ORIGINAL_ARTICLE
Exploratory palynological analysis of Quaternary lacustrine deposits around Damavand volcano, Northern Iran
Palynological analyses from exposed palaeolacustrine deposits located at the flanks of Damavand volcano, in the central AlborzMountains in Northern Iran, provide a broad idea of the temporal variation of vegetation according to climate changes during a rangeof limited time intervals during the Quaternary period. This research reveals that the regional vegetation of the study area had been asemi-arid mountain steppe since the early Quaternary. However, moderate expansions of open woodlands and aquatic/marshy taxaindicate less arid climatic conditions. Some of these comparatively less arid phases during the last 70 ka are contemporaneous with theclimatic amelioration phases during previous glacial periods in the Himalayan region. Although the results are scattered through time,they clearly show the potential of the study area for further palynological investigations with the aim of understanding the regionalvegetation response on global climate changes in Northern Iran
https://geopersia.ut.ac.ir/article_51188_870d9f9f6bb8e9ab0b793e54a044f1dd.pdf
2014-06-01
1
10
10.22059/jgeope.2014.51188
Iran
Damavand Volcano
Quaternary
pollen
vegetation
Jyoti
Sharma
jyotilko@gmail.com
1
Birbal Sahni Institute of Palaeobotany, 53- University Road, Lucknow, 226007, India
AUTHOR
Habib
Alimohammadian
halimohammadian@gmail.com
2
Environmental and Palaeomagnetism Laboratory, Geological Survey of Iran (GSI), Tehran, Iran
AUTHOR
Amavala
Bhattacharyya
amalava@yahoo.com
3
Birbal Sahni Institute of Palaeobotany, 53- University Road, Lucknow, 226007, India
AUTHOR
Parminder
Ranhotra
pranhotra@yahoo.com
4
Birbal Sahni Institute of Palaeobotany, 53- University Road, Lucknow -226007, India
AUTHOR
Morteza
Djamali
morteza_djamali@yahoo.com
5
IMEP CNRS UMR 6116, Eurôpole Méditerranéen de I′Arbois, Pavillon Villemin BP 80 , 13545 Aix-en-Provence Cedex 04, France
AUTHOR
Steffen
Scharrer
steffen.scharrer@senckenberg.de
6
Senckenberg Research Institute, Research Center ‘The Role of Culture in Early Expansions of Humans’ of Heidelberg Academy of Sciences and Humanities, Senckenberganlage 25, 60325 Frankfurt/Main, Germany
AUTHOR
Angela
Bruch
angela.bruch@senckenberg.de
7
Senckenberg Research Institute, Research Center ‘The Role of Culture in Early Expansions of Humans’ of Heidelberg Academy of Sciences and Humanities, Senckenberganlage 25, 60325 Frankfurt/Main, Germany
LEAD_AUTHOR
ORIGINAL_ARTICLE
Biostratigraphy and paleo-ecological reconstruction on Scleractinian reef corals of Rupelian-Chattian succession (Qom Formation) in northeast of Delijan area
In this research, biostratigraphy and paleo-ecological reconstruction of the Qom Formation deposits in Bijegan village, northeast ofDelijan, are discussed. The studied section is situated in the western margin of the Urumieh-Dokhtar magmatic arc (the intra-arc basin).The Qom Formation deposits at the studied area are Rupelian-Chattian in age. Larger benthic foraminifers are used for biostratigraphywith the occurrence of 14 genera and 16 species, which led to the identification of two faunal assemblages: 1 Nummulites vascus-N.fichteli, and 2. Lepidocyclina-Operculina-Ditrupa. Oligocene coral assemblages from the studied section are investigated with regardto its palaeoecological implications. These corals comprise four species of four genera and are compared with faunas from theMediterranean Tethys and Indo-pacific Ocean, and they have an affinity to corals of the Mediterranean Tethys. Re-deposited branchingPorites coral assemblages probably occurred in patchy dense frameworks which were destroyed during storm events and re-depositedin the present stratified horizons. The Porites-Faviidae assemblage represented a common feature of Oligocene coral faunas andincreasing water energy.
https://geopersia.ut.ac.ir/article_51189_353a1d9bf8d5aab97af7e00ea833efdc.pdf
2014-06-01
11
24
10.22059/jgeope.2014.51189
Qom Formation
Rupelian-Chattian
Biostratigraphy
Paleo-ecology
Mahnaz
Karevan
ma.karevan@gmail.com
1
Department of Geology, Faculty of Science, Ferdowsi University of Mashhad, Iran
LEAD_AUTHOR
Hosein
Vaziri-Moghaddam
ali.ataheri2@gmail.com
2
Department of Geology, University of Isfahan, Iran
AUTHOR
Asadollah
Mahboubi
amahboobi2001@yahoo.com
3
Department of Geology, Faculty of Science, Ferdowsi University of Mashhad, Iran
AUTHOR
Reza
Moussavi-Harami
harami2004@yahoo.com
4
Department of Geology, Faculty of Science, Ferdowsi University of Mashhad, Iran
AUTHOR
ORIGINAL_ARTICLE
Petrophysical and durability tests on sandstones for the evaluation of their quality as building stones using Analytical Hierarchy Process (AHP)
Due to their widespread availability, sandstones are commonly used as a natural stone for buildings, monuments and sculptures. In thecurrent study, nine sandstone samples from the Upper Red Formation (specified by the letters A, B, C, CG, S, S1, Sh, Tr and Min)were studied from a petrophysical point of view and their durability was evaluated. Then, their suitability as building stones wasassessed using an AHP model. Laboratory tests, including polarizing optical microscopy, hydric tests, ultrasound, uniaxial compressivestrength, salt crystallization cycles, freeze–thaw cycles and slake durability index tests, were performed. Accelerated ageing testscaused some changes in the dry weight, P-wave velocity, slake durability index and uniaxial compressive strength, especially duringsalt crystallization cycles. The results from our laboratory investigations show that sandstones from the same stratigraphic layer canshow major differences in their petrophysical and weathering properties. These differences result from their different diagenesis(causing varying pore space, water balance and strength properties) and also from the mineralogical composition. In the next stage ofthis study, an AHP model was developed to classify the qualities of sandstones according to their physical and mechanical properties,and also their resistance against weathering processes. Seven primary-level criteria, including uniaxial compressive strength, strengthreduction factor (R), Initial porosity, weight loss (%) in salt crystallization test, Id15 under salt crystallization test, main grain contacttype and main mineralogical composition, and 23 secondary level criteria were selected as input parameters. Results showed that theAHP model can considerably predict the suitability of building stones. Of the analysed sandstones, samples B and C are very suitablefor construction purposes because of their good strength properties (high compressive and tensile strength, low softening degree) aswell as their low porosity. Furthermore, samples Tr, S and S1 are very unsuitable sandstones for use in construction due to their highnumber of lithoclasts, high porosity and low compressive and tensile strength.
https://geopersia.ut.ac.ir/article_51190_c44fab2c585d1bc424615318b945e28b.pdf
2014-06-01
25
43
10.22059/jgeope.2014.51190
Sandstone
Upper Red Formation
building stone
ageing test
AHP
Mohamad Hossein
Ghobadi
amirghobadi@yahoo.com
1
Deparment of Geology, Bu-Ali Sina University, Hamedan, Iran
LEAD_AUTHOR
Reza
Babazadeh
babazadeh64@gmail.com
2
Deparment of Geology, Bu-Ali Sina University, Hamedan, Iran
AUTHOR
Saeed
Khodabakhsh
kadkhodaie_ali2@tabrizu.ac.ir
3
Deparment of Geology, Bu-Ali Sina University, Hamedan, Iran
AUTHOR
ORIGINAL_ARTICLE
A GIS-based comparative study of the analytic hierarchy process, bivariate statistics and frequency ratio methods for landslide susceptibility mapping in part of the Tehran metropolis, Iran
The high hillsides of the Tehran metropolis are prone to landslides due to the climatic conditions and the geological, geomorphologicalcharacteristics of the region. Therefore, it is vitally important that a landslide susceptibility map of the region be prepared. For thispurpose, thematic layers including landslide inventory, lithology, slope, aspect, curvature, distance to stream, distance to fault,elevation, land use, and precipitation were used. Next, weighted raster thematic maps with assigned values for their classes weremultiplied by the corresponding weights and combined to yield a simple map where each cell has a certain landslide susceptibilityindex (LSI) value. After reclassification, this represents the final susceptibility map of the study area. Finally the three maps werecompared to assess the strength of the corresponding methods. In this study area, 74% of landslides occurred in highly or completelyshaly units. Lithology, slope, distance to fault and distance to stream data layers were found to be important factors in the study area.The outcome of this comparison was the conclusion that the active landslide zones do not completely fit into the high and very highsusceptibility classes. However, 99.6% of these landslide zones fall into the high and very high susceptibility zones of the bivariatestatistics (WI) method, or 74.5% in the case of the analytic hierarchy process (AHP) method and 97.2% with the frequency ratio (FR)method. The results showed the WI and FR methods to give a more realistic picture of the actual distribution of landslide susceptibilitythan the AHP method.
https://geopersia.ut.ac.ir/article_51191_f1726bdf2b5b3e6cbf08c74828ce00d2.pdf
2014-06-01
45
61
10.22059/jgeope.2014.51191
landslide
Susceptibility
Analytic Hierarchy Process
Wi
GIS
FR
Samad
Moradi
samadmoradi39@yahoo.com
1
Department of Geology, Faculty of Basic Science, Shahid Chamran University,Ahvaz, Iran
LEAD_AUTHOR
Mohsen
Rezaei
mohsen-rezaei@shirazu.ac.ir
2
Department of Geology, Faculty of Basic Science, Kharazmi University, Iran
AUTHOR
ORIGINAL_ARTICLE
Crystallographic preferred orientations analysis of quartz crystals in Psammite using electron backscatter diffraction,western Ireland
The present study investigates the crystal preferred orientation (CPO) of quartz crystals in psammitic rocks to ascertain the deformationmechanism using electron backscatter diffraction (EBSD) on quartz crystals from north of the Renvyle-Bofin Slide (RBS) nearLetterfrack in western Ireland. Complete crystallographic orientations were determined for several thousand individual quartz crystalsin psammite samples to provide a dataset for exploring the active deformation mechanism(s). Quartz crystallographic orientations areplotted as pole figures and contour diagrams in <0001> and <11¯20> directions. Quartz-c-axis patterns show maxima in the Y axis ofthe pole figure, which can be explained by the dominance of prism <a> gliding, indicating that dislocation creep was the dominantdeformation mechanism.
https://geopersia.ut.ac.ir/article_51192_7a6fa44479a580f86d656e7f114d7799.pdf
2014-06-01
63
71
10.22059/jgeope.2014.51192
Quartz crystals
Crystal preferred orientations
Deformation mechanism
Electron backscatter diffraction
Aziz
Rahimi-Chakdel
rahimiaz@yahoo.co.uk
1
Department. of Geology, Faculty of Sciences, Golestan University, Gorgan, IRAN
LEAD_AUTHOR
ORIGINAL_ARTICLE
A review of research dealing with isotope hydrology in Iran and the first Iranian meteoric water line
For more than half a century isotopes have been employed as a powerful tool in studying various aspects of water resources in a largenumber of countries. However, in developing countries like Iran the application of such techniques is in its infancy. The first research inIran was carried out in 1975 to identify the source of saline groundwaters in south Iran, and the first national conference on the applicationof stable isotopes was held in 2013. Altogether, there are 70 publications which fall into seven categories, including the isotopiccomposition of precipitation/groundwater (35.75%), sources of salinization and hydrothermal water (18.57%), natural recharge andrecharge areas of springs (17.14%), informative studies and groundwater modelling (11.42%), groundwater–surface water interaction(7.14%), karst development and hydrograph separation (5.71%), and pollution and pollutant transportation (4.28%). Nationwide, there areissues which require the application of isotopes (e.g., the determination of recharge areas of important springs and the identification of thesources of groundwater pollution) but a lack of laboratory facilities does not allow scientists to tackle these problems. In this research, wehave also constructed the first Iranian meteoric water line, the slope and the deuterium excess of which are 6.89 and 6.57‰, respectively.
https://geopersia.ut.ac.ir/article_51193_a0029a98378f7b460209f66fb0b1746c.pdf
2014-06-01
73
86
10.22059/jgeope.2014.51193
Iran
Isotope hydrology
groundwater
IMWL
GMWL
Abdollah
Shamsi
a.shamsi@shahroodut.ac.ir
1
Faculty of Earth Sciences, University of Shahrood, Shahrood, Iran
LEAD_AUTHOR
Gholam
Kazemi
g_a_kazemi@shahroodut.ac.ir
2
Faculty of Earth Sciences, University of Shahrood, Shahrood, Iran
AUTHOR
ORIGINAL_ARTICLE
Chemistry of minerals and mass changes of elements during sodiccalcic alteration of the Panj-Kuh intrusive body (Damghan, Iran)
Exact petrography and mineral chemistry investigations of pristine and altered rocks of the post-Eocene Panj-Kuh pluton show thatsubsequent to emplacement and crystallization, rocks were subjected to two secondary composition equivalents, sodic-calcic andpotassic alterations, respectively. Fresh rocks have syenitic composition and contain plagioclase (labradorite), K-feldspar, magmaticdiopside, biotite and minor magnetite, sphene and apatite. The rocks, subjected to Na-Ca alteration, are characterized by a bleachedappearance and in point of modal classification referred to as monzonite. Albitization of the corner of plagioclase (An10Ab85Or5),pervasive scapolitization of the plagioclases (marialite, Ma97Me2) and albite with chessboard twinning are some common properties ofrocks subjected by this type alteration. Magmatic magnetite is enclosed in pyroxene and biotite and is also dissolved and partiallyremoved. This type of metasomatism is structurally controlled by fracturing, with filling minerals of albite, scapolite, analcime,clinopyroxene, sphene and apatite (scapolite-albite veins). The pyroxene has the same composition in syenites, monzonite and inscapolite-albite veins (on average, Wo48En38Fo12). This means that the secondary hydrothermal effects do not tend to alter thecomposition of primary clinopyroxene. The average Or content of potassium feldspar crystals in altered and unaltered rocks range fromOr90 to Or84. According to the isocon method and the obtained plots, Ti and REEs were relatively immobile during Na-Ca alterationand the mass change calculations varied from 1 to 20%, depending on the intensity of alteration. By contrast, the washed-out contentsof K and Fe invaded the other rocks and created potassic zone alteration. These rocks were characterized by the conversion ofmagmatic pyroxene and biotite to shreddy biotite (with dark green pleochroism and secondary fine sphene), as well as plagioclasesurrounded by rinds of potassium feldspar.
https://geopersia.ut.ac.ir/article_51194_e062d960777231cbb83e01f5b9bc0274.pdf
2014-06-01
87
102
10.22059/jgeope.2014.51194
syenite
sodic-calcic and potassic alterations
mineral chemistry
Mass Transfer
Damghan
Iran
Maryam
Sheibi
inactivesheibi@shahroodut.ac.ir
1
School of Earth Sciences, Shahrood University of Technology, Shahrood, Iran
LEAD_AUTHOR
ORIGINAL_ARTICLE
Geochemical and isotopic (Nd and Sr) constraints on elucidating the origin of intrusions from northwest Saveh, Central Iran
Three intrusive granitoid bodies from northwest Saveh, central Iran, are embedded in volcanic sedimentary rocks of the Eocene,forming isolated small outcrops: Khalkhab quartz monzodioritic units (SiO2: ~52-57 wt %) to the northwest, Neshveh granodioriticunits (SiO2: ~62-71 wt %) to the northeast, and Selijerd granodioritic units (SiO2: ~63-69 wt %) to the southeast. The Khalkhab unit iscomposed of quartz monzogabbro and quartz monzodiorite with medium- to coarse-grained textures. The Neshveh unit is composedmainly of granodiorite with subordinate granite of medium grain size and a porphyritic texture with plagioclase megacryst. The Selijerdunit ranges from granodiorite to tonalite with a medium- to coarse-grained granophyric texture. The rocks studied display a relativelyhigh Na2O content,with a molecular A/CNK ratio less than 1.1, Na2O/ K2O ratio of ~2.06 and calc-alkaline affinity. They containmodal clinopyroxene, hornblende, magnetite and titanite, suggesting I-type characteristics for these rocks and formation in an activecontinental margin. Isotopic data (87Sr/86Sr39Ma= 0.704536-0.704860; ε(Nd)39Ma= 2.2-3.9) from northwest Saveh intrusive rocks areplotted to the left of bulk silicate Earth. These ratios, together with geochemical data, suggest that the parent magmas of the rocksstudied might be generated by crystal fractionation of arc basalts in crustal magma chambers, coupled with some lower crustalassimilation prior to silica enrichment, to form quartz monzogabbros. Consequently, granodiorites formed dominantly by crystalfractionation from evolved parental magmas that ascended into the upper crustal magma chambers.
https://geopersia.ut.ac.ir/article_51195_d3d2dc4890b8489c7cc67b0b7a1d5d67.pdf
2014-06-01
103
123
10.22059/jgeope.2014.51195
Saveh
Fractional Crystallization
I-Type Granitoid
Volcanic Arc
Central Iran
Mehdi
Rezaei-Kahkhaei
rezaei@shahroodut.ac.ir
1
Department of Petrology and Economic Geology, Faculty of Earth Sciences, Shahrood University, Iran
LEAD_AUTHOR
Dariush
Esmaeily
esmaili@khayam.ut.ac.ir
2
Department of Geology, University College of Sciences, University of Tehran, Tehran, Iran
AUTHOR
Carmen
Carmen Galindo Francisco
cgalindo@geo.ucm.es
3
Departamento de Petrología y Geoquímica. Universidad Complutense –IGE (CSIC). C/ José Antonio Novais, n 2, 28040-Madrid, Spain
AUTHOR
ORIGINAL_ARTICLE
Persian Abstracts
https://geopersia.ut.ac.ir/article_51196_f1a3259247e3d1a155adce61a34059dd.pdf
2014-06-01
1
4
10.22059/jgeope.2014.51196