Tectonics
Zeinab Etemadkhah; Mohammd Mahdi Khatib; Mohammadhossein Zarrinkoub
Abstract
The late Paleocene – early Eocene granitoid intrusions in the northern Sistan suture zone are regarded as potential tools to record tectonic events. A structural study of the Zahri granitoid body, based on the anisotropy of magnetic susceptibility (AMS) technique provides new data to characterize ...
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The late Paleocene – early Eocene granitoid intrusions in the northern Sistan suture zone are regarded as potential tools to record tectonic events. A structural study of the Zahri granitoid body, based on the anisotropy of magnetic susceptibility (AMS) technique provides new data to characterize the internal structure and the kinematic reconstruction. The NW–SE trending body consists basically granite to leucogranite. Based on the results of the analysis of over 360 samples collected from 36 sites, the granitoid body is characterized by a low susceptibility and petrographic observations indicate that paramagnetic minerals such as biotite and amphibole are the most important iron-bearing mineral and can be considered as the main carrier of magnetic susceptibility. Magnetic foliations dominated by moderate dip and foliation strike mostly parallel to the elongated shape of the body, the magnetic lineation mainly trends NE-SW to N-S with plunges to the SW (mean orientation N 197°/32°) and formed during the emplacement and crystallisation of the magma. The Zahri body emplaced in an extensional setting controlled by a NNE-SSW opening direction associated with spaces of the sinistral shear zone in the terminations of Nehbandan fault system during the early Eocene.
Tectonics
ahmad lashgari; magmodreza Hayhat; mohammd mahdi khatib; Mahdi Najafi; Jaume Verges
Abstract
Determining the geometry and folding mechanism in Dezful embayment in the southwest of Iran due to the inclusion of a large amount of Iran's hydrocarbon reserves, also its role in the process of structural evolution of Zagros fold- belt, is important. In present study, structural evolution of Jarik anticline ...
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Determining the geometry and folding mechanism in Dezful embayment in the southwest of Iran due to the inclusion of a large amount of Iran's hydrocarbon reserves, also its role in the process of structural evolution of Zagros fold- belt, is important. In present study, structural evolution of Jarik anticline in the northwest of Dezful embayment have been studied based on 3D seismic data, drilling data that has been provided National Iranian Oil Company remote sensing, and the field observations. According to the provided structural cross sections, geometric variations of Jarik anticline across and along the anticline axis, has been investigated. Gachsaran formation as an upper detachment horizon, causes geometric and structural changes along the anticline axis. It seems that, in the nose of anticline, occurred the detachment folding mechanism associated with concentric geometry. And in the middle section of the anticline,that folding process is more advanced, faulted detachment folding mechanism has acted.
Tectonics
mehdi yousefi; Sayyed Morteza Moussavi; Mohammad Mehdi Khatib; Mohammad yazdani
Abstract
Image logs of 14 wells in Rag sefid anticline are showing 6 main fracture sets treanding N45, EW, N35, N100, N150 and N162 respectively. Development of fractures in the eastern part of the Rag sefid anticline, especially in the frontal edge, are in effect of the propagation fault related folding so that ...
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Image logs of 14 wells in Rag sefid anticline are showing 6 main fracture sets treanding N45, EW, N35, N100, N150 and N162 respectively. Development of fractures in the eastern part of the Rag sefid anticline, especially in the frontal edge, are in effect of the propagation fault related folding so that the most open longitudinal and cross axial fractures show N100 and N10 trends. Due to fold axis rotation 30 degrees to the north In the western part of the anticline the orientation of the fractures have changed and major fractures are longitudinal type and have N160 trend. In the middle and curved part of anticline NE-SW trend fracture sets are more developed by reactivation of hendijan basement fault. Convergence of stress axises as a result of the fault triple interaction In effect of Rag sefid thrust dipping to the north east and dextral shears dut to reactivation of hendijan and southern part of Izef basement faults caused the Restraining bend and dextral shear zone In the western part of the Rag sefid anticline. Creation of this shear zone caused clockwise rotation of anticline axis, rising more in northen west culmination on asmari top formation than southern east culmination, change in fractures orientation and also development and increase the density of fractures in the curved part of Rag sefid anticline.
Tectonics
zahra kamali; magmodreza Hayhat; hamid nazari; mohammd mahdi khatib
Abstract
The Dorud fault, as one of the most important seismicin segments of Zagros main recent fault, near the Arjng area it have northwest-southeast trend and continuity extended in Boroujerd area. This area is determined Kinematic dissimilarity fault the fractal analysis of the fractures, the center of earthquakes ...
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The Dorud fault, as one of the most important seismicin segments of Zagros main recent fault, near the Arjng area it have northwest-southeast trend and continuity extended in Boroujerd area. This area is determined Kinematic dissimilarity fault the fractal analysis of the fractures, the center of earthquakes and drainage using the of box method, For this purpose, the study area was divided into two parts based on the difference in distribution of fractures and epicenter earthquakes. Fractal dimensions of fractures, drainage and epicenter earthquakes are calculated and then compared with each other. Kernel density method to investigate the epicenter earthquakes distribution and drainage in the long fault to rate the dissimilar activity that .In the end, the analysis of evidence Morphotectonic that long it’s to determine the horizontal, vertical displacements and net slip to be paid. Fractal analysis on Kernel density method and evidence Morphotectonic. In the end, the analysis of that long it’s to determine the horizontal, vertical displacements and net slip to be paid. So that results of fractal to indicate that the northern segment of the most dynamic segment spread to be identified. Also The results of the kernel analysis and evidence Morphotectonic indicates that neither the fault that along with passing of units of different ages show different behavior and the amount of angle Rick obtained along the fault is different according to the results achieved in three segment to different long can be divided, so that angle Rick segments 1 and2 respectively126°/16° and124°/22° and long segments respectively 18 and48 kilometer, to notice the high values of rick (more of10°) the two segments have a dominant effect of the component dip- slip relative to strike-slip but the angle rick 131°/4° in segment 3indicate of the action component strike slip that the units alluvial are plain Silakhor this segment long is 44 kilometer.
A. Rashidi; M. M. Khatib; S. M. Mosavi; Y. Jamor
Abstract
In the S,W Lut Block, geodetic moment rate is more than seismic and geological moment rates. Depending on the type of deformation and geometry of the faults, the study area divided to the 4 parts : northern, central, southern and southeastern (South Lut Block) parts. Values of three types of moment ...
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In the S,W Lut Block, geodetic moment rate is more than seismic and geological moment rates. Depending on the type of deformation and geometry of the faults, the study area divided to the 4 parts : northern, central, southern and southeastern (South Lut Block) parts. Values of three types of moment rates in these area are comparing with each other. The most of geodetic moment rate was obtained respectively in northern, central, southern, southeastern parts of the study area. Geodetic moment rate in the northern part is 2.28E+18 Nm.yr, the central part is 1.86E+18 Nm.yr, the southern part is 1.20E+18 Nm.yr and in the southeastern is 1.10E+18 Nm.yr. The most of seismic moment rate was obtained respectively in central, southeastern, southern, northern parts of the study area. Seismic moment rate in the central part is 5.62316E+17 Nm.yr, in the southeast part is 2.05331E+17 Nm.yr, in the southern part is 1.18984E+17 Nm.yr and in the northern part is 1.03408E+17 Nm.yr. According to Seismic map, maximum seismic moment, respectively is along Gowk, Shahdad, Davaran, East Kerman, Mahan, Bam, Kuhbanan, Dahueiyeh, North Faryab Faults. These faults are responsible for large earthquakes in the study area. The most of geological moment rate was obtained respectively in southern, northern, central, southeastern parts of the study area. Values of geological moment rate for the southern part is 4.16246E+15 Nm.yr, northern part is 2.74157E+15 Nm.yr, centra part is 2.5895E+15 Nm.yr and in the southeastern is 1.08894E+15 Nm.yr. In the study area, maximum geological moment rate is respectively related to west Sabzevaran, Jiroft, Raver, Dalfard, Kuhbanan, Naybandan, Bam, Gowk, Davaran faults. According to values of geological and geodetic moment rates in the four parts of study area and based on the value of the release seismic energy in the central and southeastern parts, it seems that in the next time, the most of seismic potential and seismic hazard are respectively in the northern, southern, central, southeastern parts of the study area. In study area, maximum seismic moment are at years 1981, 1998, 2003, 2010, 2011, 1999, 2005 respectively. Ratio of the geodetic moment rate to the seismic moment rate obtained more than 7.9. This ratio reflects the important role of interseismic deformation in this area. According to the ratio seismic moment rate to geodetic moment rate, in four parts of the study area, can be conclude that the northern and southern parts with ratio: 0.04 and 0.09 are slow strain areas and the central and southeastern parts with ratio 0.30 , 0.18 are fast strain areas. Ratio of seismic moment rate to geological moment rate is 0.93%. This value indicates that 0.93% potential of the faults for seismic energy has been released and not been released a big part of the elastic energy in the area.
H Yazdanpanah; M.M Khatib; H Nazari; E Gholami
Abstract
A model suggests the current shear, which originated about 5 Ma ago, has been accommodated by strike-slip faulting within and along the margins of the Lut area. The measured Quaternary slip rate along the Nehbandan fault system to the east and the Nayband fault system to the west margins of the Lut area ...
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A model suggests the current shear, which originated about 5 Ma ago, has been accommodated by strike-slip faulting within and along the margins of the Lut area. The measured Quaternary slip rate along the Nehbandan fault system to the east and the Nayband fault system to the west margins of the Lut area is ~ 5 and ~ 1.7±0.3 mm/year, respectively. Therefore, the observed slip rate is shown to increase from west to the east margin. This has resulted in the development of a dextral strike-slip shear system with heterogeneous slip rate across the Lut area. We have used satellite images, field observations, aeromagnetic data and analogue modeling to measure Cenozoic strain distribution and slip-rate changes in the Lut area. Results show direct linkage between deformation distribution and slip rate changes along the margins of the Lut area.
N Naimi-ghassabian; M. M Khatib; T Ghasemi rozveh; H Nazari; M.R Heyhat
Abstract
The Boushad shear zone (BSZ) is situated in the south of Birjand with at least 45 km length, about 9.2 Km width and strike N90E. The parts of the ophiolite mélange shear zone south of Birjand have changed by this shear zone. The earliest deformation, a polyphasesynmetamorphic deformation which ...
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The Boushad shear zone (BSZ) is situated in the south of Birjand with at least 45 km length, about 9.2 Km width and strike N90E. The parts of the ophiolite mélange shear zone south of Birjand have changed by this shear zone. The earliest deformation, a polyphasesynmetamorphic deformation which occurred entirely in ductile conditions, D1 and D2 deformation phases are related to this deformation. The D3 deformation affected the area after a period of sedimentation and erosion, Tension gash veins are formed simultaneously. The Strike-slip faults, thrust faults and fault related folds were classified as structures related to the D4 tectonic event, the most recent phase of conflict in the region N055 ±10E is formed. Degree of convergence of the shear zone is R = 0.3, that indicating the formation of a dextral Transpression (Slightly oblique-convergent).
P Sadeghi-Farshbaf; M.M Khatib; H Nazari
Abstract
The aim of this research is to investigate triggering of fault slip due to stress perturbation caused by hydraulic fracturing. The importance of this issue is to study the observed destructive effects of dam construction at locations adjacent to the superficial faults. Therefore, we use the Matlab programming ...
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The aim of this research is to investigate triggering of fault slip due to stress perturbation caused by hydraulic fracturing. The importance of this issue is to study the observed destructive effects of dam construction at locations adjacent to the superficial faults. Therefore, we use the Matlab programming and SimDesigner system as an analytical extension. Concentrated stresses are applied after defining the nodes for fracture surfaces. By having the fault surface, analyses start to reach an equilibrium state. By defining the reaction forces in boundary condition, comparison of nodal dislocations become possible. The basis for vertical stress calculation is the upper rock layer and for horizontal stress is Coulomb failure stress. We estimate the stress perturbation through theory of tip stress about tensile fractures. The resultant stress field obtained from combination of fractural and regional stresses gives primary condition to study triggered fault slip and related earthquake magnitude. The results show a maximum 2 meters of cumulative slip along the fault surface close to the hydraulic fracturing. Based on moment magnitude of earthquake calculations, this slip gives a magnitude of 3.8 upon the Richter scale. This process needs the increased precision for nodal dislocations and optimized finite elements in order to better improve the future works.
Y Jalili; M.M Khatib; A Yassaghi
Abstract
Fracture intensity-controlling factors, which include folding mechanism, lithology and thickness of layers, have been investigated in the Asmari Formation of the Kuh-e- Asmari using field studies and satellite images. Parameters such as structural position, spacing and vertical extension of the fractures ...
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Fracture intensity-controlling factors, which include folding mechanism, lithology and thickness of layers, have been investigated in the Asmari Formation of the Kuh-e- Asmari using field studies and satellite images. Parameters such as structural position, spacing and vertical extension of the fractures in the limestone and argillaceous limestone units of different thicknesses in the Asmari Formation sequence in Kuh-e Asmari anticline were studied. The existence of large amounts of low-strength and high-porous clay minerals in the argillaceous limestone has resulted in the overall low strength of the rock, which eventually led to lower intensity of fractures in argillaceous limestone than of that in limestone. Variations in the fracture intensitiesin these two rock types showed that the thickness of the units does not much affect the fracture intensity. Hinge-parallel and hinge-perpendicular fractures resulted from flexural-slip folding and outer-arc extension in the hinge area of the fold exhibit the largest development, and exert the highest effect on wellbore instabilities. Results show that the maximum fracture intensity is in the hinge area of the fold, and that folding mechanism is the most important factor in controlling the intensity of the fractures.
M.A Alimi; M.M Khatib; KH Hessami Azar; M.R Hayhat
Abstract
An array of en-echelon strike-slip faults in eastern Iran results in the formation of releasing and restraining bends or stepovers, within which some faults are hidden in the extensional and contractional parts of the structures. This is investigated in the East Neh-Esmaeilabad left-stepping restraining ...
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An array of en-echelon strike-slip faults in eastern Iran results in the formation of releasing and restraining bends or stepovers, within which some faults are hidden in the extensional and contractional parts of the structures. This is investigated in the East Neh-Esmaeilabad left-stepping restraining stepover. Transpressional deformation in the transverse structure associated with the stepover is expressed as folding and uplifting in the Late Neogene, Quaternary and recent deposits, revealing the Shusf fault as a hidden and blind thrust. Processing of magnetic anomaly maps shows the existence of the Shusf magnetic lineament, which consistently well correlates with the Shusf fault and its hidden segments. Also the hidden part of the fault was investigated by the differential GPS profiles constructed perpendicular to the trend of the Shusf fault scarp. In this study, we used surface morphology surveys, fan median method and satellite images to calculate the cumulative horizontal and vertical offsets related to the Late Quaternary active tectonics along the Shusf fault, measuring mean values of 92 and 4.25 m, respectively. Analysis of the velocity vector recorded in the Nehbandan geodynamic station across the Shusf fault indicates the present-day evolution of the stepover expressed as uplift and left-lateral displacement.
KH Kavyani Sadr; M.M Khatib; M.H Zarrinkoub
Abstract
Cheshmeh Khouri is an area which mainly comprises a zone of parallel, en-echelon faults along which metallic and non-metallic mineralization is observed. Structural controllers are important factors in the formation of the structural elements of the area such as dykes, faults, joints, folds, and particularly ...
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Cheshmeh Khouri is an area which mainly comprises a zone of parallel, en-echelon faults along which metallic and non-metallic mineralization is observed. Structural controllers are important factors in the formation of the structural elements of the area such as dykes, faults, joints, folds, and particularly mineral veins. Three types of dykes are observed: E-W trending wedge-shaped dikes, NW-SE trending folded dikes, and ring dikes, which are all kinematically controlled by structural movements of the area. A regional sinistral shear-compression (transpression) regime across the fault sets of the area has given rise to a large-scale counterclockwise rotation of andesitic blocks, developing a bookshelf structure over the area. Rotation of these blocks has provided open spaces for injection of ore-bearing hydrothermal solutions, which caused widespread alterations. Block rotation has also caused formation of dextral shear zones along the faults, which eventually controlled mineralization through the joint and minor fracture networks associated with these shear zones. Formation of mineral veins affected by the dextral shear zones of the bookshelf structure in the area, and defining the structural complexities and sequential elements as well as mineralization phase led to present a laboratory model which showed a good consistency with the results derived from others studies.
F Porghiasian; E Gholami; M.M Khatib
Abstract
In this study, value of shear strain for the Koch fault zone was determined based on the angle of foliations with the edge of the Koch fault zone. The Koch fault zone with N-S trend is located in northeast of Birjand, at the end northwest of the Sistan structural zone. In the Koch fault zone shear strain(γ) ...
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In this study, value of shear strain for the Koch fault zone was determined based on the angle of foliations with the edge of the Koch fault zone. The Koch fault zone with N-S trend is located in northeast of Birjand, at the end northwest of the Sistan structural zone. In the Koch fault zone shear strain(γ) was calculated based on the foliations, which are from the types of fracture cleavage. Shear strain in central part of the Koch fault zone reaches to 4 degrees, its maximum. The value of shear strain reaches to 2 degrees in southern and northern parts of the Koch fault. The value of shear strain decreases from central part of the Koch fault towards the northern and southern parts. The latter indicates the growth of the fault from the central to the northern and southern parts.
Y Jalili; M.M Khatib; E Gholami; M.R Ghassemi
Abstract
The Chelounak area in northwest of Birjand located in the Sistan suture zone extremity with middle-upper Eocene sedimentary and pyroclastic rocks, folded with different axes and exposed between the Chahak-mosavieh and Mohammadieh-Hessarsangi faults. These folds have a dominant characteristic of the dispersion ...
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The Chelounak area in northwest of Birjand located in the Sistan suture zone extremity with middle-upper Eocene sedimentary and pyroclastic rocks, folded with different axes and exposed between the Chahak-mosavieh and Mohammadieh-Hessarsangi faults. These folds have a dominant characteristic of the dispersion axis trends of NE-SW, NW-SE, and N-S. Geometric-Kinematic Analysis of these folds was carried out by data that taken from the structural interpretations, satellite images, geological maps, structural cross sections and mathematical functions. Aspect ratio, percent shortenings and the rotation folds axes are respectively for folds with NE-SW axis, 0.356-1.6, 20-77% and 28-40°; for folds with NW-SE axes0.352-0.620, 25-41% and 25-40°; and for folds with N-S axes 0.352, 25% and 24°. In this analysis the Chahak and Chelounak synclines and the Chahak anticline with NE-SW axis have maximum shortening and the Shavangan syncline with NW-SE axis has minimum shortening. This Study demonstrated the aspect ratio rises with increasing of shortening. Analysis of the structural elements demonstrates axis change of the Chelounak, Chahak and Hoj noj synclines and the Chahak and Chelounak anticlines with NE-SW Dominant axes affected by the Chahak-Mosavieh fault (~N-S trend) as well as the axis change of the Taj kouh, Shavangan and Hessar sangi synclines with NW-SE dominant axes affected by the Mohammadieh-Hessar sangi fault (~N-S trend). Dispersion of folds axial respect to compressive component has caused difference in aspect ratio, shortening and rotation of fold axes values.
A Rashidi; M.M Khatib; M.R Heyhat; S.M Moussavi
Abstract
In KamarhajiMountain, NW Birjand there are geological structures such as: duplex, pop-Up, triangle zone, flower structures, folding, etc. The duplexes in KamarhajiMountain have E-W trend. They are parallel to the Shekarab fault system. The Shekarab fault is a reverse fault with sinistral component located ...
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In KamarhajiMountain, NW Birjand there are geological structures such as: duplex, pop-Up, triangle zone, flower structures, folding, etc. The duplexes in KamarhajiMountain have E-W trend. They are parallel to the Shekarab fault system. The Shekarab fault is a reverse fault with sinistral component located in the southern of the area; it is considered as one of the terminal branches of the Nehbandan fault. Based on the Geometric-Kinematic analysis, duplexes are of the horsetail structure type, which are set from the side view on each other. There are flower structures in the direction perpendicular to the horsetail structures, caused that the central layers of the duplex structures have the maximum height. Usually in the orogenic regions, the antithetic thrusts with motion opposite to the main thrust are observed. These thrusts are called back thrusts. The hanging wall blocks of two faults, thrust and its back thrust is called pop-Up structure. In addition, in some regions back thrust and new thrust created triangle zone. In duplexes of this Region, ramps have strike slip mechanism with Thrust component. The existing flats are non-horizontal and most of them have thrust mechanism with strike slip component. Due to the mechanism of flat, transfer direction is westward, and since the younger ramps are formed on the hanging wall of previous ramp (In other words, younger orientation is toward the hinterland) the formation of duplexes follows the break-back model. Since the physical model shows a better understanding of the formation model and the relationship between the structures, we have used of the experimental model. The results of experiments show a strong relationship between the geometry of the flat and the geometry of the structures of the area. Based on the paleostress studies and different trends of shortening of structures such as folding, duplexes, two deformational stages were identified. In the first stage, position of strain λ3 axis according to analysis of the conjugate joints, tension joints, and axial surface of folding is N42, 00, N40, 07, and is N38, 14 respectively. The amount of shortening in this stage of deformation is 41.46 %. Position of strain λ3 axis in the second stage of deformation according to analysis of the conjugate joints, tension joints, and E-W trend of thrusts is N83, 02, N84, 00, and N90E respectively. In this stage, strike– slip faults have been further developed. The shortening in this stage of deformation is 20.30 % and the amount of slip along the flats is 2640 meters. According to the geometric-kinematic analysis duplexes formed in the second stage of deformation, which was progressive.
E. Gholami; M. A. A. Nogole sadat; M. M. Khatib; A. Yassaghi
Abstract
Right lateral shear between Central Iran and Afghanestan caused activity of N-S and NW-SE fault zones in eastern Iran. Faults interaction effect on creation of restraining zones and out-crop of ophiolitic rocks along fault zones. Study of geometric and kinematic of structures approache to recognition ...
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Right lateral shear between Central Iran and Afghanestan caused activity of N-S and NW-SE fault zones in eastern Iran. Faults interaction effect on creation of restraining zones and out-crop of ophiolitic rocks along fault zones. Study of geometric and kinematic of structures approache to recognition of structural evolution in fault zones of North-North East Lut plain (north part of Sistan structural zone).
The activation of different structural trends in eastern Iran , Sistan zone , causes a deformation style which is significant different from nearby structural zones. This is referred to the interaction of faults with dominant strike slip mechanism and different N-S and NW-SE trends. This interaction with the greater effect of N-S trends causes development of restraining zones and curved fold axial trends in area between the en-echelon areas of the N-S tending faults.
From point of view of structural geology the study area could be divided in two main parts:
A) Activity of N-S strike slip right-lateral fault zones construct wall damage zones and tip damage zones. En-echelon N-S faults construct link damage zones with ophiolitic out-crops in the overlap area (such as Kasrab and Torshab).
B) Fault zones with NW-SE trend, have right-lateral shear with compressional component mechanism (such as SE Birjand and SE Qaen) that has resulted to a broad and continuous out-crops of ophiolitic rocks. Shortening of folded sedimentary rocks (Tertiary) increased in eastern Sahlabad (Hosseinabad, Pureng, Chakhoo, Shourak, Marghzar, Zahab)from north to south. As an accepted theory displacement increase toward the center part of faults, that could be seen Shooshk- Cheshmehzangi fault zone. This suggests that shortening is related to the fault movement. Unconformity between Tertiary and Cretaceous rocks, out-crop of ophiolitic rocks in the compression area, existence of NE-SW compressional axes along two major trends and growing of fault damage zones in the crossing of two major trends in the NNE Lut plain, demonstrate that major mentioned trends had contemporaneous activity. In the restraining zones , thrust faults causes surface emplacement of older ophiolitic rocks. The more exposure of these older rocks and presence of thrust faults in northern portion of the study area where NW-SE trending faults are abundant, imply the greater effect of the N-S trending faults. Since the major shortening axes in the Sistan zone are considered to be constant , increase in deformation through shortening measurements of the folds also constrain the greater effect of the N-S trending faults.
S. S. Mohammadi; M. Vossoughi Abedini; M. Pourmoafi; M. H. Emami; M. M. Khatib
Abstract
Bibi Maryam Granitoid body with 5 km2 exposure area is located in the east Iranian ophiolite mélange belt in Sistan suture zone. This intrusive body consists of tonalite- quartzdiorite and granodiorite. The main mafic minerals are hornblende and biotite in quartzdiorite-tonalite. Existence of ...
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Bibi Maryam Granitoid body with 5 km2 exposure area is located in the east Iranian ophiolite mélange belt in Sistan suture zone. This intrusive body consists of tonalite- quartzdiorite and granodiorite. The main mafic minerals are hornblende and biotite in quartzdiorite-tonalite. Existence of microdioritic enclave in tonalite and its absence in granodiorites is one of the main characteristics of the body. Perthitic and granophyric textures in granodiorites represent low water vapor pressure and relatively fast crystallization, respectively. Geochemical study of rock samples shows that the body is calc-alkaline and metaluminous to peraluminous. Trace element patterns in spider diagrams represent a trough for Nb and enrichment for K, Rb, Ba and Th that indicate contamination by crustal materials. Although Bibi Maryam intrusive body cuts the ultramafic rocks, it lacks petrographic and geochemical characteristics of oceanic plagiogranites. The geochemistry of the body is comparable with I-type granitoids and based on tectonic setting it can be classified as orogenic and VAG type.
