Editor-in-Chief Lecture
Volume 29, Issue 113 , November 2019, Pages 1-1
Reviewers
Volume 29, Issue 113 , November 2019, Pages 2-2
Original Research Paper
Petrology
Seyyed Navid Seyyed Mardani; M. Moazzen; Ahmad Jahangiri
Abstract
The Muth-Golpayegan metamorphic complex is situated at north of Golpayegan city in the Isfahan province. This complex is constituted from different metamorphic rocks including variety of pelitic schists, amphibolite, gneiss, quartzite and marble. Garnet schists are dominant lithology in the area and ...
Read More
The Muth-Golpayegan metamorphic complex is situated at north of Golpayegan city in the Isfahan province. This complex is constituted from different metamorphic rocks including variety of pelitic schists, amphibolite, gneiss, quartzite and marble. Garnet schists are dominant lithology in the area and contain different minerals, such as garnet, quartz, chlorite, muscovite, biotite, staurolite, andalusite, kyanite and sillimanite. Lepidoblastic, porphyroblastic, poikiloblastic, augen and millipede are the main textures in these rocks. The degree of metamorphism increases from SW to NE in a way that slate and phyllite at SW change gradually to chlorite schist, biotite schist, garnet schist, staurolite schist, sillimanite schist and kyanite schist. The occurrence of these schists is accompanied by appearance of chlorite, biotite, garnet, staurolite, sillimanite and kyanite mineralogical zones in the field. The succession of these zones is compatible with Barrovian regional metamorphic gradient. Chlorite, biotite and garnet zones belong to the greenschist facies and staurolite, sillimanite and kyanite zones belong to the amphibolite facies. Temperature range calculated for these rocks by garnet-biotite thermometry is 471-581 C. This metamorphic gradient is a result of continental collision.
Original Research Paper
Geophysics
Mohammadreza Jamalreyhani; Abdolreza Ghods; Seyyed Khalil Mottaghi; Esmail Shabanian; Morteza Talebian; Beijing Chen
Abstract
One of the main issues in Zagros is the extent that basement and the thick sedimentary layer participate in the observed seismicity. During Nov. 2013, five magnitude ~5 Mw events hit a region in the western end of Lurestan arc of Simply Folded Belt (SFB) of Zagros. We used the Iran-China temporary network ...
Read More
One of the main issues in Zagros is the extent that basement and the thick sedimentary layer participate in the observed seismicity. During Nov. 2013, five magnitude ~5 Mw events hit a region in the western end of Lurestan arc of Simply Folded Belt (SFB) of Zagros. We used the Iran-China temporary network and data from regional permanent networks to relocate the events using a multiple event relocation method, calculate regional moment tensor and centeriod depths for the five moderate events and estimate a velocity model for the two nearby seismic stations using joint inversion of the receiver functions and dispersion curves. Our results show a seismic cluster of about 30 km long and 15 km width. The moment tensor solutions of the five moderate events indicate an almost pure thrust mechanism. The aftershock cloud indicate a low angle east dipping fault plane (i.e., , dip in the range of 23 o -39 o ) as the causative fault plane. The calculated centeroid of the five moderate events are about 14 km and the focal depth of all events calculated by multiple event relocation are about 10-16 km. The results indicate that the thickness of sedimentary column is less than 8 km and thus showing the whole seismic cluster happened within the basement. This observation proves wrong the hypothesis of vertical separation of mainshock and aftershocks in Ssimply folded belt FB of Zagros (Nissen et al. 2011) and implies that in the Lurestan arc the sedimentary layers are deformed aseismically.
Original Research Paper
Stratigraphy and Palaeontology
A. Mahanipour; Reza Afrooz
Abstract
In the present study, calcareous nannofossil biostratigraphy was investigated at the Paleocene ‒ middle Eocene interval at northeast Kazerun (Shahneshin anticline). A thickness of 50 m from the upper part of Gurpi ‒ lower part of Pabdeh formations is investigated and mainly consists of marly limestone, ...
Read More
In the present study, calcareous nannofossil biostratigraphy was investigated at the Paleocene ‒ middle Eocene interval at northeast Kazerun (Shahneshin anticline). A thickness of 50 m from the upper part of Gurpi ‒ lower part of Pabdeh formations is investigated and mainly consists of marly limestone, marly shale and marl. 180 species from 31 geneus of calcareous nannofossils are identified. According to the index calcareous nannofossils and based on Agnini et al. zonation, zone CNP3 to CNP11 and zone CNE1 to CNE8 are identified at the Paleocene and Eocene interval, respectively. These biozones corresponds with zone NP3 to NP9 (in Paleocene) and NP10 to NP14 (in Eocene), based on Martini zonation. Regarding calcareous nannofossil assemblages and biozones, the Paleocene ‒ Eocene boundary is located between CNP11/NP9 and CNE1/NP10 zones, where the top of Fasciculithus richardii group is recorded. The extinction of Fasciculithus is recorded at 23 m by the last occurrence of Fasciculithus tympaniformis, which is considered as an index for early Eocene. The appearance of some species, such as Rhomboaster spp., Tribrachiatus bramlettei and assymetrical species of Discoaster araneus is recorded at the Paleocene ‒ Eocene boundary similar to other parts of the world.
Original Research Paper
Hydrology
babak najafiha; vlademer V.R.Boynagryan,
Abstract
The Caspian Sea is the greatest Lake in the world. It witness substantial fluctuation during the geological time. The study area located in Mazandran Province at south east of Caspian Sea. In this study effects of sea level fluctuation on south east of Caspian sea (Miankhaleh spit and ...
Read More
The Caspian Sea is the greatest Lake in the world. It witness substantial fluctuation during the geological time. The study area located in Mazandran Province at south east of Caspian Sea. In this study effects of sea level fluctuation on south east of Caspian sea (Miankhaleh spit and Gorgan Bay) has been studied in detail. The present research is a combination of field investigation, together with photometry , study of aerial photos and satellite image interpretations belong to a period of 40 years. The effect of the sea water fluctuation from 1975 to 2014 on the size of Gorgan Bay, sandy Miankhaleh split, along with construction of protective walls, breakwaters, inundation of agriculture land, roads and land use change have been discussed and investigated.
Original Research Paper
Remote Sensing
Seyedeh Sakineh Mousavi; Mehdi Honarmand; Hadi Shahriari; Mahdiye hosseinjanizadeh
Abstract
Mineral exploration in Esfandagheh area, located in south east of Kerman province is complicated due to verity of metallic deposits including volcanogenic massive sulfide copper, skarn iron, and volcanic manganese. This research was carried out with the aim of defining a model for mineral exploration ...
Read More
Mineral exploration in Esfandagheh area, located in south east of Kerman province is complicated due to verity of metallic deposits including volcanogenic massive sulfide copper, skarn iron, and volcanic manganese. This research was carried out with the aim of defining a model for mineral exploration and providing mineral potential map using remote sensing data. ASTER and OLI images along with various image processing techniques including color composite of band ratios, principal component analysis (PCA), and QI and SI indices were applied to recognize the hydrothermal alteration halos. Result validation was done through field and laboratory studies. Argillic, phyllic, propylitic, and iron oxides/hydroxides alterations were enhanced using color composite ratios of ASTER bands like (B4+B7)/B6 in red, (B4+B6)/B5 in green, and (B7+B9)/B8 in blue. Hydrothermal alteration mapping was also accomplished using selected PCA of OLI 2, 4, 6, and 7 bands, ASTER 4 to 9 bands and a combination of OLI 2 and 4 bands along with ASTER 4 to 9 bands. ASTER thermal infrared bands applied to determine QI and SI indices for enhancing silicic halos. Mineral potential map was produced through integrating alteration maps by fuzzy logic method in which seven areas were identified such as Sargaz Kuh copper mine, Hossein Abad manganese mine, and Esfandagheh iron mine. Results showed the possibility of establishing mineral exploration model and producing mineral potential map in reconnaissance and prospecting stages using appropriate sensors and image processing techniques.
Original Research Paper
Petroleum geology
Seyed Mahmoud Fatemi Aghda; Mashaallah Taslimi; Ahmad Fahimifar
Abstract
The main aim of this study is to examine the feasibility of estimation of flow zone indicator in carbonate rocks by integration of hydraulic flow unit concept a nuclear magnetic resonance technology. The two main permeability models Timur-Cotes and mean T2 models, because of worldwide usage of these ...
Read More
The main aim of this study is to examine the feasibility of estimation of flow zone indicator in carbonate rocks by integration of hydraulic flow unit concept a nuclear magnetic resonance technology. The two main permeability models Timur-Cotes and mean T2 models, because of worldwide usage of these models, were used for evaluating the ability of nuclear magnetic resonance to estimate the flow zone indicator. One of the most important points in this study is the use of the experimental results of the nuclear magnetic resonance in laboratory on core that is never done in Iran. In this study, 24 carbonate samples were selected, and porosity, permeability and nuclear magnetic resonance experiments were performed. Then, using the results of the porosity and permeability tests, the flow zone indicator was determined and was considered as an index for evaluating the accuracy of the nuclear magnetic resonance method. Using the parameters obtained from the nuclear magnetic resonance test and nuclear magnetic resonance permeability models, flow zone indicator was estimated and compared with the core flow zone indicator. According to the results, it seems that the nuclear magnetic resonance permeability models, with the routine coefficients, do not have the proper ability to estimate the flow zone indicator, and it is necessary to correct the coefficients according to the lithology of rocks.
Original Research Paper
Stratigraphy and Palaeontology
mahdi badpa; Hamed Yarahmadzahi; Kaveh Khaksar
Abstract
The Anarak Group with Zaladu (Gzhelian-Asselian age) and Tigh-e-Madanu (Sakmarian age) formations in the Ozbak Kuh Mountains (Central Iran) is more than 180 m thick and includes thick units of conglomerate, shale, sandstone, calcareous sandstone, sandy limestone, fusulinid limistone, marl and dolomite ...
Read More
The Anarak Group with Zaladu (Gzhelian-Asselian age) and Tigh-e-Madanu (Sakmarian age) formations in the Ozbak Kuh Mountains (Central Iran) is more than 180 m thick and includes thick units of conglomerate, shale, sandstone, calcareous sandstone, sandy limestone, fusulinid limistone, marl and dolomite layers. In the sequence of Zaladu formation, the accumulation of coral species of Pseudozaphrentoides winsnesi Flügel, 1995, was abundantly identified in two horizons in the upper part of the Ghezelin layers. Based on fuanal composition, diversity and abundance, spacing of corallits and microfacies, the mentioned accumulation is categorized as low-level (of Type A, ecological zone of A2). This zone represents a tough ecological condition where only a limited number of solitary corals could have survived the life-threatening factors. Based on microfacies studies, the coral community was identified to be restricted to the shoal and around it (lagoon toward shoal and open sea toward shoal) in a shallow platform.
Original Research Paper
Economic Geology
nader taghipour; Tahereh Rabani; Reza Zahiri
Abstract
Coal deposits in Gheshlagh region are embedded in the sediments of Shemshak formation with lithological units such as sandstone, conglomerate, siltstone, limestone and argillite. For investigation of mineralogy and structural characteristics of Gheshlagh coal seams sampled of eleven coal seams in four ...
Read More
Coal deposits in Gheshlagh region are embedded in the sediments of Shemshak formation with lithological units such as sandstone, conglomerate, siltstone, limestone and argillite. For investigation of mineralogy and structural characteristics of Gheshlagh coal seams sampled of eleven coal seams in four active mines. Occurrence of minerals with distribution and nature of organic – mineral bonds in coals seams of this region is considered by using of petrographic and XRD and FT-IR analyses. Study of hand specimen and polished section are approved the presence of clay minerals, pyrite, chalcopyrite, siderite and quartz. Also The presence of minerals like kaolinite, quartz, siderite, dolomite, calcite, pyrite, montmorillonite and biotite was revealed by XRD. Mineral–organic bands such as: OH, CO2, CH3, Si-O, S-S, C-S, Al-OH, carbonate minerals, C=C, aromatic and aliphatic CH have been identified by the FT-IR in Gheshlagh coal seams. Raman spectroscopic confirms the presence of the graphitic band (G) (1581 cm−1- 1585 cm−1) and the defect band (D1) (1341 cm−1 – 1352 cm−1) in Gheshlagh coal seams. Graphitic bands contain high intensity and insignificant broadening.
Original Research Paper
Petrology
Siavash Omidianfar; mohammad rahgoshay; Iman Monsef
Abstract
Koudakan Granitoid located in 100 km South of Birjand and 18 km North of Ghaleh-Zari mine in eastern Iran. It belong to the Lut Block volcanic–plutonic belt. These intrusive rocks (Eocene-Oligocene) petrogaphicaly composed of Diorite, Monzodiorite, Quartzmonzodiorite, Tonalite, Porphyritic Tonalite, ...
Read More
Koudakan Granitoid located in 100 km South of Birjand and 18 km North of Ghaleh-Zari mine in eastern Iran. It belong to the Lut Block volcanic–plutonic belt. These intrusive rocks (Eocene-Oligocene) petrogaphicaly composed of Diorite, Monzodiorite, Quartzmonzodiorite, Tonalite, Porphyritic Tonalite, Granodiorite, Granite and Porphyritic Granite. Plutonic rocks in this area have features typical of high-K calc-alkaline to shoshonite series, metaluminous and belong to I-type Granitoides. Enrichment in LILE rather than HFSE (RbN/YN: 38.12-124.93), negative anomalies of Nb and Ti and enrichment in LREE rather than HREE (LaN/YbN: 6.74-12.03) in all of samples are important evidences for the formation of this rocks in a subduction related magmatic belt. Positive anomalies of Pb and K indicate the involvement of continental crust in evolution of parental magma. Parallel trend of the samples in spider diagrams show that they are co-genetic. Elements ratios and Different discrimination diagrams show the formation of this rocks in an active continental margin with about less than 45 Km crustal thickness in per-collision steps. Parental magma has been generated by low degree partial melting (less than 5%) of an enriched peridotite in mantle wedge (Spinel lherzolite.).
Original Research Paper
Sedimentology
Saeideh Rahmani; Behrouz Rafiei
Abstract
The Oligo-Miocene Asmari Formation consists of carbonate facies with lesser amount of evaporites. The evaporite unit deposited at the base of the Asmari Formation is called Basal Anhydrite. Depositional model was investigated using field data, geophysical logs and the Basal Anhydrite facies ...
Read More
The Oligo-Miocene Asmari Formation consists of carbonate facies with lesser amount of evaporites. The evaporite unit deposited at the base of the Asmari Formation is called Basal Anhydrite. Depositional model was investigated using field data, geophysical logs and the Basal Anhydrite facies in the Dezful Embayment (DE). Seven microfacies were recognized in seven outcrops located in the Bangestan, Sefid, Asmari and Anaran anticlines. They were deposited in tidal flat and lagoon environments of inner ramp. Anhydrite facies is a distinct and pure evaporite unit with no carbonate components. Two main textures, fine crystalline (alabastrine) and coarse crystalline (porphyroblast), were distinguished in samples indicating replacement of anhydrite by gypsum. Gamma ray, neutron, sonic and density logs of 20 wells in 15 oilfields in the DE indicate that evaporite facies, present at the base of the Asmari Formation, is composed of anhydrite and halite. Anhydrite is present in the most of the DE wells and halite and small amount of anhydrite are present in three central wells. The results of geophysical logs and microfacies studies of the Asmari Formation reveal shallow water-shallow basin environment for the Basal Anhydrite.
Original Research Paper
Exploration and Mining
Maliheh Abbaszadeh; Ardeshir Hezarkhani; Saeed Soltani-Mohammadi
Abstract
In recent years, economic geology studies have become very popular method in mineral exploration studies. Modeling fluid inclusion data is one of the common studies in economic geology. In this research artificial neural networks method, as one of the machine learning algorithms, is used for three-dimensional ...
Read More
In recent years, economic geology studies have become very popular method in mineral exploration studies. Modeling fluid inclusion data is one of the common studies in economic geology. In this research artificial neural networks method, as one of the machine learning algorithms, is used for three-dimensional modeling and application of the results of fluid inclusion analysis in Sungun porphyry copper deposit. For this purpose, fluid inclusion data is used for directly separation of related alteration zones with mineralization (Potassic, Phyllic and Potassic- Phyllic). Due to the relation that exists between alteration zones and mineralization areas, based on 173 fluid inclusion data the separation of alteration zones is modeled by artificial neural networks method in Sungun porphyry copper deposit. According to the validation studies, it can be concluded that precision of this model is appropriate (83%) and trained model could be used for separation of alteration zones in Sungun porphyry copper deposit.
Original Research Paper
Exploration and Mining
Saeid Ghasemzadeh; Abbas Maghsoudi; Mahyar Yousefi
Abstract
The Baft district in Kerman province is located in the southeastern segment of the Urumieh-Dokhtar magmatic arc. This arc is characterized by thick accumulations of Cenozoic plutonic and volcanic rocks and provide favorable conditions to the development of hydrothermal systems and mineral deposition, ...
Read More
The Baft district in Kerman province is located in the southeastern segment of the Urumieh-Dokhtar magmatic arc. This arc is characterized by thick accumulations of Cenozoic plutonic and volcanic rocks and provide favorable conditions to the development of hydrothermal systems and mineral deposition, in particular porphyry copper mineralization. For mineral prospectivity mapping (MPM) to delineate prospective areas some individual maps of evidence including distance to intrusive contacts, fault density, distance to hydrothermal alterations and multi-element geochemical signature were generated. Spatial evidence values in each map were transformed using a logistic function of unbounded values into the [0,1] range. Thus continuous maps of fuzzy evidence layers were integrated using geometric average function. To evaluate results of final potential map a data-driven prediction-area was used. The results showed that for the geometric average prospectivity model, 87% of the known mineral occurrences are predicted in 13% of the study area. Hence, this method can be utilized for mineral prospectivity mapping to delineate target areas for further exploration of a certain deposit-type.
Original Research Paper
Economic Geology
shahriar keshtgar; Sasan Bagheri; shahriar keshtgar
Abstract
Abstract The Mahirud volcano-plutonic Complex (MVPC), known as Cheshmeh Ostad Group, an rock assemblage including several plutons and volcano-sedimentary successions, crops out at the northeastern part of the Sistan Suture Zone. Igneous rocks of the MVPC, consist of volcanic lavas and pyrclastic rocks, ...
Read More
Abstract The Mahirud volcano-plutonic Complex (MVPC), known as Cheshmeh Ostad Group, an rock assemblage including several plutons and volcano-sedimentary successions, crops out at the northeastern part of the Sistan Suture Zone. Igneous rocks of the MVPC, consist of volcanic lavas and pyrclastic rocks, are andesitic basalt, diabase, microgabbro and dacite that were intruded by the late cretaceous granitoids. The volcanic rocks have characteristics of the calc-alkaline to tholeiitic magmatic series. The spider patterns normalized to N-MORB and Chondrite is similar to the ones belong to the supra-subduction zone (SSZ) and Islanc arcs ( IAT). The EPMA studies on the key minerals in volcanic rocks such as clinopyroxene , brought the same results. The pribable presence of an island-arc chain in the Sistan Suture Zone, which some of its parts are considered here as the MVPC, is comparable to continuation of the pakistanian Chagai-Raskoh and Kuhistan Cretaceous-Eocene island-arc/s in east. Considering this reality, we must expect to have a larger ocean much wider than what was already proposed for the Sistan Ocean as a narrow oceanic seaway in Continental rifting setting.
Original Research Paper
Economic Geology
Zahra Kaboodi; Majid Ghaderi; Ebrahim Rastad
Abstract
The Kahak copper deposit occurs in the Eocene volcano-sedimentary sequence of Qom region, Urumieh-Dokhtar magmatic arc. The oldest rock unit in this sequence is a crystal tuff, overlain by tuff, andesite, sandstone, conglomerate, and limestone. Host rocks to the Kahak deposit include andesite and tuff, ...
Read More
The Kahak copper deposit occurs in the Eocene volcano-sedimentary sequence of Qom region, Urumieh-Dokhtar magmatic arc. The oldest rock unit in this sequence is a crystal tuff, overlain by tuff, andesite, sandstone, conglomerate, and limestone. Host rocks to the Kahak deposit include andesite and tuff, and the geometry of mineralization is stratabound. Mineralographical studies show that the ore minerals are pyrite, chalcopyrite, chalcocite, native copper, bornite, galena, covellite, digenite, and malachite accompanied by magnetite, and hematite. Based on mineralogical studies, two types of alteration are recognized in the volcanic rocks of the area, general alteration, and ore mineral alteration. The propylitic alteration is an indication of general alteration. The main alteration types in the mineralized zone of the deposit include carbonatization, silicification, chloritization, epidotization, and zeolitic. Dissemination, open space filling, vein-veinlet, pseudo-lamination, and replacement are the major textures and structures of the ore minerals at Kahak. Two major stages are distinguished for mineralization at the Kahak deposit. The first stage is volcanism and pyrite formation in the host rocks (andesite and tuff), producing reduction state. The second stage involves diagenesis and entering Cu-rich oxidant fluids replacing Cu for Fe in the pyrite and forming Cu-sulfides and hematite and mineralization. The Kahak copper deposit shows high similarities in geometry, host rock, mineralogy, texture and structure and genetic model with the Manto-type copper deposits worldwide.
Original Research Paper
Stratigraphy and Palaeontology
kiana kiarostami; Darioush Baghbani; Seyed Mohsen Aleali; Seyed Ali Aghanabati; Mohammad Parandavar
Abstract
Lithostratigraphy and biostratigraphy studies on the Sarvak Formation in type section (Tang- e Sarvak, Northwest of Behbahan) show that this Formation has 710 meter thicknesses that divided in to four lithostratigraphic units. The Sarvak Formation in type section rests on the Kazhdumi Formation conformably ...
Read More
Lithostratigraphy and biostratigraphy studies on the Sarvak Formation in type section (Tang- e Sarvak, Northwest of Behbahan) show that this Formation has 710 meter thicknesses that divided in to four lithostratigraphic units. The Sarvak Formation in type section rests on the Kazhdumi Formation conformably with gradational contact (black shales and black argillaceous limestone) and under the Gurpi Formation with disconformity boundary. In this study 8 genus and 9 species of planktonic foraminifera and 34 genera and 33 species of benthic foraminifera have been reported. Four biozones based on (wynd, 1965) and two biozone based on) Premoli Silva and Verga 2004) have been reported as follow; Four biozones based on Wynd 1965: 1- Favusella washitensis range Zone # 23,2- '' Oligostegina'' facies # 26,3- Rudist debris # 24, 4- Nezzazata– Alveolinids Assemblage Zone # 25, Tow biozones based on Premoli Silva and Verga 2004: 1-Muricohedbergella planispira Zone, 2-Ticinella primula Zone. It can propose an Albian- Cenomanian age for Sarvak Formation based on these biozones and also it can recognize Albian-Cenomanian boundary on occurrence of Muricohedbergella planispira and Whiteinella sp. in lower part of this Formation.
Original Research Paper
Petrology
zahra badrzadeh
Abstract
Abstract The studied Chaltian granitoid is located in the endpoint of the southern Sanandaj–Sirjan Zone. This pluton has Low-Al trondhjemitic composition with tholeiitic to transitional nature. The intrusion has been intruded in the early Mesozoic volcanic and sedimentary rocks. According to U-Pb ...
Read More
Abstract The studied Chaltian granitoid is located in the endpoint of the southern Sanandaj–Sirjan Zone. This pluton has Low-Al trondhjemitic composition with tholeiitic to transitional nature. The intrusion has been intruded in the early Mesozoic volcanic and sedimentary rocks. According to U-Pb SHRIMP age dating of zircon grains, this pluton was intruded at the 187.5 ±3.2Ma ago. Studied pluton has low Al2O3, Sr/Y, (La/Yb)N ratio and less fractionated REE pattern. In the primitive mantle normalized spider diagrams, studied samples show enrichment of LIL elements such as K, Rb, Ba and Th relative to HFS elements and has negative anomaly in Ta, Nb and Ti elements, which are considered characteristic of magmas generated in subduction related settings. In terms of their origin, based on geological and geochemical characteristics, trondhjemitic melt has been generated by low pressure dehydration melting of amphibolitic source in an continental extensional tectonic setting related to subduction environment.
Original Research Paper
Stratigraphy and Palaeontology
s senemari
Abstract
In order to study biostratigraphy of the Pabdeh Formation in the Northeast Kazerun, Murdak section was selected. In this section, Pabdeh Formation is mainly consists of marl, shale and marly limestone. The study of calcareous nannofossils led to the recognition of 70 species and 28 genera. According ...
Read More
In order to study biostratigraphy of the Pabdeh Formation in the Northeast Kazerun, Murdak section was selected. In this section, Pabdeh Formation is mainly consists of marl, shale and marly limestone. The study of calcareous nannofossils led to the recognition of 70 species and 28 genera. According to the first and last occurrence of index species and assemblages fossil, the following biozones based on global standard zonations are identified: Discoaster multiradiatus Zone (NP9/CP8a/CNP11), Tribrachiatus contortus Zone (NP10/ CP8b-CP9a/ CNE1- CNE2), Discoaster binodosus Zone (NP11/ CP9b/ CNE3), Tribrachiatus orthostylus Zone (NP12/ CP10/ CNE4), Discoaster lodoensis Zone (NP13/ CP11/ CNE5), Discoaster sunlodoensis Zone (NP14/ CP12/ CNE6- CNE8), Nannotetrina fulgens zone (NP15/ CP13/ CNE9-CNE11), Discoaster tanii nodifer Zone (NP16/ CP14a/ CNE12-CNE15), Discoaster saipanensis Zone (NP17/ CP14b/ CNE15- CNE16), Chiasmolithus oamaruensis Zone (NP18/CP15a/CNE17-CNE18), Isthmolithus recurvus Zone (NP19/CP15b/CNE18-CNE19), Sphenolithus pseudoradians Zone (NP20/ CP15b/ CNE20), Ericsonia Subdisticha zone (NP21/CP16a-b/CNE21-CNO1), Helicosphaera reticulate Zone (NP22/ CP16c/ CNO2), Sphenolithus predistintus Zone (NP23/ CP17- CP18 / CNO3- CNO4). As a result of this study and based on the obtained biozones, the age of Pabdeh Formation in Murdak section, is Late Paleocene (Thanetian) to Oligocene (Rupelian-Chatian).
Original Research Paper
Economic Geology
Hossein Abasnia; M. H. Karimpour; Azadeh Malekzadeh Shafaroudi
Abstract
Damanghor area is located northern Bardaskan, Khorasan Razavi province, and structurally, it is a part of Taknar zone. Geology of the area includes of Taknar metamorphosed sedimentary rocks and metarhyolite, which is intruded by diabasic rocks as stoke and dyke. The texture of metarhyolies is porphyry ...
Read More
Damanghor area is located northern Bardaskan, Khorasan Razavi province, and structurally, it is a part of Taknar zone. Geology of the area includes of Taknar metamorphosed sedimentary rocks and metarhyolite, which is intruded by diabasic rocks as stoke and dyke. The texture of metarhyolies is porphyry and contains of quartz and feldspar, whereas diabas has ophitic texture and contain plagioclas, pyroxene, and hornblend. Age of metarhyolite and diabas determined 550 Ma (Neoprotrozoic) and 8.8 Ma (Miocene), respectively, using zircon U-Pb method. Metarhyolites have peraluminous nature and were formed at intracontinental rift. Low enrichment in LREE relative to HREE and Eu negative anomaly indicates the magma is formed at plagioclase stability depth. (87Sr/86Sr)i (0.700712), (143Nd/144Nd)i (0.511852), and εNdi (–1.51) values show source of magma was mantel or lower crust. Diabases have toleitic to metaaluminous nature and were formed at subduction zone. (87Sr/86Sr)i (0.710527), (143Nd/144Nd)i (0.512716), and εNdi (+1.7) values indicate magma is drived from partial melting of metasomatized mantle wedge by released fluid of subducted slab, which is assimilated with continental crust. Taknar formation acidic Neoprotrozoic magmatism, which is formed at rift setting, associated with Miocene basic magmatism, which is formed at subduction zone, reveals an insight of tectonomagmatic conditions of Taknar zone in different times.
Original Research Paper
Economic Geology
Rahimzadeh Bahman; M. Movahednia
Abstract
The Kamyaran manganese is located in the 20 km from NW of Kamyaran and south of Kurdistan province. In geological structure map these Mn-deposite are outcrops in Zagros and northern Sanandaj-Sirjan collision zone and close to Zagros ophiolites. In this area, Mn-mineralization occurs as regular lenses ...
Read More
The Kamyaran manganese is located in the 20 km from NW of Kamyaran and south of Kurdistan province. In geological structure map these Mn-deposite are outcrops in Zagros and northern Sanandaj-Sirjan collision zone and close to Zagros ophiolites. In this area, Mn-mineralization occurs as regular lenses and interlayers with radiolarian cherts within the Eocene radiolarite and shale. The present work has been done based on field geology, mineralogy and geochemistry characterization. Study of Mineralogy and texturally Kamyaran Mn-ores show two stage mineralization including Braunite and Okhotskite were formed singenetic and pyrolusite was formed diagenetic. The high rate of Si and rhadiolarite fossils in Mn-bearing cherts suggest that the Kamyaran Mn-deposit was formed in deep oceanic area. The Variable content of Mn/Fe and high rate of detector element such as Ba and Sr revel the hydrothermal source for mineralization. Despite, Existence rhadiolarite fossils, sub-bedding deposits and some geochemical characterization suggest the sedimentary origin for Kamyaran Mn-deposit.
Original Research Paper
Stratigraphy and Palaeontology
Zahra Hosseini Asgarabadi; Nasrollah Abbassi; Hassan Mohseni; Saeed Khodabakhsh
Abstract
The Pabdeh Formation (Paleocene to Oligocene in age) comprises alternation of marl and limestone with the Purple Shale at the base is well exposed on the flanks of the Kabir-Kuh. Thalassinoides, Rhizocorallium, Planolites, Chondrites, cf. Rosselia, Spirophyton and Zoophycos were found in the limestone ...
Read More
The Pabdeh Formation (Paleocene to Oligocene in age) comprises alternation of marl and limestone with the Purple Shale at the base is well exposed on the flanks of the Kabir-Kuh. Thalassinoides, Rhizocorallium, Planolites, Chondrites, cf. Rosselia, Spirophyton and Zoophycos were found in the limestone beds, among which trace fossils of Zoophycos group (Spirophyton and Zoophycos) are the most abundant. Structural variations of trace fossils of Zoophycos group were utiliized for recognition of five morphotypes including Rhizocorallium-shaped, branched Zoophycos, Spirophyton, short and fan-shaped lobate Zoophycos and long lobate Zoophycos morphotypes. Occurrence of these morphotypes in the studied sections implies an evolutionary trend, i.e. Rhizocorallium-shaped and branched Zoophycos morphotypes are developed in the lower parts of studied sections, whereas Spirophyton morphotype, is arranged in the mid-part of the Pabdeh Formation. Finally, short and fan-shaped lobate and long lobate Zoophycos morphotypes are abundant in the upper part of the formation. Seemingly, these morphotypes variation were adopted with switch of stable and calm water to unstable and relatively high energy environments.
Original Research Paper
Remote Sensing
N. Namazi; M. R. Jafari; A. R. Jafari Rad; A. Khakzad
Volume 29, Issue 113 , November 2019, Pages 221-228
Abstract
The study area (Pasghaleh) is located North of Tehran and is part of the Central Alborz Mountain Range. Pasghaleh deposit between coordinates 51º 25´15 ̎ up to 51º 25´ 54̎ Eastern longitude and 35º 49´42 ̎ up to 35º 50´15 ̎ Northern latitude in North ...
Read More
The study area (Pasghaleh) is located North of Tehran and is part of the Central Alborz Mountain Range. Pasghaleh deposit between coordinates 51º 25´15 ̎ up to 51º 25´ 54̎ Eastern longitude and 35º 49´42 ̎ up to 35º 50´15 ̎ Northern latitude in North of Tehran, in the geological sheet with a scale of 1:100000 Tehran and is located East of the Pasghaleh village. Intrusive bodies in this area with age after the Eocene in penetrating Eocene volcanic and pyroclastic units and have altered these units. For mapping minerals and explore the alteration patterns together with Polymetal mineralization in the metallogenic zone Pasghaleh, for sine satellite ASTER and ETM spectral processing and interpretation. According to remote sensing data, it leads to the appearance of Kaolinite and Montmorillonite minerals (Argillic alteration index), Chlorite, Epidote and Calcite (Propylitic alteration index), Muscovite (Sericite alteration index) and Gossan in the range studied. Major mineralization in the region in acid Tuffs altered and scattered. The lithology of this region including pyroclastic rocks of Karaj Formation with Eocene age. Sulfuric minerals observed Pyrite, Chalcopyrite, Sphalerite and Galena. In the whole region Pyrite expands but Lead mineralization, Zinc, Copper, Gold and Silver which process is parallel to the general layering of classes Tuff Silica altered- Feldspathic- Pyrite slightly observed. Pyrite form syngenetic among the Tuffs.Tuffs in formation stage and in the stage of diagenesis, the alteration process Sericitic, Kaolinite and or Chlorite have tolerated. In terms of construction, altered zone mineralize Pasghaleh as a lens and layers plate form between rock units Dacite, Rhyodacite are formed. Based on the study of remote sensing data, presence of alterations Sericite, Argillic and Propylitic (the presence of Chlorite and Epidote) proven in the region, consequently by putting together these alterations to one another, it can be attributed to the alteration pattern of Kuroko Massive sulfide deposits.
Original Research Paper
Stratigraphy and Palaeontology
Meysam Shafiee Ardestani; Mohammad Vahidinia
Abstract
Apertural protective structures of the planktonic foraminifera in the Abderaz Formation have been studied in order to determine seal level changes in 4 stratigraphical sections including: Abderaz village, Muzduran pass, Padeha village and Shorb . Lithological study of the Abderaz Formation shown that ...
Read More
Apertural protective structures of the planktonic foraminifera in the Abderaz Formation have been studied in order to determine seal level changes in 4 stratigraphical sections including: Abderaz village, Muzduran pass, Padeha village and Shorb . Lithological study of the Abderaz Formation shown that Shorab section (east of the kopeh-Dagh basin) with 374 meters and Padeha village section with 602 meters represent minimum and maxiumum thickness, respectively. A total of 77 planktonic foraminifers species belonging to 19 genera, have been identified in studied sections. Eight Apertural protected plates have been recognized in the umbilical side of the distinguished planktonic foraminifera. Besides, 4 porticus structures (Simple lip, Tooth like-Porticus, Spiral Porticus, Imbricate Porticus) belonging to the morphotype 2 and 3, three Tegillum structures (Roll-type Tegillum, Strap-Shape Tegillum, Sheet like-Tegillum) belonging to the morphotype 3, and one Lip structure belonging to the morphotype 1, as well as their frequency have been recognized. Statistical analysis of protected structures of the umbilical area have been demonstrated that unlike to the imbricate porticus and sheet like Tegillum, the lip and simple lip structures show the highest frequency, indicating that the Abderaz Formation deposited in the relative shallow marine environment.
Original Research Paper
Petrology
Asma Nazarinia; Seyed Mohsen Mortazavi; Mohsen Arvin; Mohammad Poosti
Abstract
The Oligocene Sarduiyeh batholith with NW-SE trend is located in the southeast of the Urumieh-Dokhtar magmatic zone in the Kerman province. This batholith intruded into the Eocene volcanic rocks that comprises of andesite, andesite basalt and subordinate basalt with pyroclastics rocks. The batholith ...
Read More
The Oligocene Sarduiyeh batholith with NW-SE trend is located in the southeast of the Urumieh-Dokhtar magmatic zone in the Kerman province. This batholith intruded into the Eocene volcanic rocks that comprises of andesite, andesite basalt and subordinate basalt with pyroclastics rocks. The batholith consists of acidic-intermediate rocks such as diorite, tonalite, granodiorite and monzogranite. Mineral Chemistry of plagioclase crystals indicate that their composition varies between oligoclase and andesine with An 24-43 and calcic amphibole have magnesiohornblende compositions. Field, petrological and geochemical studies show that the Sarduiyeh batholith magma is I-type, metaluminous to weakly peraluminous and its belonging to calc-alkaline series. On the primitive mantle-normalized spider diagram, all samples are enriched in large ion lithophile elements such as U, K, Pb and Sr and depleted in high field strength elements such as Ti, Ta and Nb which are characteristics of the volcanic arc setting formed in an active continental margin. Based on geochemical studies, the Sarduiyeh batholith formed as a result of partial melting from metabasic rocks of lower crust.
Original Research Paper
Petrology
Shahram Khalili Mobarhan; sajjad khosravimashizi
Abstract
The Qale Gabra plutonic rocks has upper Jurassic age and intruded to the lower Jurassic Sedimentary rocks. Based on Field geology, mineralogy and geochemistary studies, the lithology composition of the area consists of granodiorite, monzogranite, syenogranite, granite rich in quartz and diorite-gabbro. ...
Read More
The Qale Gabra plutonic rocks has upper Jurassic age and intruded to the lower Jurassic Sedimentary rocks. Based on Field geology, mineralogy and geochemistary studies, the lithology composition of the area consists of granodiorite, monzogranite, syenogranite, granite rich in quartz and diorite-gabbro. geochemical diagrams, shows a mix acting of magmatic differentiation ,assimilation, mixing and contamination phenomena . According to genetical classification it belongs to I type and Magnetite series. Tectonic setting discrimination diagrams shows relation of this mass with VAG and based on other geochemical data it has a Metaaluminus-Peraluminus and Calc Alkaline with low postassium affinity. LREE and LILE enrichment and Nb , Ti depletion may be has been occurred for a crustal contamination in a subduction zone. As it located on Urmia-Dokhtar magmatic belt is seems that, This area is a product of subduction of Neothetys under central Iranian continental crust. Keyword: Qale Gabra,Granitoid , Geochemistry, mixing,fractional crystalization,contamination, Continental Subduction zone , Jiroft, Kerman province.
Original Research Paper
Stratigraphy and Palaeontology
Fateme Mahdikhani; Mahmoud Reza Majidifard; T. Mohtat; L. Bakhshande; M. Zamanipedram
Abstract
In order to study the biostratigraphy and lithostratigraphy of the K/Pg boundary two sections was considered. They are the Kuh-e Zaluband and Kuh-e Hunu sections in east of Khur (Esfehan Province). At the Kuh-e Zaluband section has a maximum thickness of 100 m, consisting of marl, limestone, sandy limestone, ...
Read More
In order to study the biostratigraphy and lithostratigraphy of the K/Pg boundary two sections was considered. They are the Kuh-e Zaluband and Kuh-e Hunu sections in east of Khur (Esfehan Province). At the Kuh-e Zaluband section has a maximum thickness of 100 m, consisting of marl, limestone, sandy limestone, sandstone and conglomerate and in the Kuh-e Hunu consisting of marl, limestone and sandy limestone. The lower part of the sections belonging to Farrokhi formation and upper part to Chupanan formation. Based of biostratigraphy at the study sections, summing up 88 thin sections were collected, among which the foraminifera with 17 specimens clearly predominate and belonging to 31 genera. Based on the foraminifera the age of the upper part of Farrokhi formation in the investigated area ranges Late Maastrichtian and Late Paleocene for lower part of Chupanan formation. Based on the paleontology, lithology and facies, there is disconformity in Cretaceous-Paleogene boundary in Kuh-e Zaluband and paraconformity in Kuh-e Hunu.
Original Research Paper
Sedimentology
Gholamreza Hosseinyar; Reza Moussavi-Harami; Iraj Abdollahi fard; Asadollah Mahboubi; Hamidreza Mosaffa
Abstract
Identification of falling-stage system tracts (FSST) in sequence stratigraphy has important role in sequence boundary recognition and exploration researches. However, formation and preservation chance of its related facies in the fluvial successions is very low. This study pays to signs and evidence ...
Read More
Identification of falling-stage system tracts (FSST) in sequence stratigraphy has important role in sequence boundary recognition and exploration researches. However, formation and preservation chance of its related facies in the fluvial successions is very low. This study pays to signs and evidence of identification of the FSST in sequence stratigraphy with an example from Lower Cretaceous fluvial Shurijeh Formation in the east Kopeh Dagh Basin. Integration of 3D seismic data with boreholes data from seven wells and four outcrop sections (Shurijeh Village, Anjeer-Bulagh, Mozduran Pass and Qorqoreh) used in this study. Results show that during Late Jurassic-Early Cretaceous marine regression fine-grained and hybrid carbonate-siliciclastic facies in the base of the Shurijeh Formation are belong to falling stage system tract. These facies deposited in low energy condition in flood plain and coastal plain, related to the shoreline trajectory. Based on seismic stratigraphic study, fluvial system tocks place and channels created in the basin, during sea/base level forced regression. Quantitative seismic geomorphological analyses indicate that existed channels were hydraulically as bypassing channels.
Original Research Paper
Economic Geology
Simindokht Younesi; Mohammadreza Hosseinzadeh; Mohsen Moayyed
Abstract
Mineralogy of oxide zone as clue about past climate reveals occurrence of supergene enrichment processes in Mahour Zn-Cu-(Pb-Bi-Ag) mineralization, in central Lut, during two stages: In first stage that supergene processes have occurred from meteoric waters in an arid climate during Oligocene to Upper ...
Read More
Mineralogy of oxide zone as clue about past climate reveals occurrence of supergene enrichment processes in Mahour Zn-Cu-(Pb-Bi-Ag) mineralization, in central Lut, during two stages: In first stage that supergene processes have occurred from meteoric waters in an arid climate during Oligocene to Upper Miocene, leached capping contains jarosite, natrojarosite and goetite in various ratios and less hematite and sulfur has formed with supergene argillic alteration with quartz, alunite, kaolinite, montmorilonite, and gypsum. In response to neutrialization of solutions, an abundance of smithsonite and malachite with neotocite, greenokite /hawleite and minor azurite and silicate, phosphate and arsenate minerals precipitated in oxide zone and immature sulfide enrichment generated. In second stage, atachamite, paratacamite and chrysocolla have been formed through the interaction of saline waters and preexisting copper oxides after the onset of hyperaridity at Pliocene, and have been preserved since that time. Mineralogy features of leached capping provide insighs into hypogene ore mineral and alteration types and indicate sufficient acid has not been produced for effective leaching of Cu and hence, do not suggest extensive chalcocite enrichment under water table. An interpretation that mineralogy of oxide zone is also illustrative of it and results from exploration drill holes confirm it. With respect to style of Mahour polymetal mineralization and similar mineralizations in district, detail investigation of oxide zone and mapping leached caps in deposit and district scale can be used as suitable exploration tool in the search for conceal ore deposits..
