Tungsten (Cu-Au-Zn) deposits and occurrences in Iran can be divided into two separate categories based on their genesis, tectonic setting, mineral par agenesis and related processes inherent in their formation. The first category contains deposits, which are located in metamorphosed Late Triassic-Middle Jurassic volcano-sedimentary sequences, and their distribution is indicated by layering. These deposits are located in a specific stratigraphic position and are concentrated in contact of volcanic units with carbonate rocks. The geodynamic setting of this category probably is intracontinental rifting. The second category contains deposits located in metamorphosed sedimentary rocks of the Shemshak group and Jurassic granitoids. These deposits have vein-veinlet geometry and their formation is controlled by faults, fractures and shear zones. The geodynamic setting of this category probably is active continental margins. The mineral paragenesis of the first group generally contains scheelite and Cu-Fe-Zn sulfides, whereas the paragenesis of the second group is wolframite, scheelite, chalcopyrite, arsenopyrite, with gold and specifically bismuth.

Introduction: Located in the NE Iran, the early Tertiary volcanic sequences host a vast STRATABOUND Cu mineralization (manto type), which is likely to be significant economically (Samani, 2002). The Pirmardan copper deposit is located 130 km southwest of Shahrood and is classified as a manto type mineralization, hosted by altered andesite to trachyandesite, volcanic breccia and tuff. The host rock suffers from two kinds of local and regional hydrothermal alterations of sericitecarbonate, and propylitic, respectively. Sulfide minerals occur as disseminated vein and veinlet forms in the host rock. Manto mineralization type in the northeast and central Iran could be a new prospective for the copper deposits subsequence of the Cu porphyry deposits in Iran (Samani, 2002).....

Azna tungsten (copper) ore occurrence is located 2 km west of Azna, in Lorestan province. The region is placed in Sanandaj-Sirjan structural zone of Iran, at the complex deformation sub-zone. In this area, tungsten-copper mineralization occurs as stratiform-STRATABOUND in mylonitic meta-rhyolite and semi-pelitic country rock within upper Triassic volcano sedimentary sequence. The sequence consists of meta-rhyodacite, amphibolite (basic meta-volcanic), black schist, meta-rhyolite and pelitic schist with a predominance of volcanics over sediments. Ore mineral textures cover a wide variety from laminated, disseminated, choloform, bounded to open space filling. Mineralization occurs in several stages concentrated through regional (medium to high grade facies) metamorphism, folding and mylonitization of shear zone (ductile) and fractures of brittle deformation events. In this ore occurrence, metamorphism and deformations process had confused detection of proximal or distal mineralization. But base of comparison of Azna tungsten mineralization with both typical proximal on Felbertal and Austroalpine and distal on Broken Hill and Kleinarltal tungsten mineralizations has shown that they are more similar to the proximal mineral deposits.

Introduction The Yeilaq Samanloo area is located 19 km southwest of Meshginshahr and 22 km west of Sablan in the West Alborz-Azarbaijan structural zone. Cenozoic igneous-pyroclastic rocks cover more than 95% of the area. The Eocene units are mainly composed of volcanic rocks, including andesite, trachy-andesite to trachy-basalt, tuff and shale layers. A granitoid intrusive body (granodiorite, monzonite, quartz monzonite) with Upper Oligocene age intruded the Eocene volcanic rocks and produced chlorite and epidote alteration in them, especially in the contact zone. A number of silica veins containing pyrite and chalcopyrite cross-cut both the granodiorite body and Eocene volcanic rocks, which host gold and copper mineralization. The youngest unit includes Sablan lavas of trachy-andesite, basaltic andesite and andesite with Quaternary age, which have flowed unconformably on the Eocene volcanic rocks.   Materials and Methods In this research, 65 samples were taken from stream sediments for geochemical studies. In order to check the anomalies revealed from stream sediment studies, 30 rock samples were taken for lithogeochemical studies and 10 petrological samples from the igneous rocks and were analyzed by XRF and ICP-MS (petrological samples), ICP-OES (geochemical samples of stream sediments) and Fire Assay (for gold) at  Zarazma lab.   Results and Discussion Based on the petrological diagrams, the volcanic rocks of the region mainly have andesitic to andesi-basaltic composition, high potassium calc-alkaline and shoshonitic nature, and meta-aluminous to per-aluminous affinity. The tectonic setting of these rocks is an active continental margin, and their trace and RE elements pattern is similar to the subduction-related rocks. Remote sensing and field studies show that the distribution of various alteration zones is not extensive. The chlorite-epidote (propylitic) alteration zone is the most widespread zone, mainly observed in the northeast and southeast of the area. Argillic and sericitic alterations are present in the central and southwestern parts, and the distribution of alunite-pyrophyllite alteration is scattered and very limited. Stream-sediment geochemical studies and lithogeochemical investigations upstream the observed anomalies led to the introduction of several Cu-Ag and precious and base metal mineralization areas for the first time in this region. Coincidence of geochemical anomalies with alteration zones shows that Cu anomalies are mostly associated with argillic and sericitic. The association of Au with argillic and sericitic alteration zones in the south of the area is noteworthy. But Ag mineralization is associated only with propylitic and to some extent, argillic alteration. Microscopic studies of rock samples showed that the Cu-Ag mineralization in the Samanloo area is STRATABOUND, being associated with andesitic units of the Upper Eocene and includes pyrite, chalcopyrite, bornite, malachite, azurite, chalcocite, native copper and to a lesser extent, covellite, which occur as disseminations, open space fillings and replacements, especially within the mega-porphyritic andesite unit. In the rock samples of this area, the highest anomalies of elements are: Cu (67800 ppm), Ag (18 ppm) and Au (1088 ppb). Based on the obtained statistical correlations, the anomalous elements were divided into three groups: (1) Cu-Ag, (2) As-Sb-S-Au and (3) Pb-Zn-Fe, which are attributed to three genetic-lithologic groups. The first group is related to the granitoid body, especially the halo around it. The second group is directly related to pyroclastic units and Eocene lavas, especially mega-porphyritic andesites and chlorite-argillic alteration zone within it. The third group can be attributed to the silicic veins/veinlets of the Neogene tectono-magmatic activities and the infiltration of hydrothermal fluids into fractures; Au displays more considerable anomaly among the elements of this group.   Conclusion Based on the characteristics of mineralization, including host rocks, STRATABOUND nature, mineralogy, metal content and alteration, it can be concluded that the mineralization at Yeilagh Samanloo area is of Manto-type copper deposits. According to the structure, texture and mineralogy of the mega-porphyritic andesite unit, two phases can be considered for the hypogene mineralization at the Samanloo area: primary diagenetic stage and burial stage. Early diagenetic processes led to the formation of pyrite within the porphyritic andesite unit, which is the host of mineralization, and as a result, reducing conditions have appeared in this unit. In the next stage, under the influence of the burial process, oxidant saline fluids have migrated and washed Cu from the underlying Cu-rich volcanic units (trachy-andesite, tuff with shale layers) and deposited it in the reducing mega-porphyritic andesites.

Bovaki and Aghbolagh tungsten (copper-tin-zinc) ore occurrences are located 12 and 14 km northwest of Azna respectively. The region is located in Sanandaj- Sirjan structural zone of Iran, at the complex deformation sub-zone. There are alternative comsisty Upper Triassic carbonate, quartzite and meta-volcanic rocks (such as meta-tuff). In this area, tungsten-copper mineralization occurs as stratiform- STRATABOUND in metamorphosed cherty, sandy, dolomitic limestone country rocks. In this sequence, the volumetric ratio of sedimentary rocks is more than that of volcanic rocks. Mineral paragenesis in the both areas consists of pyrite, scheelite, maghemite, lepidocrocite, Fe-oxide and hydroxide and occasionally chalcopyrite, chalcocite and malachite. Mineralization types are primary, diagenetic and STRATABOUND veinlet. Ore textures are disseminated, lenticular, replacement and open space filling. Mineralization contaben place by diaganetic processes and regional (low grade facies) metamorphism events. Comparison of Bovaki and Aghbolagh mineralization with both typical proximal and distal mineralizations has shown that they are more similar to the distal mineral deposits.

Similar to other deposits of this type in the world, three major stages could be considered for mineralization in Mari copper deposit. The Mari Copper deposit is located in the northwest of Iran and Tarom metallogenic zone in the north of Zanjan. The ore-body is strata-bound and hosted by the Eocene mega-porphyritic andesites. The major copper sulfides are bornite, chalcocite, and chalcopyrite associated mainly with pyrite that represent open-space filling, disseminated, vein-veinlet, and replacement textures. The volcanic rocks of the study area mostly represent intermediate to acidic composition with high potassium shoshonitic magmatic series related to intra-arc rift environments. Wall rock alterations include carbonatization, chloritization, epidotization, and sericitization. The abundances of Cu and Ag in fresh mega-porphyritic andesite are up to 3200 and 216 ppm respectively. Based on the main characteristics of Mari ore body such as tectonic setting, host rock, strata-bound form, mineralogy, metal content, and wall rock alterations and comparison of these features with Manto - type copper deposits, Mari Cu deposit can be introduced as a Manto -type Cu deposit in NW Iran. The first stage includes submarine volcanic activity and eruption of mega-porphyritic andesitic lava associated with regional propylitic alteration. In the second stage, the early diagenesis and the activity of sulfate-reducing micro-organisms resulted in the generation of pyrite in the form of open-space filling and disseminated in the mega-porphyritic andesite. Finally, in the third stage, increasing of the thickness of sediments, basin subsidence, and burial diagenesis accompanied with the entry of metal-rich fluids into the reduced host rock, caused the replacement of the first stage pyrites by copper sulfides and mineralization in the Mari deposit.

Daveh Yataqi Cu deposit is located ~72 km northwest of Abhar and is part of the Tarom-Hashtjin metallogenic belt. Mineralization occurs as a STRATABOUND zone hosted by the Eocene tuff units. The ore zone has an E-W trend with 60-70˚ to the north and is 200 m in length and 0.5 to 3 m in width. Hydrothermal alteration includes silica, chlorite, carbonate, epidote, and zeolite alteration. Supergene argillic alteration covered the margins of the ore zone. Hypogene chalcocite, bornite, chalcopyrite, pyrite, and native Cu are ore minerals; chlorite, quartz, calcite, epidote, zeolite, and clay minerals are gangue minerals. Supergene chalcocite, covellite, malachite, cuprite, and goethite are supergene minerals. The ore minerals show disseminated, vein-veinlet, vug infill, replacement, exsolution, framboidal, brecciated, relict, and colloform textures. Mineralization at Daveh Yataqi can be divided into four stages. Stage 1 is related to the early diagenesis processes in which disseminated framboidal pyrites are formed within tuff units. Stage 2 is related to the late diagenesis and burial metamorphism processes and is characterized by bornite, and hypogene chalcocite along with minor chalcopyrite with disseminated, vein-veinlets, exsolution, vug infill, and replacement textures. Stage 3 is marked by late quartz-chalcopyrite-pyrite, quartz-chlorite, and calcite vein-veinlets. Stage 4 mineralization is related to supergene processes. Characteristics of the Daveh Yataqi Cu deposit are comparable with the Manto-type deposits.

Introduction The sulphide deposits of STRATABOUND and stratiform are one of the largest sulphide deposits for copper mineralization. by examining and comparing the deposits and mineral signment discovered in the Eocene volcanics with Mantle type deposits in Chile, they concluded that the Manto deposits were formed in the uppermost porphyry andesitic lavas of Eocene Iran and can be considered as a metallogenic unit to explore this type of mineralization. In Iran, Manto type deposits have been reported just in Urumieh-Dokhtar zone, Sanandaj-Sirjan zone and Sabzevar sub-zone. Abari and Rahbari deposits are among the Manto type deposits in the volcanic-intrusive belt, Khaf-Darooneh and the southern part Sabzevar sub-zone. In this research, mineralogy, geochemistry and formation pattern of Abari and Rahbari copper deposit were discussed and investigated. Materials and methods In this research, 100 thin and polished sections were prepared and studied, and the studies of fluids inclusion were done by preparing and studying 3 double-polished sections from surface samples. In order to identify minerals and complete alteration studies, 6 samples were analyzed by XRD method and for geochemical studies, 22 samples of ore and volcanic-sedimentary rocks were analyzed by XRF and ICP-MS methods in Binalud deposits Laboratory and Iran mineral processing Research Center. Results and discussion According to the diagenetic-epigenetic model, the stages of mineralization and formation processes can be described in three stages: the first stage: initial diagenesis, the second stage: the burial diagenesis stage, and the third stage: the uplift stage (hydrothermal activities). Initial diagenesis stage: after extensive volcanic activities, during the diagenesis stage, in this stage, seawater sulfate regenerating bacteria were present in the environment, and their activity has caused regeneration conditions in the basin. As a result, the resulting sulfur with the available iron causes the deposition of pyrite in the form of scattered grains and fills the empty spaces in the rock background. Secondary diagenesis stage: from the stage of diagenesis onwards, burial occurs as a result of the deposition of newer sediments on them. the hydrothermal fluid carries the copper released from the conversion of iron hydroxide minerals into iron oxides, as well as the copper released in the network of feldspar minerals in the transformed volcanic units due to the high environment temperature and circulation in the volcanic and pyroclastic units and then turning up in the rock units, it reached the pyroclastic unit with high porosity and permeability, and chalcocite and chalcopyrite minerals were formed in the burial diagenesis stage. upwelling Stage (hydrothermal activities): at the end of the burial process and with the beginning of the uplift of the area and faulting, the open spaces increase by Darooneh and Binalood faults, which ultimately causes the activity and concentration of sulfide and copper oxide mineralization will start again along the faults, cracks, and even the empty spaces of the pyroclastic units. Conclusion The Eocene volcanic rocks of the magmatic belt in the north of the structural zone of central Iran are the host of Abari and Rahbari copper deposits with the dominant composition of andesite and basaltic andesite. The effective factors copper mineralization in the study areas including: 1) The lithology of host rocks, 2) structural controls, 3) hydrothermal fluids and 4) The presence of intrusive rocks at depth and basaltic dykes. The controllers play a significant role in the transfer of hydrothermal fluids and their accumulation and deposition. Mineralization is formed in three stages: initial diagenesis, burial diagenesis and uplift stage (hydrothermal activities). The dispersed pyrites is source of sulfur in reducing conditions (resulting from the activity of seawater sulfate reducing bacteria). Based on the studies of intermediate fluid loads, the processes of dilution with surface fluids, mixing with isothermal fluid, cooling and pressure reduction can be considered responsible for the changes created in the fluid. So that mineralization in the Abri and Rahbari area is epigenetic, strata bound that is similar to the manto type copper deposits.

The Vehnoveh area situated about 60km south of Qom in Orumieh-Dokhtar volcanic zone. Most of rocks of this area are middle and upper Eocene. Volcanic rocks combination consists of Basaltic andesite, Andesitic basalt, Olivin basalt, Olivine dolerite, Crystal lithic tuff and Andesite megaporphyr. Delayed magmatism accompanied with the Eocene volcanic phase has caused a series of lava flows and a lot of dikes in this area. These dikes and flows have a combination of Andesite to differented Andesites towards the Albitite pole and contain gabbroic enclaves. In this area, traces of copper mineralization and ancient mines works are seen. The main copper minerals are Malachite, Chalcosite and Covellite. Mineralization is limited to a bedded horization of Basaltic andesite lava with Amigdaloidal texture; therefore, it is considered as a mineralization of stratabund type. The Most of mineralization textures are veins and veintels type and filler of vesicles. The consideration placed of in to the Epithermal class and it can be compared with the Michigan type.

Miandasht copper deposit is located in 110 km east of Shahrood, 24km north west of Abbasabad, and in the Cenozoic volcanic belt of north of Central Iran zone. The major rock units of the study area have Eocene age and include submarine flows (andesite, basalt, and trachyandesit), pyroclastic (tuff breccia and agglomerate) and sedimentary complex (Nomullitic limestone, tuffacous limestone, shale, sandstone and conglomerate). Mineralization in the Miandasht copper deposit occurred as parallel to layering of the host rocks (tuff breccia and agglomerate), and also along with cross-cutting faults of the host rocks in form of STRATABOUND and epigenetic ores. The main ore textures include vein-veinlets, open space filling, disseminated and replacement. The Ores contain primary pyrite, chalcopyrite, chalcocite, bornit, and secondary covellite, chalcocite, malachite, hematite and limonite. The most important wall rock alterations accompanied with mineralization are carbonatic-silicic, sericitic, argillic, and chloritic, and that the amound of carbonatization and silicification increases with closing to mineralization zones. According to geochemical studies, tectonic setting of the deposit was extensional environment formed in a continental margin volcanic arc. Based on essential characteristics of the copper mineralization such as tectonic setting, host rocks, mineralogy, and type of alterations, the Miandasht copper deposit shows many similarities with Manto-type deposits, dominantly formed during orogeny, folding and faulting of the host sequence. It should be mentiond that some charachteristic features of the Miandasht copper deposit including development of argillic alteration, and lack of extensive zeolitic alteration, distinguishes it from other copper deposits in the region including Abbasabad deposit.