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Showing 27 results for Subject: Geology

M P, , R Alipur,
Volume 9, Issue 2 (10-2010)
Abstract

Rudbar Lorestan dam is constructed on Abrudbar River, 100 km south of Aligudarz city. There is a segment of Main Recent Fault(MRF) called Saravand – Baznavid Fault(SBF) at 1.6 km south of dam site. Using Automatic Extraction Method, based on STA Algorithm, lineaments were extracted from sattelite images and Shaded Relif Model. For detailed structural analysis, the study area was divided into three zones based on geological map. In Eslamabad Fault zone, Eslamabad fault is the main structural element, That is of P-type fractures likely. The main structure in the SBF zone is Saravand – Baznavid active Fault, which caused the drainage to be displaced as much as 500–1000m in the northern height of study area. In the Dam axis zone, the main important structure is F1 fault. This fault is about 150 meters in length with right lateral strike slip component. Thermoluminescence dating, sence of movement, dominant slikenside and the orientation of groove marks on the fault plane indicate this fault to be active. Large dicplacements along strike- slip faults in the study area, such as F1 fault, have been considered using shear zone and enechelon models. However the main faults in the study area is SBF, that relate in an enechelon pattern to seismic Dourud fault and has the right potential to movement in the future.
,
Volume 9, Issue 2 (10-2010)
Abstract

Intrusions between Arak and Borujerd in northern Sanandaj Sirjan zone are present different field and lithology. Three different groups: (a) the Astaneh intrusion, (b) the Borujerd complex, and (c), Tavandasht-Gosheh intrusions can be identified. First attempt to date these intrusions began with K-Ar method and obtained ages were about 60Ma based on studies on Alvand in Hamadan. Further Rb-Sr dating, published older ages and revealed two phases 60Ma and -120Ma for Borujerd complex and 100Ma for Astaneh intrusion. Following dating based on zircon, established the age of 170Ma for all unites. In order to cover gaps in data, we have undertaken MS U-Pb zircon geochronological studies for selected granitoids. Results confirm the presence of granitoids with 170Ma in Astaneh and Borujerd complex. But, for first time, the young age of 34.8Ma initiated for Tavandasht intrusions. It could be concluded that emplacements of plutons in this part of Sanandaj Sirjan began in Mid Jurassic (Bathonian stage) and last phase was on Late Eocene (Priabonian stage). However, based on the presence of field and geochemical differences between intrusions, more study needs to find the interval phases. Emplacement of these intrusions are related to calk alkaline subduction of Arabian plate with Central Iran plate, and obtained data, could assist on timing of offered tectonomagmatic models.
N Abrari,
Volume 10, Issue 2 (2-2010)
Abstract

The study of planktonic foraminifera of the Gurpi Formation in southwest of Firozabad(Aghar anticline) area led to recognition of eight biozones that include: Dicarinella asymetrica Zone (Santonian to Earliest Campanian), Globotruncanita elevata Zone (Early Campanian), Globotruncana ventricosa Zone (Mid to Late Campanian), Radotruncana calcarata Zone (Late Campanian), Globotruncanella havanensis Zone (Late campanian), Globotruncana aegyptiaca Zone (Late to Latest Campanian), Gansserina gansseri Zone (Latest Campanian to Early Maastrichtian), Contusotruncana contusa and Racemiguemblina fructicosa Zone (Early to Late Maastrichtian). In study area, the Gurpi Formation overlies the Ilam Formation with erosional disconformity and is overlain by the Pabdeh Formation with erosional disconformity. Based on distribution of morphotype groups of planktonic foraminifera, planktonic foraminifera per bentic foraminifera ratio(P/B) and content of carbonate, seven third-order sequences are recognized. Sequence boundries of Gurpi Formation with Ilam Formation at the base and with Pabdeh Formation at the top, are SB1, but other sequence boundries are SB2.
, ,
Volume 10, Issue 2 (2-2010)
Abstract

Abstra
Every year a large number of boreholes are drilled in various areas of Isfahan city and numerous tests are undertaken to determine the characteristics of engineering geology of Quaternary deposits. However due to a lack of organized plan the results of these geological tests are not unfortunately used in next projects.
Nowadays, geotechnical data banks in different countries have already led to a computerized and organized plan. This project aimed to make a database in the third traffic zone in Isfahan Through the retrieved finding in various drilled boreholes of civil engineering projects. The database includes 300 boreholes features, 11093 records and 38 fields.
The access, which has capability of special search, has been utilized, then data were analyzed by Surfer and a variety of specified map were drawn. . Statistical method to analyze the data was inverse distance to power.
Based on such maps, the geological characteristics of Quaternary deposits were examined the soil of studied area is most inactive. The depth of bed rock south to north increased. Therefore, regarding to borehole data it is possible to recognize the fault in some part of Isfahan city
To earn quantities and qualities results upon geological characteristics of alluvial deposits, the development of database is recommended.
Bahman Soleimani,
Volume 10, Issue 2 (2-2010)
Abstract

The Shadgan petroleum oil field located in Dezful Embayment is a symmetrical anticline with 23.5Km length and 6.5Km width in the Asmari top horizon. The field trend is similar the regional Zagros trend. Asmari reservoir consisted of two separated reservoirs. The aim of the present study is to construct stratigraphy and faults models, reservoir quality evaluation, fault impacts and oil volume determination using RMS software. To construct the structural model, faults and reservoir zones data will be applied to design reservoir geometry. Stratigraphic and fault models revealed that the faults passed through the reservoirs but have not affected on their relations. This fact is verified by different petroleum API in two reservoirs and their independent pressure variations as well during production period. With correlation of faults, porosity distribution and reservoir volume models, it was revealed the fault effects in the reservoir properties quality.
, S Karimi,
Volume 10, Issue 2 (2-2010)
Abstract

Abstra
The metapelites of North of Golpayegan show that these rocks can be divided into four categories based on mineral assemblages: chloritoid- garnet- biotite- schist, garnet- biotite- muscovite- schist, staurolite bearing garnet- biotite- muscovite schist and Kyanite bearing staurolite- biotite- muscovite- schist.
The appearance of chloritoid in chloritoid- garnet- biotite schists shows green schist facies. Garnets in garnet- biotite- muscovite schists shows 3 stage of growth and syn-tectonic formation.
The appearance of staurolite in staurolite bearing garnet- biotite- muscovite schists signifies the beginning of amphibolite facies. The absence of zoning in the staurolite contained in these schists suggests the formation and growth of this mineral in a prograde metamorphism.
The thermodynamic study of these rocks shows that North of Golpayegan's metapelites were formed within a temperature range of 480 – 560oC and a pressure range of 1.6 – 4.1 kbar. These results are consistent with the minerals' paragenetic evidence and show that effect of metamorphism on North of Golpayegan's pelitic sediments is to lower amphibolite facies (Epidote amphibolite).
, ,
Volume 10, Issue 2 (2-2010)
Abstract

توده های گرانیتی منطقه زریگان و چاه چوله در شمال بافق، جنوب شرقی نقشه 1:250000 اردکان واقع شده (شکل 1)، جزیی از خرده قاره ایران مرکزی محسوب می شوند. ترکیب سنگ شناسی این توده ها، از آلکالی فلدسپار گرانیت تا سینو- مونزو گرانیت نوسان دارد. آنها از نوع گرانیت های لوکوکرات و ساب ولکانیک، با کانی شناسی عمدتاً کوارتز- فلدسپاتی، و فقیر از کانیهای مافیک هستند. انواع بافتهای ماگمایی، دگرشکلی، متاسوماتیک و دگرسانی، گرانوفیری، گرافیک، میلونیتی و کاتاکلاستی، میرمکیت، پرتیتی و جانشینی در آنها دیده می شود. از نظر ژئوشیمیایی، توده های مورد بحث، ویژگیهایی از سریهای کالکوآلکالن تا آلکالن، پرآلومینI-type و محیط تکتونیکی کمان ماگمایی را نشان می دهند. در نمودارهای تغییرات عناصر نیز، بستگی به تمایلات ذاتی، پویایی و مراتب سازگاری و ناسازگاری عناصر، رفتارهای متفاوتی دیده می شود که گویای تاثیر فرآیند تفریق و تبلور و متاسوماتیسم، هر دو، بر توده های مذکور است. شواهد صحرایی، سنگ شناختی و ژئوشیمیایی، در توده های گرانیتی زریگان و چاه چوله حاکی از آن است، که لااقل بخشی از این توده ها، بویژه گرانیت زریگان، از طریق متاسوماتیسم و فرآیندهای تفریق گرمابی از سنگهای مافیک قبلی (توده های دیوریتی و گابرویی) تشکیل شده است و حتی پس از آن نیز به نحوی گسترده تحت تاثیر این فرآیندها واقع شده اند. مقایسه این توده ها، با معیارهایی که برای تمایز گرانیت های ماگمایی و متاسوماتیک ارائه شده، نشان داده که این توده ها، ضمن شباهت هایی با برخی از توده های شاخص ماگمایی، بیشترین شباهت را به گرانیت نوع متاسوماتیک یا
E- type دارند.
Amir Eskandari, F Masoudi, N Farahkhah,
Volume 12, Issue 2 (11-2012)
Abstract

In this research, based on spatial distribution and size of crystals, the role of physical processes affecting formation of the igneous rocks such as kinetics of crystallization (nucleation and growth of crystals), dynamics of magmatic systems (e.g. mixing and convection currents) and equilibrium processes such as textural coarsening are investigated.
To this end, the spatial distribution pattern (SDP) of plagioclase, amphibole and quartz crystals were quantified in the microdiorite-quartz diorites and results were combined with petrography to discuss the factors affecting plagioclase packing arrangements and physical processes operated during formation of these rocks. The study area is located in 120 Km southeast of Birjand. The 8 thin sections of rocks were processed and geometrical features e.g. length, width and centre of 3098 crystals were measured. Then, R values (a descriptive value) were measured using nearest neighbor distance method with BigR and ArcGIS software's and the data were plotted against porosity (modal abundance of other phases in igneous rocks.) Results show that crystals have clustered SDP. The degree of plagioclases clustering is different in sections with change of crystal sizes and shapes. The origin of crystal clusters is likely to involve heterogeneous nucleation, textural coarsening and overgrowth of crystals.
Sahand Tadbiri, Mahmoud Almasian, Mohsen Pourkermani,
Volume 12, Issue 2 (11-2012)
Abstract

Introduction and purpose : Chah-Savar-Agha quarry, the quarry which belongs to Neyriz marble quarries complex, is one of the important economical center in the Fars province. In recent years, some slumps and instabilities have occurred in this area and this phenomenon increases the importance of structural studies and investigation of tectonic stress specially insitu stresses. Therefore, the main purpose of this research is the investigation the role of tectonic structures such as joints, fractures, insitu stress phases and effects of them on instabilities of the northern slope.
Method :
By field studies and measurement the geometrical characteristics of the fractures, including dip and dip direction of joints, fillings and the number generations of filling, they are analysed by DIPS5.1 software to achieve the structural analysis and reach to the insitu stress phases.
Results :
According to the results, at least two insitu stress phases are acceptable in the area.
- Releasing stress phase : this stress phase with the South West- North East trend has caused the reactivation of some old joints and creation of some young fractures in the area. The releasing stress phase has been created by rapid extraction from the quarry.
- Local tensional phase :
Field observations have indicated that the Northern slope was creeping in the North East direction and this phenomenon has created the tensional stress phase with the East- West trend in the area and this stress phase has created some vertical fractures with the North-South trend also.
The creep mechanism in the Northern slope has been created by burden of debris which have been accumulated on the top of Northern slope.
Burden of these debris has created the vertical stress that has caused the creep mechanism upon a fracture with N152/50NE identity in the South East Strike.
, , Mohammad Mohajjel,
Volume 12, Issue 2 (11-2012)
Abstract

The Alut granitoid complex is located in the northwestern part of the Sanandaj–Sirjan zone. This complex comprises three main units i.e. monzogranite to granodiorite bodies (SiO2 = 65–77 wt %) which is widespread throughout the area, a quartz-diorite to tonalite unit (SiO2 = 52–63 wt %) exposed as two stocks and mylonitic granitoid scattered as separate outcrops through the area. NE-SW trending microquartz-diorite and NW-SE trending aplite dykes are also present in this complex. The quartz-diorite to tonalite unit has relatively high CaO,FeO, MgO, Al2O3 and low Rb/Sr, Sr/Y, and (La/Yb)N, which preclude an origin of variably fractionated mantle melts and favour a mafic lower crustal source. Dehydration melting of biotite-bearing metasedimentary sources at relatively low pressures is proposed for the origin of monzogranite to granodiorite unit. Geochemically this complex is metaluminous to slightly peraluminous, typical of I-type granites. It belongs to low K (and high K for some monzogranite samples) calc-alkaline series and displays the geochemical characteristics typical of volcanic arc plutons related to an active continental margin area (e.g. significant Nb, Ti, P and Sr depletion). Based on collected geochemical data, the Alut granitoids originated by partial melting of crustal protoliths having different compositions in a deformed active margin.
S. A. Alavi, M. R. Ghasemi, M. Mokhtari, A. R. Gelalzadeh, Reza Alipoor,
Volume 12, Issue 2 (11-2012)
Abstract

The Pazanan oil field is located in Dezful embayment, 150 km south east of Ahvaz and south east of Aghajari oil field. Aghajari formation has formed surface outcrop and also the Asmari formation with 7 reservoir layers is the main reservoir rock in this oil field. In this research high fractured areas in the Pazanan oil field have been analyzed based on subsurface date and utilization of subsurface analyzes method. It seem to be the Pazanan oil anticline is an asymmetric fold with high dip in south west limb and the middle parts have been distinguished as areas with potential of fractures development with respect to longitudinal Curvature. Geometrics analysis of this structure indicate that south west limb in more parts and north east limb in middle parts have been distinguished as areas with high fractures density. Axial bending (longitudinal) of the Pazanan anticline is because of growth and propagation and combining of separate anticlines shear zone result of strike slip faults motion and old strike slip structures.
Bahman Rahimzadeh, Jamshid Hasanzadeh, Fariborz Masoudi,
Volume 13, Issue 4 (2-2014)
Abstract

Gabbroic stocks and dykes associated with Ophiolitic Basalts and peridotites are outcropped in the Sawlava town area. Sawlava ophiolite is part of Kurdistan Ophiolitic complex that located in sheared zone between high Zagros and northern Sanandaj-sirjan Zone. This study focused geochemistry and dating of granular and pegmatoid gabbros that due to closing to main recent fault (MRF) some part of them found milonitic fabric. Gabbros have 47.84 to 51.65 percent SiO2 and almost formed from tholeiitic magma. Labradorite plagioclase and diopside and augite clinopyroxens with Mg# of 83.90 to 88.90 respectivly are main minerals of gabbros. Based on geochemical and geotectonic diagrams, gabbros generated from slightly deplete magma which formed in back arc supra-subduction zone. U-Pb dating of zircons presents an average age of 38.3±1.3 Ma for gabbros. Late Eocene age from Sawlava gabbros and similar gabbros bodies related to ophiolites along Zagros suture, could indicate that neo-tethyan ocean closed after Eocene in the Kurdistan region.
E Moradian Teshnizi, Mostafa Ghomashi, Ali Ahmadi, Hadi Aminrasoli,
Volume 13, Issue 4 (2-2014)
Abstract

The study area is located to the south, west and north Esfahan province. this research is geochemical and petrographic study of Lower cretaceous dolomites. Five dolomite type have been identified.
The first type is very fine-fine crystalline dolomite formed in near surface conditions and in early stages of diagenesis, in tidal flat to lagoonal environments. The Sr content is high (2537ppm) and Fe (8861ppm) and Mn (852ppm) is low.
The second type is fine-medium-grained, subhedral to euhedral, crystalline dolomites. Compared to the first type, Sr content is lower and Fe and Mn content is higher. This type of dolomites is most likely formed in early burial diagenesis.
The third type is medium-coarse-grained, euhedral and subhedral, crystalline dolomite and show clear rim and cloudy center. Compared to the type1 and type2, this type of dolomite contains higher Fe and Mn and lower Sr. They are likely formed in deeper burial diagenesis and by dolomitization of earlier calcareous deposits or recrystalization of first- and second- type dolomites.
The medium-coarse-grained, crystalline dolomite fill in pores and fractures, and are called "four-type" in this study. This type of dolomite is likely formed during late diagenesis and under conditions of medium pressure and temperatures less than 60-80 °C. In this dolomite values of Fe and Mn increase from the fringes of pores and fractures to the center.
The fifth dolomite type is coarse, crystalline, saddle dolomite filling pores and fractures. This dolomite
Faribourz Masoudi, Roghieh Doroozi,
Volume 13, Issue 4 (2-2014)
Abstract

In the northern hillside of Central Alborz, in south Marzanabad, there are outcrops of basic volcanic rocks which attributed to Cretaceous time .In this study, effective processes on evolution of these volcanic rocks are surveyed to add on our knowledge about Mesozoic magmatisim in Central Alborz. Based on petrographical and geochemical studies, south Marzanabad basic rocks could be classified into 2 groups of basalt and andesite basalt. Geochemical diagrams imply that the magma nature is alkaline and generated in intracontinetal extensional environment. Microscopic studies, mineral chemical composition and the observed trends in geochemical diagrams of whole rocks, all are inline with fractional crystallization as a main magmatic process. Fractionation began with crystallization of olivine and pyroxene and minor plagioclase in basalts and continued with crystallization of clinopyroxene and plagioclase in andesite basalt. In addition to petrographical, mineralogical and chemical evidences, the occurrence of fractional crystallization process is confirmed by the geochemical modeling with Melts software which also let us to reconstruct the condition of fractionation process. Based on the fractional crystallization modeling in south Marzanabad basic volcanic rocks, basalts are generated by 40 percent of fractional crystallization from primary magma. Basaltic andesites also produced after the fractionation of basalts, during 70 percent fractional crystallization from the same magma. Olivine thermobarometric studies also confirm the accuracy of data which is obtained by the Melts software.
Hamid Nassery, Rouhollah Adinehvand, Abdalrahim Salavitabar,
Volume 13, Issue 4 (2-2014)
Abstract

Tabriz plain with area of 869 square kilometers is a part of the Urmieh lake's catchment. The purpose of this study is to simulate the behavior of Tabriz aquifer against various stresses and determine the permissible level for the operation of the aquifer. To achieve the above objective the system dynamics simulation method has been used.
In this regard, the required information includes ground water resources data (wells, springs, qanat), sources and consumptions after analysis to eliminate defects was given to the VENSIM PLE+ software, and a dynamic simulation model was developed. Then by define the range of allowed water table fluctuations and the allocation of extracted water under these conditions, the allowable water level and safe yield of the aquifer was determined.
According to the obtained results in the six-year modeling period, the maximum amount of monthly and annual extraction without any damage from the aquifer is 12.70 and 152.45 million cubic meters respectively. The average of minimum and maximum allowable water table level during this period are 1317.35 and 1322.34 meters respectively.
Nematollah Rashidnejad Omran, Maryam Nadri, Mehraj Aghazadeh,
Volume 13, Issue 4 (2-2014)
Abstract

The granitoid intrusion trending NW-SE, is expose in the East of Zanjan, structurally located in the Alborz - Azarbaijan zone and Tarom sub-zone. Petrographic composition of the intrusion includes a range of monzogranite, quartz-monzonite, quartz-monzodiorite to monzodiorite and in fact shows monzonite series composition. The major rock forming minerals consist of K-feldspar, plagioclase, pyroxene (augite-diopside) and quartz. They show granular, intergranular, microgranular to porphyrytic-microgranular textures. The intrusion has metaliminus high-K calc-alkaline to shoshonitic and I-type affinity. Enclaves of the intrusion have micro-granular mafic and monzodiorite, quartz monzodiorite composition, which are fine-grained than their host rock and have micro-granular porphyritic texture. According to the petrographical and geochemical studies, the magma has originated from partial melting of metasomitised sub-continental lithospheric mantle due to fluids and/or partial melts that originated from subduction edge. According to Harker Diagrams seems that monzodiorite magmas differentiation Leads to monzonite Formation And finally the Crystallization and differentiation are monzogranite. Therefore Crystallization and differentiation are the most important processes controlling rock types in the monzonite series intrusion. Tectonic diagrams indicate a continental margin magmatic arc and syn-to-post collisional intra-arc extensional environment.
Ali Yasaghi, Azin Imanpur,
Volume 13, Issue 4 (2-2014)
Abstract

Anbaran inlier is located at the NW of Namin city. In the inlier Pre-Paleozoic roks surrounded by young Eosen and Cretaceouse rocks.To interpret the inlier deformation and its evolution model, geometry as well as kinematic characteristic its major structurs analysed for the first time. For the faults kinematic, indicator, such as slickenside, fault associated folds and S-C structure were used. The results of analysis show that the major structurs of inlier are the Anbaran and RF1 fault at its Norht and South margins.The high angle Anbaran and RF1 faults cause thrusting of the Pre-Paleozoic Biandor and Soltanieh formation in the core of inlier over the Eocen volcanic units and Cretaceouce limeston respectively.This resulted in development of a pop-up structure that form the present morphology of the region .The fault high angele dip, and deposition of Cretaceous sediments on its hanging wall provide evidence for the fault inversion.therefor the RF1 fault is considered as the inverted anbaran fault backthrust.
Mehraj Aghazadeh, Adel Sarkhoshi, ,
Volume 16, Issue 41 (5-2015)
Abstract

In the North of Bam city there were extensive volcanism and outcrops are basic and felsic volcanic rocks that crosscut by various dykes The volcanic rocks have sub alkaline and calc-alkaline to shoshonitic characteristic, however dykes are alkaline and potassic in nature. In the spider diagram all samples show enrichment in the LILEs and depletion and troughs in the HFSs elements that coincide with subduction related and upper crust rocks features. The studied samples represent enrichment in the LREE with various (La/Yb)N ratio and rhyolites show clear trough in Eu. According to geochemical features, studied rocks generated from different sources. Trachy andesy basalts and trachy andesites formed from 1-10% partial melting of metasomatized spinal lherzolite source. Dacitic magma generated from partial melting of mafic source in the lower crust while rhyolites formed from partial melting of metagreywacke source. The olivine basaltic and basaltic dykes generated from less than 1% and 3-5% partial melting of metasomatized garnet- spinel- bearing lherzolitic mantle source, respectively. Eocene volcanism in the Bam area has been occurred during subduction of Neo-Tethys oceanic crust beneath central Iran in the continental volcanic arc tectonic setting.
Fazel Iranmanesh, Mehran Maghsoudi, Ebrahim Moghimi, Mojtaba Yamani, Amir Hossin Charkhabi,
Volume 16, Issue 41 (5-2015)
Abstract

Deltas of the most important morphological units are a tremendous effect on agricultural activities, mining, coastal management and etc. Despite appropriate soil and water resources deltas, are influenced by environmental phenomena such as climate change and sea level changes. The effect of these changes will appear on physico-chemical, mineralogical deposits. This study was conducted to analyze the Karkheh delta depositional environments based on the chemical characteristics of ancient sediments. Depositional environments and locations of core were identified using digital data processing, geomorphology mapping and initial visit of the area. The coring was carried out with rotary drilling machine and continuously to a depth of ten meters in jofeir and Rofayeh. Among The cores, 20 samples were selected for mineralogical and chemical tests. Differences in chemical and mineralogical characteristics revealed at least three major discontinuities exist between sedimentary layers to a depth of 10 m. In addition, thickness and type of the sediment are not same conditions and it changes depending on the stability of depositional environments. Increasing of Mg / Ca, magnesium and salinity, and reducing of clay particles, show Sedimentary environments trend is toward dry conditions and high energy environments at depths from 10 to 5 meters. In contrast, the depth of 5 to 4 and 3 to 0 meter this trend towards more humid climate and low energy environments. Therefore, it is concluded that the depositional environment of the Karkheh River delta at the upper Holocene is not constant, and this has led to changes in the delta.
,
Volume 16, Issue 41 (5-2015)
Abstract

The Almabulage complex is located in the Sanandaj-Sirjan structural zone, NW of Hamadan. This complex consists of low-grade metamorphic rocks, and two intrusions of felsic and mafic rocks. In this research, we have studied the mafic intrusion. The intrusion has ophitic, subophitic and inter-granular textures and is mainly composed of plagioclase, clinopyroxene, amphibole and minor amounts of K-feldspar, quartz and opaque minerals. Secondary minerals include epidote, chlorite and amphiboles formed in the rim of clinopyroxene. Clinopyroxene is of augite type, amphibole is tschermakite, plagioclase is in the range of andesine-labradorite, k-feldspar is anorthoclase and the opaque mineral is ilmenite. According to the bulk rock geochemistry and mineral chemistry of clinopyroxene, the mafic intrusion of the Almabulage complex has been crystallized from a calc-alkaline magma and is related to subduction area. The element Nb displays distinctive negative anomalies compared to the primitive mantle, which can suggest subduction-related magmatism. Emplacement temperatures and pressure of mafic rocks shown by pyroxene-amphibole thermometer and amphibole barometer indicate temperature and pressure ranges of 750 to 900 °C and 6 to 7 kbar, respectively.
Based on Sm/Yb and La/Sm rations, the parental melt of the mafic rocks of the Almabulage complex, derived from partial melting of garnet–spinel lherzolite. According to the bulk rock geochemistry and mineral chemistry of mafic rocks, the rocks formed in a subduction area during Late Jurassic-Early Cretaceous before the Neo-Tethys closure in Sanandaj- Sirjan zone.

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