M. Mirjalili; F. Ghaemi; B. Rahimi; M. Moshrefifar; M. Gholamzadeh
Abstract
The study area is located in the east of Yazd and is part of Yazd block (western block of central Iran). There are two major fault systems, Anar and Kharanagh with lengths of 100 and 62 km and numerous minor faults represents an important tectonic phenomenon in the region. The aim of this study is to ...
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The study area is located in the east of Yazd and is part of Yazd block (western block of central Iran). There are two major fault systems, Anar and Kharanagh with lengths of 100 and 62 km and numerous minor faults represents an important tectonic phenomenon in the region. The aim of this study is to investigate neotectonics in this area by using geomorphic indicators. To achieve this goal, have been used of seven geomorphic indicators: Hypsometric integral (HI), Drainage basin asymmetry factor (AF), Stream length- gradient index (SL), Mountain Front sinuosity (Smf) and the ratio of valley floor width to depth Valley (Vf), River sinuosity index (S), Basin shape factor (Bs). Based on Active tectonics indices (Iat), the study area is divided in Four terms of tectonic activity rates, category 1 (very high tectonic activity, 7.4% of the region), category 2 (up 74%), category 3 (average 11%) and category 4 (less 7.4%). Morphotectonical and morphological evidences indicate that the rate of tectonic activity in this region is moderate to high. According these evidences, the northern part of Kharanagh fault and southwestern part of Anar fault are more active than other parts.
Economic Geology
S. Maleki; A. A. Calagari; K. Siahcheshm; S. Alirezaei
Abstract
Khak Sorkh iron deposit located about 42 km northwest of Nadushan town in Yazd Province. Host rock include upper Triassic-Jurassic limestone which are intruded by Oligo-Miocene granitoid bodies. Mineralization is dominated by magnetite, and serpentine is the main waste mineral. Skarn mineral assemblages ...
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Khak Sorkh iron deposit located about 42 km northwest of Nadushan town in Yazd Province. Host rock include upper Triassic-Jurassic limestone which are intruded by Oligo-Miocene granitoid bodies. Mineralization is dominated by magnetite, and serpentine is the main waste mineral. Skarn mineral assemblages include clinopyroxene, garnet, tremolite phlogopite and epidote. The characteristics of mineralization are: magnetite mineralization in two generations, presence of serpentine as the main waste mineral, hornfelsed greywacke units which come between intrusive bodies and skarned limestone units, absence of obvious zoning in endoskarn and exoskarn parts, presence of Ni-Co-As sulfides, high amount of Zn, As, Co and Mn in magnetite geochemical results and the increasing Fe along with decreasing Mg contents in magnetite at both deposit and crystal scales from primary to secondary types. Minor elements contents of geochemical results have been used for distinguishing of different mineral deposits (e.g, Dare et al., 2012; Dupuis and Beaudoin, 2011; Nadoll et al., 2012) and they are in good accordance to hydrothermal and skarn type deposits like: low contents of Cr (less than 10 ppm), high contents of Mg (2.2 to 7.5 ppm), low TiO2 (from 0.01 to 0.3 ppm), low amounts of incompatible elements including Ag (
A Zahedi; M Boomeri
Abstract
The Panah-Kuh skarn is situated in 50km NW of Taft City in Yazd province. Inrtusion of granodioritic stock into the calcareous-dolomitic rocks of Permian Jamal Formation led to formation of calcic and magnesian skarns. The REE patterns of skarns and its forming garnets show Eu/Eu* and Ce/Ce*ratios increase ...
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The Panah-Kuh skarn is situated in 50km NW of Taft City in Yazd province. Inrtusion of granodioritic stock into the calcareous-dolomitic rocks of Permian Jamal Formation led to formation of calcic and magnesian skarns. The REE patterns of skarns and its forming garnets show Eu/Eu* and Ce/Ce*ratios increase with increasing of ∑REE, implying that skarn forming fluids were dominantly of magmatic origin, whereas (Pr/Yb)cn ratio decrease almost with increasing of ∑REE that implying the magmatic fluids granitoid-derived had not much REE during the Panah-Kuh skarn formation. Based on the fluid inclusion data from garnet, fluid temperature and salinity in the prograde stage vary between 308-380oC and 12.6-23.8 wt.% NaCl equivalent, respectively. Inclusion fluids in the calcite had lower temperature (T<280°C) and fluid salinity decline to 3.5 wt.% NaCl equivalent. Mixing and dilution of early magmatic fluids with external fluids (e.g., meteoric waters) caused a decrease in fluid temperature and salinity in latest stage of the skarn formation. Therefore, both REEs and fluid inclusions data suggest the dominant role of magmatic water in the formation of Panah-Kuh skarn.
H Karimian zade; M.R Vaziri; A Lotf abad Arab
Abstract
In order to study the paleoecology of the Aptian gastropods, the Bafgh section with 380 meters thickness, in East of Yazd were studied in detail. In this region, a variety of different fossil groups, including macrofossils (gastropods, ammonites and echinoids) and microfossils (foraminifers and ostracods) ...
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In order to study the paleoecology of the Aptian gastropods, the Bafgh section with 380 meters thickness, in East of Yazd were studied in detail. In this region, a variety of different fossil groups, including macrofossils (gastropods, ammonites and echinoids) and microfossils (foraminifers and ostracods) are present and suggest an Aptian age for this section. 11 genus and species of gastropods are reported for the first time from this section. The microfossils and macrofossils assemblage all show a shallow environment with a suitable conditions for the time of sedimentation in the study area.