87 genera and 19 families were collected from...A list of Heteroptera collected from Arasbaran Biosphere Reserve(East Azarbayjan Province,northwestern Iran) and neighboring areas is provided. A total of 114 species from 87 genera and 19 families were collected from Arasbaran and vicinity. Two species are new records for Iran: Gerris(Gerris) maculatus Tamanini and Sigara(Vermicorixa) lateralis(Leach).展开更多
文摘Ali Javad porphyry copper-gold deposit is located in Arasbaran porphyry copper belt at northwestern Iran, some 20 km east of Sungun Mine. Porphyry mineralization at the Ali Javad deposit occurred in post-Oligocene quartz monzonite bodies which intruded in the Eocene volcanic rocks. Mineralization occurred as veins, veinlets and dissemination both as hypogene and supergene type. Several types of veinlets were distinguished during the study of the deposit. Fluid inclusion studies on fluids trapped in quartz which were taken from drill core samples indicated a wide range of homogenization temperature in the veinlets from 138°C to 565°C which their salinity demonstrated 33 - 61 wt% NaCl equivalent. Mineralizing fluids density at the deposit was 0.8 - 1.2 g/cm<sup>3</sup>. Fluid inclusion studies suggested that Ali Javad deposit is an Au-rich porphyry copper deposit;its fluid inclusion features were comparable with other porphyry deposits.
文摘Arasbaran forests are located in East Azerbaijan （northwest Iran）. Increasing of socio-economic problems in this area causes destruction of biodiversity and structure of these forests. Using multipurpose trees such as cornelian cherry （Cornus mas L） to encourage villagers to produce forest by-products is a basic approach for preserving these forests. This species grows naturally in Arasbaran forests and the fruit is annually exploited using traditional harvest methods. This study aims to assess the ecological requirements of cornelian cherry and the important factors affecting its distribution. For this purpose, 40 circular sampling plots （300 m2） on various slope aspects were demarcated for sampling the occurrence of cornelian cherry in forest stands. DBH and crown cover percentage on north aspects were significantly greater than on other aspects and 4.5% of all trees were cornelian cherry in mature forest stands. North aspects had more seed-origin trees （standards） of cornelian cherry than coppiced trees, while west facing aspects had more coppiced than standard trees. This species had the highest regeneration rate in the sapling stage of 0–2.5 cm DBH. Thus, I recommend cultivation and development of cornelian cherry as a multi-purpose tree in the Arasbaran region on degraded forest lands on north and west aspects.
基金supported financially by Special Fund of the first author from the Payame Noor University
文摘The Haftcheshmeh porphyry Cu-Mo-Au deposit in the Arasbaran metallogenic belt （AMB） of NW Iran contains more than 185 Mt of ore, with a grade ranging from 0.3% to 0.4%. It is hosted within a porphyritic diorite to granodiorite intruded into an older gabbro - diorite intrusion. 40Ar/39Ar analyses of primary magmatic hornblende from the granodiorite porphyry and gabbro - diorite show plateau ages of 26.41 ± 0.59 Ma, with an inverse isochron age of 25.9 ± 1.0 Ma and a plateau age of 27.47 ± 0.17 Ma, with an inverse isochron age of 27.48 ± 0.35 Ma for these two rock types, respectively. Comparing these new age data with those from the nearby Sungun （20.69 ± 0.35 Ma） and Kighal porphyry deposits defines a northwest-southeast Cu-Mo-Au mineralization zone extending for 20 km over the time span of-27 to 20 Ma. Geochemically, Haftcheshmeh rocks are calc-alkaline with high potassium affinities with tectonic setting in relation to volcanic arc setting. Large ion lithophile elements （LILE） such as Th, U and K show enrichment on a primitive mantle normalized diagram （specially Pb）, and are depleted in high field strength elements （HFSE） such as Ti and Nb, pointing to a mantle magma source contamination with crustal materials by subducted oceanic crust.
文摘This study evaluated the total height of trees based on diameter at breast height by using 23 widely used height-diameter non-linear regression models for mixed-species forest stands consisting of Caucasian oak,field maple,and hornbeam from forests in Northwest Iran.1920 trees were measured in 6 sampling plots(every sampling plot has 1 ha area).The fit of the best height–diameter models for each species were compared based on R2,Root Mean Square Error(RMSE),Akaike information criterion(AIC),standard error,and relative ranking performance criteria.In the final step,verification of results was performed by paired sample t-test to compare the observed height and estimated height.Results showed that among 23 height-diameter models,the best models were obtained from the top five ones including Modified-logistic,Prodan,Sibbesen,Burkhart,and Exponential.Comparison between the actual observed height and estimated height for Caucasian oak showed that Modified–Logistic,Prodan,Sibbesen,Burkhart,and Exponential performed better than the others,respectively(There were no statistically significant differences between observed heights and predicted height(p≥0.05)).Prodan,Modified-Logistic,Burkhart,and Loetch evaluated field maple tree height correctly,and Modified-Logistic,Burkhart,and Loetch had better fitness compared to the others for hornbeam,respectively.Although other models were introduced as appropriate criteria,they could not reliably predict the height of trees.Using the Rank analysis,the Modified-Logistic model for the Caucasian oak and Prodan model for field maple and hornbeam had the best performance.Finally,to complement the results of this study,it is suggested to assess how environmental factors such as elevation,climate parameters,forest protection policy and forest structure will modify height-diameter allometry models and will enhance the prediction accuracy of tree heights prediction in mixed stands.
基金supported by grants from Shahre Rey Islamic Azad University,the National Natural Science Foundation of China(30825006,30970394)the Doctoral Program of Higher Education of China(200800190015)
文摘A list of Heteroptera collected from Arasbaran Biosphere Reserve(East Azarbayjan Province,northwestern Iran) and neighboring areas is provided. A total of 114 species from 87 genera and 19 families were collected from Arasbaran and vicinity. Two species are new records for Iran: Gerris(Gerris) maculatus Tamanini and Sigara(Vermicorixa) lateralis(Leach).
