GEOSCIENCES
Year:2019 | Volume:28 | Issue:110 |Papers Count:36

The Early Cretaceous Eastern Haft-Savaran Zn-Pb (Ba) deposit situated in the Arak mining district and occurred within the extentional back-arc of Malayer-Esfahan basin. Mineralization occurred in two horizons in the Estern Haft-Savaran deposit. First horizon is major horizon that formed within the most upper portion of the massive limestone and second horizon occurred in the thin limestone which is alternate with shale and marl. Textures of the mineralization in this deposit are replacement, massive and vein-veinlets, and main alterations are silisification, dolomitization and calcitization. Sphalerite, galena, chalcopyrite, tetrahedryte, pyrite, bornite, chalcosite and covelite are the sulfide minerals and quartz, calcite, dolomite and sericite are gangue minerals in the ore deposit. Cathodoluminescence study in this deposit indicates three dolomites and one calcite generations. First generation of dolomite associated with weak mineralization and second generation of dolomite is Fe-rich and associated with main mineralization. Third generation of dolomite is late dolomitization and formed with calcite and cross-cutted the mineralization. Presence of framboidal pyrite with galena and sphalerite in its matrix and fine-grain euhedral barite suggest mineralization began during sedimentation and early diagenesis stage near seafloor. In continuum, main ore is identified as replacement occurrence of first generation sulfides by second generation coarse-grained sulfides under seafloor. With regarding to the formation of the Eastern Haft-Savaran deposit in the extentional tectonic setting, massive limestone as the host rock, and mineralization formation as replacment during diagenesis of the host rock under the seafloor, this deposit would be classified as Irish type deposit.

The Qatar-Cowbandi arc is a giant regional anticline with northeast-southwest direction, runs through the Qatar peninsula, extends northeastward through the Iranian sector of the Persian Gulf. The arc in the Iranian part is subject of the study meditation. In this paper the interpretation of 2D seismic in the interval of top of Laffan to top of Jahrum formations, allows the regional research of the arc in the study area. Seismic interpretation in both horizons have distinct indications for existing a platform in the area with northwest-southeast direction, which smoothly dipping toward northeast, with some highs resulted from salt diapirs activity. According to isopach map provided for sedimentary sequence of Ilam-Jahrum formations, which was prepared based on 2D seismic data, the sediments thickness decreases in the platform area. The platform is interpreted as crest of arc, on which low rate of sediment precipitation occurred due to low accommodation space, resulted from the arc uplifting activity. Therefore, the arc and also salt diapers, should be considered as regional important factor in sequence stratigraphy study for the precipitated sediments.

There are two different seismotectonic zones in around of the Zendan-Minab-Palami (ZMP) fault system and the Oman Line, in south of Iran (Makran subduction zone in the east and Zagros collision zone in the west), which led to the complexity of this region. Since studying the stress field is important for accurate perception from elastic features of environment, surveying the exerted the tectonic stresses to the tectonics plates and their magnitude, and description the geodynamic of this region, in this study considerd to assessment of stress field and also, maximum horizontal stress (SH) in around of ZMP fault system. To receive this purpose, amount and direction of stress is calculated by iterative joint inversion of earthquake focal mechanism. From east to west of ZMP fault system, with transition from Makran subduction to Zagros collision, direction of SH is reduced from 5. 09º in east to 0. 9º . To surveying the strain field, we used Global Positioning System (GPS) data. Maximum variance between velocity vector and direction of SH is determined in Bandar-Abbas (BABS) station, that located in adjacent of ZMP fault system. The friction coefficients which obtained in this study show that friction in Makran zone is more than Zagros zone.

Khalyfehlou Cu deposit (southeast of the Zanjan), is the volcanic-hosted vein-type deposit located in the Tarom metallogenic zon, Western Alborz (northwest of Iran). Tarom zone consist mainly of volcanic and volcaniclastic rocks of the Karaj Formation (Early to Middle Eocone). Regarding the stratigraphic position, the Karaj Formation is divided into two members: Kordkand and Amand. The Kordkand member is overlain by the Amand member. The Amand member is divided into six units, Ea1 through Ea6. The Khalyfehlou Cu deposit is located in Ea5 and Ea6 units of Amand member. The Karaj Formation is interrupted by large and linear intrusions with calc alkaline affinities. Host rocks are green tuffs and, rarely, andesites. The patterns of rare earth elements in the studied samples indicate the negative anomaly of Eu element due to plagioclase subtraction. In all the samples, the enrichment of light rare earth elements (LREE) and large lithophil ion (LILE) elements and the depletion of strong field strength elements (HFSE) are observed. This probably indicates the common origin of these rocks. Main minerals include chalcopyrite, bornite, chalcocite, and covellite and gangue minerals including quartz, sericite, and calcite. In this paper the origin of ore-forming fluids and genesis of Khalyfehlou Cu deposit is studied using sulfur and oxygen isotope data. The sulfur isotope values for the chalcopyrite range from − 2. 0 to − 5. 3‰ . Negative sulfur isotopes values and the occurrence of framboidal pyrite in the tuffaceous sandstone host rocks suggests a sedimentary origin for the sulfur. The oxygen isotope composition of quartz from the veins ranges from 12. 3 to 14. 3‰ . The δ 18Ofluid values calculated from the oxygen isotope data range from 0. 6‰ to 3. 6‰ . The O isotopic characteristics indicate that the ore-forming fluids for the Khalyfehlou deposit was meteoric-formational water. This study suggests that mineralization at the Khalyfehlou deposit is similar to cordilleran vein-type deposits.

To study intraformational flat pebble conglomerates of the lower member of the Elika Formation (Lower Triassic), four stratigraphic sections in the Alborz Mountains of northern Iran were selected. The thickness of the lower member of the Elika Formation in these sections ranges from 95 meters in the type section to 195 meters in the Veresk section. This member mainly consists of heavily bioturbated thin to thick-bedded limestone and shale intercalations which deposited under fair-weather and storm conditions. The intraformational flat pebble conglomerates are the most important of the storm facies. These conglomerates have sharp or erosional bases and interbedded with the fair-weather facies. These facies rang from a few centimeters to 100 cm thicknesses, and mainly consist of gravel-size intraclasts. The intraclasts are horizontal to sub-horizontal in the thinner beds, but they are imbricated, sometimes opposing orientations in the thicker beds. Their textures are mainly rudstone and sometimes floatstone. Field and microscopic studies indicate that the intraformational flat pebble conglomerates were deposited by powerful storm generated flows in open marine, shoals, lagoon and tidal flat/ beach ridge sub-environments related to carbonate homoclinal ramp platforms.

The Zarshuran gold deposit in northwest Iran is located in historic gold and arsenic mining area in the Sanandaj-Sirjan geo-structural zone. This area is mainly composed of Precambrian rocks. The Oligo-Miocene granitoid intrusions in Pre-Cambrian formations which are the country rocks of gold mineralization have resulted from intensive alteration, milonitization and gold mineralization. The main aim of these study is the separation of gold mineralization zones by using concentration-number (C-N) and concentration-volume(C-V) fractal techniques, which is based on 44 drill hole data and 5800 analyzed samples. Firstly, the logarithmic graph of gold was plotted for each model. Five gold mineralization zones were identified by using concentration-number model and four zones with concentration-volume model, indicate that intense of gold mineralization in wall rock, weak, medium, high and highly enriched zone, respectively. 3D geologic and fractal models show that low mineralized zones occurred in most of the ore deposits, which are often related to the Iman-Khan rock unit. In addition, based on fractal model interpretations and calculation of the overall accuracy matrices, these regions with medium, high and enriched zone have good overlaps to the Jasperoid rock unit, Chaldagh limestone, and Zarshuran shale units, respectively.

The Alvand batholith is located in the south of the Hamedan city and in the northern part of the Sanandaj-Sirjan metamorphic zone. Porphyroid granite, quartz diorite and diorite are formed rock members of the mesocratic granitoids in the Alvand plutonic complex. Porphyroid coarse-grained granites make up the main volume of the Alvand bathilith. For study of minerals chemistry and thermobarometry of the mesocratic granitoids of the Alvand bathilith, microprobe analyses were carried out on the orthoclase, plagioclase and biotite in the porphyroid granites and were carried out on the amphibole, plagioclase and biotite in the quartz diorites and diorite. Mineral chemistry study shows that amphiboles in the quartz diorites are often of the magnesio-hornblende type and in the diorite are magnesio-hornblende and tschermakite type. Plagioclases in the porphyroid granite are albite and oligoclas type, in the quartz diorites are oligoclas and in the diorite are andesine type. Biotites in the mesocratic granitoids of these rocks are primary type and they are filled in the annite area. Results of thermobarometric study show that average of P-T conditions of amphibole crystallization in the mesocratic granitoids of the Alvand batholith are ~787 oC and ~1. 46 Kb. Results of biotite thermobarometric study estimate that average of temperature and pressure of biotite solidification in mesocratic granitoids of the Alvand batholith are ~ 679 oC and 1. 56 Kb. According to the pressure formation (~1. 5 Kb) of the Alvand batholith, depth of its emplacement is estimated ~ 4. 7 Km.

Haftkel and Masjed-I-Soleiman oilfields, setting in Dezfool embayment at Zagros Basin, are the most important oilfilds in south-western Iran. Asmari Formation, the most famous reservoir in the Middle East, is reservoir of these oilfields. In order to palaeoenvironments and sequence stratigraphy correlation, the subsurface sedimentary successions of the Asmari Formation have been studied using cores and thin sections obtained from the well no. 28 of Haftkel and well no. 186 of Masjed-I-Soleiman oilfields. 18 carbonate and 1 carbonate/evaporate microfacies and 2 noncarbonated microscopic facies were recognized, based on petrographic study. These microfacies and microscopic facies were grouped in 6 facies associations (include: Tidal Flat, Lagoon, Bar, Restricted marine, Open marine, and Mid ramp). Obtained facies associations, comparing them with standard facies models and statistical analyses, indicate that Asmari Formation was deposited in the inner and middle of a homoclinal carbonate ramp. Correlating Asmari association facies in Haftkel and Masjed-I-Soleiman oilfields showed that Haftkel oilfield has been in the shore-ward and Masjed-I-Soleiman oilfield has been in sea-ward of that ramp. Sequence stratigraphy studies express that the succession of Haftkel oilfield could be discriminated to six third order deposition sequences (Sq1-Sq6). Incorporation of the sequence stratigraphy criteria of Asmari successions in this oilfield with its previous biostratigraphy data reviles that Sq1 and Sq2 occurred during Aquitanian time and Sq3 to Sq6 during Burdigalian age. Correlating of Asmari sequences of this oilfield with the Asmari sequences of Masjed-I-Soleiman, based on cyclostratigraphy data, show the sequences of Masjed-I-Soleiman occurred in Burdigalian time. Also the correlation expresses the steep of proposed ramp was toward Masjed-I-Soleiman area. The sequence correlation with global sea level fluctuations shows Burdigalian depositional sequences occurred based on eustasy in these oilfields.

There are several outstanding factors engaged in the cement grouts filtration. These factors can be evaluated from some aspects including the characteristics of the grout, cement and grouting materials, grouting environment, interaction between the grout and environment and grouting pressure among which fewer studies have been performed on the role of the grouting pressure in the grout filtration. In this research practical results of cement grouting have been reviewed in two dam projects as examples. The results depict that the increase in the grouting pressure considerably affects the rate of cement take and penetration. In practice, the cement penetration rate into the rock is higher when the grouting pressure is variable. This is vice versa under constant grouting pressure. In other words, the increasing steps of grouting pressure may erode the grout cake at each stage. This leads to optimal penetration of the grout and decreases the watertightening costs of the dam foundation, tunnels and structures requiring cement grouting.

Tashvir ore occurrence, 75 km northeast of Zanjan, is located in the Tarom-Hashtjin subzone. Mineralization occurs as ore-bearing quartz vein-veinlets within the Eocene tuffs and andesitic lavas (equal to Karaj Formation). Ore minerals include chalcocite, chalcopyrite and galena, and quartz, calcite and chlorite are present as gangue minerals at Tashvir. The ore show vein-veinlets, breccia, disseminated, replacement, relict, colloform, crustiform, dog tooth and plumose textures. Four stages of mineralization can be distinguished at Tashvir. These stages are progressed from quartz-chalcocite-chalcopyrite-galena‒ cemented veins and breccias (stage-1), individual or sets of quartz veinlets (stage-2), and vug infill calcite (stage-3) and chlorite (stage-4) vein-veinlets. Hydrothermal alteration consist of silicified, argillic, carbonatic and chloritic. In the outer parts of the mineralization zones, alteration is propylitic. Similar REE patterns of the mineralized veins and the host rocks indicate they are genetically related. Enrichment of ore-forming elements (Ag, Cu, Pb, Zn) in ore zones is specifies leaching of elements from altered host rocks to ore zones. Characteristics of Tashvir ore occurrence are comparable with intermediate-sulfidation style of epithermal base metal (Ag) deposits. Mineralization at Tashvir and other epithermal deposits of the Tarom-Hashtjin subzone took place as a result of hydrothermal activity related to the late Eocene magmatism, and is controlled by fault systems. Therefore, investigation of the altered Eocene volcanic and volcano-sedimentary rocks, especially at the composite place of granitoid intrusions and along the fault structures, became the most favorable locus for epithermal ore bodies at Tarom-Hashtjin subzone.

The main purpose of this paper is studying sedimentary layer in the Qeshm Island. We use aftershocks of 27 Nov. 2005 Qeshm Island (Mb=6. 0), to perfume 2D tomography of Rayleigh waves. We have analyzed surface wave data for 856 aftershocks, consist 9821 waveforms. The dispersion curves are calculated in the period range between 0. 1 seconds and 10 seconds, which correspond to the shallow structures of uppermost crust including sedimentary layer. Surface wave tomography has also been performed to estimate the two-dimensional group velocity maps of Rayleigh waves in the region. The isolated surface wave fundamental modes by Herman and group velocities dispersion curves obtained by it, using Yanovskaya-Ditmar linear inversion method for estimation of 2D tomography maps. Based on the ray coverage, the area divided into cells with dimension 1 Km ×1 Km. in every cell and for distinct periods the velocities were calculated. The minimum dimension of distinct heterogeneities estimated as about 3 km. Low-velocity anomalies in tomography maps can be related to the accumulation of salt plugs and some soft sediment in the area. In periods up to 4 sec, which related to shallower depths, a distinct lineation observed that may relate to a fault. It seems that this fault has cut off the sediments. Into the deeper sediment, this fault disappeared which means the sediments were softer and unbreakable.

Image logs of 14 wells in the 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, the NE-SW trend fracture sets are more developed by reactivation of Hendijan basement fault. Convergence of stress axises as a result of the fault interaction of the 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 the Rag sefid anticline.

Taleh Zang Formation is shallow carbonate facies of the Paleogene Zagros Basin. According to the area, including depth, tectonic and sedimentary sedimentation rate and other factors of the formation with Kashkan and Shahbazan sometimes with different thicknesses of semi-deep and deep Papdeh facies were deposited locally. According to the study Taleh Zang Formation calcareous stratigraphic section thickness of 185 meters (true thickness) were measured from 15 genera and 10 species of 110 sample benthic foraminifera identified by study and introduced 3 biozones 2 Assemblage zone and a Acrozon, late Paleocene (thanetian) and lower Eocene (ypresian) is intended for the stratigraphic section.

Investigating of dolomitization and its effects on reservoir quality of the Upper Dalan Formation with Permian and Triassic in age is the aim of this study. In this section, the Upper Dalan Formation consists of carbonates and evaporite rocks with a thickness of 265m. Eleven carbonate-evaporate microfacies have been distinguished on the basis of depositional textures, petrographic analysis and present fauna. These microfacies were deposited in three facies belts including tidal flat, lagoon and carbonate shoal. Absents of turbidite (calciturbidite) and tempesties deposits, slump structures, large barrier reef, widespread tidal flat and lagoonal facies with aboundent of mud matrix indicated that depositional setting of this interval was a homoclinal carbonate ramp. Based on petrographic studies, 4 types of dolomite including dolomicrite, dolomicrosparite, dolosparite and dolomite cement are recognized. Porosity and permeability data in varies dolomites reveals that in most dolomite the amount of permeability is not directly related to whole porosity, but depends mainly on the amount of connected porosities through bottleneck holes and is associated with increasing in dolomite crystal sizes. Therefore, from the early stage of dolomitization in the form of dolomicrite toward increasing in the rate of dolomitization with larger crystal size and with the form of subhedral and euhedral crystals, the reservoir properties had a high visible improvement. Ultimately, by persisting of dolomitization and growth of dolomite crystals toward each other and disappearance of bottleneck holes and creation of dolomite cements, reservoir properties destroyed. Dolomitization increased reservoir quality in grain dominated dolo-packstones with planner crystal texture.

Qezelbalaq Arsenic ore deposite is located in Hashtrud, 120 km from southeast of Tabriz. In this district effect of dacitic Sahand domes on sandy limestones and Qom formation sandstone with Oligomiocene age and pyroclacitic units with Miocene age leads to formation of various types of alteration such as Silicic, phyllic, intermediate argillic, advanced argillic and dolomitization. It seems that Arsenic mineralization has occurred in two main step: 1) Pyrite ± Chalcopyrite ± Arsenopyrite that are consistent with phyllic zone. Fluide responsible mineralization have high temperature (nearly 250 centigrade degree) and fs2 between 10-15 to 10-20 and 2) Pyrite ± Native arsenic ± Realgar ± Orpiment ± Galena ± Stibnite wich are consist with intermediate argillic and advanced argillic zones. Hydrothermal fluid in this stage has lower temperature (nearly between 180 to 210 centigrade degree) with fs2 between 10-7. 8 to 10-13. These assemblage are associated with hematite, diaspore, kaolinite, alunite and arsenolite. Average of arsenic grade in phylilc zone is 655 ppm and in argillic zone is 11930 ppm. Mass change calculation indicate enrichment in many metals such as As, Sb, Hg, Ag and Au. According to geochemical studies, As, Hg and Sb are pathfinder for probebly Porphyry copper mineralization and gold in study area.

We used 2D seismic profiles, field observation and well data to constrain the structural evolution of the Saveh basin during the late-lower Miocene to late Pliocene. During this period almost 8-9 kilometers of Upper Red Formation (URF) and the Pliocene conglomerates were deposited in the depocenter of the basin. During the late-lower Miocene (to early-middle Miocene? ), Syn-depositional activity of west-east-northwest-southeast trending high-angle fault zones, with an extensional component, created accommodation space for deposition of lower URF. Since the late-middle Miocene (or late Miocene), initiation of a compressional phase has resulted in regional deformation. The deposition of upper part of the URF and the Pliocene unit was contemporaneous with compressional deformation. During this stage, the middle part of the URF acted as an effective detachment horizon and detachment folds such as the Saveh and Taraz Naeen anticlines were formed. The thinning of the Pliocene conglomerates towards the crestal point of these folds indicates late structural growth. According to the top Qom depth map, there are no traps with fault independent closure within the Saveh basin. The top of the Qom Formation is estimated at-4250 m in the Taraz Naeen anticline.

The study area is a part of the Sanandaj-Sirjan zone which is mainly composed of metamorphic rocks, a variety of igneous basic rocks and sediments. the metamorphic rocks studied at west of Kheyrabad, North of Gol-e Gohar mine in Sirjan, Kerman Province are slate, phyllite, schist (garnet schist, amphibole schist, micaschist, kyanite schists), epidote amphibolite, amphibolite, gneiss, quartzite and marble. Amphibolite facies is the highest metamorphic grade in the region experienced by the rocks. Protolith of amphibolites is basic to intermediate igneous rocks with chemical composition of calc-alkaline. Based on Ti against V diagram and Nb-Zr-Ydiagram, amphibolites of the study area belong to mid-ocean ridges (MOR) and Volcanic arc tectonic environments in relation to Neotethys ocean. Mineral chemical features classify amphiboles as calcic amphiboles. average temperature of amphiboles is 630 C and maximum pressure is 7. 5 kbar for the studied amphibolites. Geothermal gradient of ~ 28 C/Km indicates a continental crust setting for metamorphism.

Economically the Surgah Formation is the most significant in the Zagros sedimentary basin. In this study, the calcareous nannofossils have been investigated of the Surgah Formation from the Shah-nakhjir section. The thickness of the Surgah Formation is about 147 meters and composed of marly limestone deposits with diversity and well-preservation of calcareous nannofossil assemblages. In total, 41species belong to 22 genera were determinate and ultimately have compared with nannofossil standard zones. According to identified nannofossils, the age of the Middle Cenomanian-Middle Santonian corresponding to CC10-CC17 (Sissingh, 1977) includes MicrorhabdulusdecoratusZone (CC10), Quadrumgartneri Zone (CC11), Lucianorhabdusmaleformis Zone (CC12), Marthasteritesfurcatus Zone (CC13), MiculadecussataZone (CC14), Reinhardtitesanthophorus Zone (CC15), Lucianorhabduscayeuxii Zone (CC16), Calculitesobscurus Zone (CC17) were suggested for the Surgah Formation in the studied section. Palaeoecological interpretations based on the identified species show warm climate and low depth conditions in low latitudes for deposits of the Surgah Formation in southwest of Ilam city (Shah-nakhjir section).

The determination of Petrophysical rock properties has always been an important part of geological modeling and also is used in reservoir engineering studies. Permeability (k) is one of the most important properties of porous media which is the measure of a porous material to allow fluids to pass through it. Permeability can be determined from both experimental tests and numerical simulations. Numerical simulations should be performed on geometries determined from advanced imaging techniques. Digital rock physics (DRP) is an approach for studying rocks nondestructively. In this paper, 10 carbonate rock plugs from the oil fields in South-West of Iran were imaged by medical CT scan and the outputs were used for image processing and permeability determination. We evaluated the use of Navier-Stokes equations to perform fluid flow simulation through the pore spaces geometry. The permeability of the samples were calculated and compared with laboratory-derived values. The results indicated a trend between the permeability values reported by the laboratory and medical CT images with R2=90%.

Among the sedimentary units of the east flysch basin in the Nosrat-Abad area, where in the 105km northwest of Zahedan, there is a sandstone-conglomerate unit with an Oligo-Miocene age. The depositional environment of this deposit was fluvial which has been morphologically dissected in several portions; this unit covers the Eocene sandstone-shale deposits by an angular unconformity about 30 degrees. The measured thickness is about 2650 meters. The composed particles and pebbles are in various grain size. On the other hand, sandstone, siltstone, and mudstone accompany the conglomerate unit. Field observations document the unit was formed in a fluvial depositional environment. Imbrication and cross, smooth, and lens-shaped bedding are the main recognizable sedimentary structures. Moreover, the caved and filled structure are seen. Note that there is difference between the lithology of the pebbles in the conglomerate and the rocks composing the flysch zone, the pebbles could be originated from the west side, where in the Lut block. The recognized fossils from limestone pebbles are belong to the families such as Orbitolina, Alveolina, Nummulite, and Miliolid, consequently, the age of conglomerate-sandstone unit must be younger than Eocene and cover by Conglomarate Quaternary probably could be Oilgo-Miocene.

Archaeologists believe that men who lived in Archaeological sites of Mazandaran such as Komishan cave, Hutu and Kamarband, After leaving the cave were gradually formed the Gohar tappeh. Over time, people living with the loss of previous places were higher places. In Neolithic village has been form of rural life there, and And the Bronze period considered and the state of urbanization has found. Archaeological studies dating this area back to seven thousand years and findings of the Bronze era (the third millennium), Iron II Age (mid-second millennium B. C. ) unfold it. this study provided Archaeoseismology based on knowledge paleoseismological on the fault system of the Khazar in the protohistory area on Gohar tappeh in Behshahr of Mazandaran province. Field reviews of paleoseismological has been in the archeology trenches of the Gohar tappeh site and geophysical data (GPR and geoelectric) from this range is evaluated at the appropriate scale. On the basis of paleoseismology researches, five earthquake events in period of 3500 to 5000 past years, with magnitude of 7-6. 2 on the moment magnitude scale (Mw) detected. The maximum displacement of detected index in paleoseismological observations by the Geophysical perceptions and GPR data also confirmed. Moreover the average course back of earthquake events is estimated at about 375 years. According to Archaeoseismology researches conducted in area, occurrence of earthquake events has been identified that in Range a few hundred years ago Cause loss or migration and immigration of protohistorical Gohar Tappeh people.

The Roshtkhar intrusive rocks are located in the northeastern part of the Roshtkhar prospecting area (KhorassanRazavi province), along the eastern edge of the Khaf-Kashmar-Bardaskan volcano-plutonic belt, north of the Dorouneh Fault and on the southern part of the Sabzevar structural zone. The intusive rocks consist mainly ofsyenite to monzonite with minor amount of syenite porphyry, monzonite porphyry, and diorite porphyry with granular and porphyry texture, respectively. According to the geochemical data, the Roshtkhar intrusive rocks are calc-alkaline granitoid series with high-K to shoshonitic affinity, magnesian, metaluminous, and belong to I-type granites. Chondrite-normalized Rare Earth Element and mantle-normalized trace-element spider diagrams display enriched in LILE and LREE and also Th, depleted in HFSE and weak depletion in HREE and Y, along with negative anomalies of Nb, Ta, and Ti, that are characteristic of the post-collisional calc-alkaline rocks along with a continental active margin tectonic setting. In spite of the low ratios of Nb/U, Nb/La and Ce/Pb, the Sm/Yb (2. 8-3. 9) ratios reveals low contamination of magmas with upper continental crust. According to geochemistry of trace elements and REE, the main cause of magmatism in Roshtkhar area was melting of a metasomatized lithospheric mantle (E-MORB) with spinel lherzolite composition accompanied by in the presence of phlogopite. Multiple element and REE pattern, abundance of K2O/Na2O in Roshtkhar intrusive rocks show contamination and mixing with acidic magma ofamphibolitic lower crust due to temperature of mantle magma and AFC process played important roles in magma evolution. La vs. La/sm diagram illustrate partial melting and also according to K, positive anomalies of Rb, Ba, K, Th, U, and Pb, and the negative anomalies of Nb, Ti, Ta, and Ba associated with high La (La > 29), it seems partial melting of lower continental crust has played an important role in the genesis of the Roshtkhargranitoids rocks. Based on field investigation, petrographic studies, and lithogeochemistry using the granitoids discrimination tectonic setting diagrams, it seems that the Roshtkhar intrusive rocks were generated in a post-collisional extensional environment in a continental margin arc setting with partial melting of the mantle-lower crust within the Khaf-Kashmar-Bardaskan belt.

The area of Duna mine is a part of central Alborz. The Duna anticline is a part of pop up structure and located between Kandavan and Azadkuh thrust faults. In this research three sets of major faults are recognized. The first category of faults with W-E trend, dip 40-50, Rake angle more than 70, are parallel to the major fold axes and second category of faults have NE-SW trend with reverse movement and rake angle less than 65. The third category which truncate the first sets, have nearly N30W to N40W direction with dip more than 75 and rake angle more than 70. The aim of this paper is investigation on the structure of Duna mine and investigations on the mechanism of third category of faults which are not popular in Alborz range and did not discussed before. Some of these faults do not have visible slickensides and the mechanism of these faults held on the basis of preparing geologic map on the scale of 1: 1000, structural cross sections and implementing Schmidt net with construction methods. The change of tectonic movements from collision into sinstral, on the pop-up structure created this set of young reverse faults with NW-SE trend.

On 1-12 December 2017 three earthquakes (Mw 5. 9-6. 1) shake Hojedk region in Kerman province. We used satellite images, radar interferometry and field investigation to examine the sourceprocesses of these earthquakes in south– central Iran. The epicenter of first two events located near northern boundary of the Miankuh, a major topographic feature of the region. No surface rupture has been seen with these events and InSAR results show semi symmetric uplift of the region. Therefore, two scenarios of faulting with dip to the SW or NE are possible. Epicenter of the third event located further north within the alluvial plane. Evidence for coseismic surface rupture associated with this event was first observed on Sentinel satellite image and InSAR analysis. It was then confirmed by field investigation. The event produced a coseismic scarps with more than 1 m vertical displacement over a total distance of∼ 6 km, along a fault with reverse mechanism and dip to the SW. Any signs of earlier coseismic ruptures along this fault had been obliterated by the time of the 2017 earthquake, probably by occasional flash floods, so that the fault could not been identified beforehand. However, there is evidence of young alluvial offsets further to the NW along strike of the fault, suggesting existence of active structures in the region. Reactivation of blind faults have caused other major earthquakes such as 1978 Mw 7. 4 Tabas, 2003 Mw 6. 6 Bam, and 2017 Mw 7. 3 Sarpol Zahab earthquakes in the past. The Hojedk earthquakes remind us about importance of recognizing and studying blind faults, especially if they are close to population centers.

In northeast of Sarbisheh, southern Khorasan, outcrops of lava rocks exist that from view of geological subdivisions, located in eastern part of Lut block. Petrographic composition of studied rocks include of andesite (pyroxene andesite, andesite, trachy andesite), dacite and rhyolite. The main textures of these rocks are porphyry with microlitic-glass groundmass, glomeroporphyritic, poikilitic and vesicular. The constituent minerals of andesites are plagioclase, pyroxene and amphibole with small amounts of biotite and sanidine, in rhyolite and dacite include of quartz, sanidine, plagioclase, amphibole and biotite. Disequilibrium textures such as chemical zoning, sieve texture, rounded and gulf shape margins observed in phenocrysts of these rocks. Geochemical studies results show that these lavas belong to high to medium-K calc alkaline series. Enrichment in LREE and LILE, depletion in HREE and HFSE with negative anomaly of Ti, Nb and P in these rocks suggests active continental margin volcanic arc magmatism. Based on tectonic discrimination diagrams, Zoolesk area lavas are related to subduction zone and active continental margin. Low ratio of Dy/Yb(<2) in studied lavas, represents a spinel lherzolite mantle source for magma.

In open pit mines, the extraction of ore rock with minimum price and good quality is the most important mining goal. Sarcheshmeh copper mine is not excluded from the existence of underground water, like other open-pit mines. In this paper, the impact of underground water on production costs and mining process has been investigated. For this purpose, the parameter specific crushing(S_cr ), measured and used. To evaluate mining operation in dry and wet conditions of database in two parts of production costs and mining operations of two blasts, holes with diameter of 6 inches were created. The difference of two different conditions of mining in increasing production costs and reducing production performance is observed such that the costs including drilling cost, blast cost, total drilling and blast costs, loading cost are increased respectively, equal to 83. 33, 450, 266. 67 and 200 percent in wet mining conditions compared with dry conditions. Rock crushing cost due to crushing amount is almost similar in both conditions. Also, wet mining conditions cause reducing the production yield of Sarcheshmeh copper mine such that production performance in sections including special loading and index specific mining operations unit has been decreased respectively, equal to 33. 34 and 198. 85 percent compared to dry conditions. In order not to use waterproof explosives, improvement of mining operations index and reduction of project production costs, it is necessary to determine the model of underground water of Sarcheshmeh copper mine. Desirable mining operation will be provided with lower cost with sustainable development by drainage of underground water in open pit mines.

Delfard area is located in the northwestern of Jiroft, formed the northwestern part of the Jabā lbā rez granitoid complex, in Uromiyeh-Dokhtar magmatic belt. The Jabā lbā rez granitoid complex has a wide range of rocks inclusive from diorite to alkali granite, which were formed by magmatic differentiation process over the several course of consecutive pulses. Last pulses are masses of porphyry that showed evidence of copper mineralization. One of these intrusive bodies is Delfard. Copper mineralization in Delfard area is more important than other parts of Jabā lbā rez. Consequently, in the area, three porphyry masses showing the evidence of porphyry copper mineralization. Chalcopyrite, Pyrite, Malachite, Azurite and Magnetite are indicative minerals. Alteration zones in Delfard area are silicic, potassic, arjelic, phyllic, and propylitic that can be correlated with Lovell and Gilbert model. According to studies, Delfard has high potential for exploration and drilling. The average copper content in the ore is about 1800 ppm. Petrogenesis review of the mafic rocks in Delfard area shows that these rocks originated from a richer source than NMORB. In addition, the rocks of Delfard area are Flux melting pointer that happened in the subduction of oceanic crust under the adjacent crust. In other words, the sequence of calc-alkaline rocks of Delfard area attributed to compressional tectonic regime that intrusived and erupted along the Uromiyeh-Dokhtar zone with development and high volume in the form of magmatic horizons. Finally, petrogenesis of studied granite series is similar to the calc-alkaline granitoids, which was originated from basaltic magma mantle metasomatised by fluids from the subducted slab. Based on zircon U-Pb geochronology, the age of Delfard granitoid is 15. 90± 1. 3 Ma. One can imagine that, magmatic differentiation process was completed in a short time and intrusive body was sequentially penetrated and placed in the earth's crust in a short time.

Accumulation of Shemshak group lithofacies have been started during Early-Cimmerian orogeny from middle of Late-Triassic and ended with Middle-Cimmerian discontinuity dating Millde-Jurrasic. So the mostly Siliciclastic and occasionally Marin lithostratigraphic unite has evidences of two major tectonic events as orogenic activity at lower and upper border of sequence. Therefor the lower contact of Shemshak group is composed of Middle-Triassic platform carbonates known as Elika formation which distinguished with Plaeokarsts including bauxit and laterit horizons and the upper contact with parallel unconformity with Delichay formation fossiliferous marls and carbonates of Bajocian stage (Middle Jurrasic). Results of deposition environment and facies studies have shown that the mentioned siliciclastic group (Shemshak) composed of three major facies, 22 subfacies and have been deposited in three different environments including Fluvial (Terrestrial), mid-tidal and shallow marine environments. The vertical changes of facies have declared that the sequence has formed due to erosion of Early-Cimmerian uplands and have experienced progess of shallow marine. The existing shallow marine sediments in the end of Shemshak group states that, in comparison with surrounding area, clastic sediments of end of Shemshak cycle, because of erosional cycles of Middle-Cimmerian orogeny, befor deposition of Delichay marine formation, have been eroded.