M.R Partoazar; B Hamdi; S.A Aghanabati
Abstract
Foraminiferal contents of the Permian strata of the Kuh-e Baghvang in central Iran has been investigated. The section is located some 45Km Northwest of Tabas and south of Shirgeshtvillage. The Permian deposits of the Jamal Fm. with a thickness of 270 meters are underlain by the Sardar Fm. disconformably ...
Read More
Foraminiferal contents of the Permian strata of the Kuh-e Baghvang in central Iran has been investigated. The section is located some 45Km Northwest of Tabas and south of Shirgeshtvillage. The Permian deposits of the Jamal Fm. with a thickness of 270 meters are underlain by the Sardar Fm. disconformably and in turn overlain by the Lower Triassic deposits of Sorkh shale Formation. A total of 124 rock samples have been systematically taken from various layers for an accurate biostratigraphic study. Forty one genera and 48 species of Foraminifera and 10 generaand 12 species of Algae have also been determined through this study. According to the index fossils, geochronology of Member 1 and Member 2 of the Jamal Fm. is attributed to Early Murgabian. Moreover, according to the biostratigraphic study, some index fossils of Fusulinidae have been recorded and the following assemblage zones have been differentiated which are equivalent to international biozones of Leven(1975 and Ishii (1975). Paradunbarula – Geinitzina Assemblage Zone (Murgabian) Dagmarita – Paraglobivalvulina Assemblage Zone (Dzhulfian) Colaniella – Reichelina Assemblage Zone (Changxingian).
SH Habibimood; M.N Gorgij; KH Khosrotehrani; A Saidi; S.A Aghanabati
Abstract
The studied section is located in the vicinity of the village Daghal on the Zabol – Nehbandan road, 100 kilometersfrom Zabol. The strata under study are 55.57 meters thick here and lie nonconformably on the igneous rocks while the upper contact is now known. In this study the mentioned strata are ...
Read More
The studied section is located in the vicinity of the village Daghal on the Zabol – Nehbandan road, 100 kilometersfrom Zabol. The strata under study are 55.57 meters thick here and lie nonconformably on the igneous rocks while the upper contact is now known. In this study the mentioned strata are divided into four units lithologically. The results of macroscopic and microscopic studies and the microfacies analysis show that the strata were deposited in four sub-environments including, lagoon, tidal channel, submarine fans and open marine. The thickness and extent of the marine sub-environment is greater than the other sub-environments. The study of microfacies and their constituent sub-environments implies that the mentioned section is formed in a homoclinal carbonate ramp. This study indicates that during the late cretaceous there was a relatively shallow sea covered the area. The existence of microfossils such as Orbitoeides, Omphalosyclus and globutruncana indicates the age of Maastrichtian for the rock unit studied.
E Farshid; B Hamdi; V Hairapetian; S.A Aghanabati
M Joudaki; D Baghbani; S.A Aghanabati; B Soleimani; H Asilian; B Ariafar
Abstract
In order to biostratighraphy and to discover relationships between biozones of the Oligocene and lower Miocene strata in Zagros foreland basin, Zagros simply folded belt and High Zagros area, 10 stratigraphic sections along a transect from well "A" in Persian Gulf to Semirum section in High Zagros ...
Read More
In order to biostratighraphy and to discover relationships between biozones of the Oligocene and lower Miocene strata in Zagros foreland basin, Zagros simply folded belt and High Zagros area, 10 stratigraphic sections along a transect from well "A" in Persian Gulf to Semirum section in High Zagros were investigated. The study of more than 1500 thin sections resulted in identification of 32 genera and 54 species of benthonic foraminifera belonging to nine genera and 15 species of planktonic foraminifera. The recorded assemblages led to establishment of six biozones ranging in age from Oligocene to Early Miocene. Biostratighraphic correlation yielded clarification of relationship between biozones and sedimentary trends and discontinuities of the Oligocene and lower Miocene in Zagros basin in the areas.
M. Paknia; Habib Alimohammadian; M. R. Majidifard; J. Sabouri; A. Aghanabat
Abstract
The Golbini section comprising of continuous succession of sediments ranging in age from Triassic – Jurassic formations, is situated at 35 Km north – east of Jajarm city. On the bases of studies on Dalichai Formation at this section and at about Middle Jurassic (Bathonian–Callovian ...
Read More
The Golbini section comprising of continuous succession of sediments ranging in age from Triassic – Jurassic formations, is situated at 35 Km north – east of Jajarm city. On the bases of studies on Dalichai Formation at this section and at about Middle Jurassic (Bathonian–Callovian boundary), 3 Member, 31 Genus and 13 species of Ammonite, has been identified. For paleomagnetic analysis, with the help of portable coring machine, the total number of 155 oriented core samples were collected from limestone and clayey– limestone of this section. Then the samples were prepared for paleomagnetic analysis at Environmental and Paleomagnetic Laboratory based at Geological Survey of Iran, Tehran, Iran. The conducted paleomagnetic analysis include measurement of NRM, Susceptibility, Thermal and AF demagnetizing, Virtual Geomagnetic Polarity (VGP), identification of normal and reversal magnetic polarities and calculation of sedimentation rate. The obtained paleomagnetic results then composed with GPTS and also with proposed Bathonian–Callovian boundaries in Russia and Germany. This comparison reveals that the magnetic polarity of Golbini section is co-relatable with GPTS and also with Bathonian–Callovian boundary in Russia and Germany.
H. Pashaei; B. Hamdi; S. A. Aghanabati
Abstract
The studied section (Ruteh) is situated in central alborz, 31km north of Tehran.The thikness of measured section is 312m. The Elika Fm in Ruteh section is located 1 km far from the north of Ruteh village and 3 km far from the north of Fasham city. Lowermost strata seems to be parallel to ...
Read More
The studied section (Ruteh) is situated in central alborz, 31km north of Tehran.The thikness of measured section is 312m. The Elika Fm in Ruteh section is located 1 km far from the north of Ruteh village and 3 km far from the north of Fasham city. Lowermost strata seems to be parallel to rocks of the units which attribiuted to the Nessen Formation.and the upper boundary with Shemshak Fm. is obviously indicate disconformity. The Elika Fm. is subdivided to 9 lithological subunits.the lower part is consisting of thin-medium-bedded limestone. The upper part is mainly consisting of thick-bedded dolomite with intercalations of thin-bedded limestones. The Nessen Fm in this section subdivided to 2 lithological subunits. The lower part is consisting of 8 m bauxite-laterite and the upper part is mainly consisting of thin-medium-bedded limestones. Base of micropaleontology studies, 26 genus, 47 species and 1 subspecies of Foraminifers and conodont element have been recognized illustrating 1 Foraminifer biozone and 4 Conodont biozones. This Conodont biozones in Elika Fm consist of: Hindeodus parvus zone Pachycladina – Hadrodontina zone, Neospathodus cristagalli zone, Parachirognathus – Furnishius zone. According to Conodont data, carboniferous sequences in Ruteh Section were deposited from lower Griesbachian to Anisian-Ladinian in age. Also 8 genus and 14 species of Foraminifers have been described for the first time in uppermost of the bauxite – laterite ,so 1 Assemblage zones have been reported: Paraglobivalvulina mira – Pachyphloia iranica Assemblage zone. Comparision of color index Alteration (CAI) or postmortal facies Conodont elements with standard table presented by Epstein et al. (1977), show that CAI is 4 that indicate temporal interval of 190 – 300 with notation to this degree of temperature absence Oil and Gas in area.
E. Ghasemi-Nejad; M., Asadi; M. Shahmoradi; A. Aghanabati; T. Mohtat
Abstract
The Nayband Formation was sampled at Chal-Sefid and Zard mountains in central Iran, for palynology and palynostratigraphy in order to take the advantage of dinoflagellate cysts to locate the Triassic and so called Jurassic boundary. The Chal-Sefid section is located about 45 km southwest of Kashan city ...
Read More
The Nayband Formation was sampled at Chal-Sefid and Zard mountains in central Iran, for palynology and palynostratigraphy in order to take the advantage of dinoflagellate cysts to locate the Triassic and so called Jurassic boundary. The Chal-Sefid section is located about 45 km southwest of Kashan city and Zard Mountain some 70 km northeast of Esfahan. The studied strata attain a thickness of 1750 meters in Chal-Sefid and 1820 meters in Zard Mountain. They consists sandstone and shale beds. Totally 75 samples from Chal-Sefid and 22 samples from Zard Mountain were collected and treated in the Palynology laboratory of the Geological Survey of Iran. The recorded dinoflagellate cyst species were differentiated in four palynozones in Chal-Sefid and two palynozones in Zard Mountain as follows: Chal-Sefid section: Palynozone 1: Rhaetogonyaulax wigginsii, encompasses 160 meters of the section, suggesting an early to middle Norian age. Palynozone 2: Suessia listeri with a thickness of 140 meters, suggesting a middle Norian age. Palynozone 3: Hebecysta balmei encompasses 550 meters of the section, suggesting middle to late Norian age. Palynozone 4: Rhaetogonyaulax rhaetica with a thickneses of 900 meters suggests an early to middle Rhaetian age. Zard Mountain section: Palynozone 1: Hebecysta balmei, encompasses 442 meters of the section, suggesting a middle to late Norian age. Palynozone 2: Raetogonyaulax rhaetica, encompasses 491 meters of the section, suggesting an early to middle Rhaetian age. It is revealed that all the rock units investigated here are of late Triassic age and no evidence of Jurassic ages was identified.
J. Daneshian; D, Baghbani; S.A. Aghanabati; N. Norouzi
Abstract
Oligocene-Lower Miocene sediments at Nareh section, situated in SW Jahrum consists of limestone, argillaceous limestone, marl and evaporatic sediments with a rich association of planktonic and benthonic foraminifera. In lower part of this succession, the Pabdeh sediments with a thickness of 115m is composed ...
Read More
Oligocene-Lower Miocene sediments at Nareh section, situated in SW Jahrum consists of limestone, argillaceous limestone, marl and evaporatic sediments with a rich association of planktonic and benthonic foraminifera. In lower part of this succession, the Pabdeh sediments with a thickness of 115m is composed of shale, marl and intercalations of argillaceous limestone. The mentioned sediments continue through Late Eocene to Oligocene, which are overlain conformably by the Asmari Formation. The Asmari Formation consists of 250 m limestone and argillaceous limestone of which 210 m belongs to the lower Asmari and 40 m to middle Asmari. Argillaceous limestone and evaporatic-marly sediments of the Gachsaran Formation are overlain by the Asmari Formation. The Gachsaran Formation with a thickness of 510m is composed of three members of Chehel, Champeh and Moll. Pure and thick basal limestones of the Mishan Formation (Guri Member) with a thickness of 302 m, is situated above the Gachsaran Formation. Finally, Bakhtyari conglomerate lies uncomformably over the Mishan Formation. Variety of studied rock units in this section has caused different sedimentary environments, different facies and presence of abundant planktonic and benthonic foraminifera. By studying 203 samples including 193 hard and 10 washed samples, 34 genera and 47 species of benthonic foraminifera and 8 genera and 13 species of planktonic foraminifera, algae, briozoa and different macrofossils fragments were identified. Based on foraminiferal assemblages, the age of the lower part of the Pabdeh Formation is Late Eocene (Priabonian) and the upper part is Early Oligocene and the Asmari Formation is Oligocene (Late Rupelian-Chattian) to Early Miocene (Aquitanian). Also, the Gachsaran Formation belongs to Early Miocene (Aquitanian-Burdigalian) and the age of the Mishan Formation (Guri Member) is Late Miocene (Burdigalian) .On the basis of recognized foraminifera association, Nareh stratigraphical section can be correlated with first to fourth Biozones of biozonation of Adams and Bourgeois (1967) and 54,57,59,61,63 and 64 Biozones of Wynd (1965).
S. Shariati; S. A. Aghanabati; S. R. Mousavi Harami; S. Modabberi; M. H. Adabi
Abstract
Angouran Lead and Zinc Mining deposit is one of the biggest Lead and Zinc deposits of Middle East and one of five great mines of Iran according to the article of categorization of the mines of Iran. In addition to the diverse metal and non-metal mines, there are many industries and factories in this ...
Read More
Angouran Lead and Zinc Mining deposit is one of the biggest Lead and Zinc deposits of Middle East and one of five great mines of Iran according to the article of categorization of the mines of Iran. In addition to the diverse metal and non-metal mines, there are many industries and factories in this region which most of them were active and are as conversion industries of Zinc soil into the Concentrate or as factoring of Lead and Zinc Bar. The realized studies demonstrate that due to activation of existent industries in that region, the rate of some elements are in unusual level and show some fundamental environmental abnormalities. The environment of the region is mostly influenced by the accumulation of wastes and residues dispossessed as cake in the borders of the rivers and canals and open lands. These Cakes which as a matter of fact are the residues of proceeding of the flotation and melting the Lead and Zinc and the process of Concentrate factoring, may have lost the great amount of their Lead and Zinc in the industrial point of view, but as an environment view, those have a lot of Lead and Zinc many times more than allowed limits which are potentially toxic. At the other hand, by reduction of these elements, the densities of other elements are increasing. This means intensive effects which in this paper are going to be surveyed. The rates of these elements in some samples are reported exceeding to 10,000 ppm Lead and Zinc and Nickel and also 8,000 ppm Arsenic and 4,000 Cadmium. The studies also demonstrate that waste pool or the pools of residues are one of the most fundamental causes of dangers for the environment of the region. The rate of 200,000 ppm of Zinc and sometimes 2000 ppm of Lead and 20,000 ppm Nickel, also tha rate of some hundreds ppm of arsenic and even 200,000 ppm of Cadmium in the water and water deposits of the region are some of those dangers. The most of these abnormalities are seen in the sediments and water of the region, however the agricultural grounds are also influenced by these pollutions and are included some major abnormalities in term of the environment. This paper will exclusively review the allowed rate of the elements of Lead, Zinc, Cadmium, and Arsenic and survey the principal manners of access of these elements to the environment of region and also try to present some solution for the control and reduction of these rates.
M. A. Sina; A. Aghanabati; A. L. Kani; A. R. Bahadori
Abstract
Calcareous nannofossils are suitable for biostratigarphical studies since they are abundant, planktonic, rapidly evolving and largely cosmopolitan, especially in the late Cretaceous. In this regards, 131 microscopic slides from shale and marl sediments of Gurpi formation of Poldokhtar section with thickness ...
Read More
Calcareous nannofossils are suitable for biostratigarphical studies since they are abundant, planktonic, rapidly evolving and largely cosmopolitan, especially in the late Cretaceous. In this regards, 131 microscopic slides from shale and marl sediments of Gurpi formation of Poldokhtar section with thickness of 320 meters were collected. Out of this, 22 genera and 35 species were determined and their range chart is plotted. The distribution of nannofossil species indicates that there are 9 biozones in the study Poldokhtar section that can be separated, based on first occurrence (FO) of index species. They can be placed in CC18-CC26 of Sissingh (1977) time zones. On this basis, the age of sedimentation of this formation can be suggested to be from lower Companion to late Masstrichtian. In addition, presence of index species of low latitude in Poldokhtar section of Gurpi formation shows that this sedimentary basin was located in low latitude at the time of sedimentation.
A. Ghaderi; A. Aghanabati; B. Hamdi; A. Saeedi
Abstract
To study the Shirgesht Formation biostratigraphy in Kalmard Horst in relation to its conodont content, the Miyugodar (Miangodar) stratigraphic section was selected which is located in southwest of Tabas city. The Shirgesht Formation in the mentioned section is mainly composed of siliciclastic rock units ...
Read More
To study the Shirgesht Formation biostratigraphy in Kalmard Horst in relation to its conodont content, the Miyugodar (Miangodar) stratigraphic section was selected which is located in southwest of Tabas city. The Shirgesht Formation in the mentioned section is mainly composed of siliciclastic rock units and overlay unconformably on Kalmard Formation (attributed to Pre-Cambrian) and is overlain by Gachal Formation (Carboniferous). Thirty five rock samples were selected from appropriate rock units (Shirgesht and Gachal Formation). Samples were studied in laboratory for more details. According to the extracted conodont from Shirgesht Formation in Miyugodar section, the age of this formation can be regarded as Early Ordovician (Tremadocian – Arenigian). Three conodont assemblage zones were recognized in Early Ordovician units. They are: Cordylodus spp., Deltifer and Proteus Global Standard Conodont biozones. The recognized biozones are as followed:
1- Oneotodus - Drepanodus Assemblage Zone
2- Acodus deltatus - Protopanderodus Assemblage Zone
3- Acodus - Oistodus Assemblage Zone
R. Tavakoli; S. A. Aghanabati
Abstract
Tirgan and Sarchshmeh Formations, Aptian age, belong lithostratigraphically to Kopeh Dagh, for many reasons, with reference to lithology and biology contents that can be compared with Orbitolina limestone in the Central Iran. The similarities between these unites were the reason to compare the Mozdooran ...
Read More
Tirgan and Sarchshmeh Formations, Aptian age, belong lithostratigraphically to Kopeh Dagh, for many reasons, with reference to lithology and biology contents that can be compared with Orbitolina limestone in the Central Iran. The similarities between these unites were the reason to compare the Mozdooran section (Kopeh Dagh) with Baharestan section (Esfehan) by studying 71 lithology samples and 57 washing samples and found many similarities in lithology and biology.
The similarities of environments and type of sedimentation basins, would command this possibility that Aptian to Albian sea of the Kopeh Dagh was spread out through the Central Iran. This result can indicate the close relation between the Kopeh Dagh and Central Iran in the aforementioned time periods.
A. Ghaderi; A. Aghanabati; B. Hamdi; J. F. Miller
Abstract
The Shirgesht Formation is one of the fossiliferous units of Central Iran which in the type section is defined (informally) in the terms of 3 members. This formation is mainly composed of limestone, marl, siltstone, shale and dolomite, conformably overlay on the upper part of the Derenjal Formation with ...
Read More
The Shirgesht Formation is one of the fossiliferous units of Central Iran which in the type section is defined (informally) in the terms of 3 members. This formation is mainly composed of limestone, marl, siltstone, shale and dolomite, conformably overlay on the upper part of the Derenjal Formation with a gradual contact, composed of brachiopods limestone bearing (Billingsella limestone). The Shirgesht Formation is overlain by sandy limestone and volcanic rocks of the Niur Formation.
To do biostratigraphy studies on the first and second members of Shirgesht Formation in the type section, totally 99 rock samples were selected. The conodont fauna of lower part of its first member contain some species of Westergaardodina, Furnishina and prooneotodus which show an age of late Cambrian. Several species of Cordylodus, Oistodus, Drepanodus, Proconodontus and Paroistodus in distance of middle part of the lower member to the end of the second member represent an age of Tremadocian – Arenigian. According to conodont content of the first and second members of Shirgesht Formation, 7 conodont assemblage zones were determined in the type section which show an age of Late Cambrian – Early Ordovician. The recognized biozones are as follow:
1. Furnishina - Westergaardodina Assemblage Zone.
2. Proconodontus - Oneotodus Assemblage Zone.
3. Cordylodus proavus - Cordylodus oklahomensis Assemblage Zone.
4. Cordylodus lindstromi Assemblage Zone.
5. Cordylodus angulatus Assemblage Zone.
6. Drepanodus - Paltodus deltifer Assemblage Zone.
7.Paroistodus proteus Assemblage Zone.
The mentioned conodont assemblage zones are equivalent to Cordylodus spp., Deltiferand Proteus global standard conodont biozone. In contrast with the previous reports, the Cambrian – Ordovician boundary is located in the first member of the Shirgesht Formation. Thus, the Shirgesht Formation in type section is diachronous formation.
