Biostratigraphy and microfacies analysis of the Asmari Formation in SE of Aleshtar, Lorestan
S.
Arefifard
دانشگاه لرستان، دانشکده علوم پایه، گروه زمینشناسی
author
B.
Yousefi Yeganeh
دانشگاه لرستان، دانشکده علوم پایه، گروه زمینشناسی
author
M.
Amini Tari
دانشگاه آزاد واحد خرم آباد، دانشکده علوم، گروه زمینشناسی
author
text
article
2014
per
The Asmari Formation in the Sarab-e Narm setion in south-east of Aleshtar town was measured and sampled in order to study its foraminiferal faunas and microfacies. Based on the stratigraphical distribution of the larger benthic foraminiferas in the studies section two assemblage zones have been recognized. Assemblage zone I represents a Aquitanian age and includes Miogypsina barsaensis, Peneroplis farsensis, Elphidium sp., Nummulitids sp. and Schlumbergina sp., Assemblage zone II is characteristic of Burdigalian age which consists of Borelis melo curdica, Meandropsina iranica, Austrotrillina cf. howchini, A. cf. striata, A. cf. asmariensis and Dendritina rangi. This section lacks lower Asmari Formation. According to the petrographic analysis of the deposits, five microfacies types were identified. The Asmari Formation has been deposited on a carbonate ramp in which facies belts of middle ramp and inner ramp are distinguishable.
New Findings in
Applied Geology
Bu-Ali Sina University
2228-5873
8
v.
15
no.
2014
1
12
https://nfag.basu.ac.ir/article_797_1059a734cd9a9c9e7434b70e3ce098a2.pdf
Biostratigraphy of Campanian- Maastrichtian sediments in the north west Shiraz (Ghaleh Mountain)
M.
Parvaneh Nejad Shirazi
گروه زمینشناسی، دانشگاه پیام نور، صندوق پستی 3697- 19395، تهران، ایران
author
M.
Bahrami
گروه زمینشناسی، دانشگاه پیام نور، صندوق پستی 3697- 19395، تهران، ایران
author
M. Khazrak-Asli
Khazrak-Asli
دانشجوی کارشناسیارشد، دانشگاه پیامنور شیراز
author
text
article
2014
per
Tarbur Formation at Ghaleh Mountain with 760m thickness is consist of two different types facies: terrigenous (in lower part) and calcareous (in upper parts). Terrigenous part consists of shale, marl, sandstone, conglomerate together with marine and benthic foraminifera. Litological and paleontological characteristics of this part, in general, show a barrier and siliciclastic shoreline environment.
Calcareous section concluded of three parts: Lower part, middle part and upper part. Lower Calcareous part is consist of thin to medium bedded and middle part is consist of medium to thick bedded limestone which is rich of rudist and other benthic foraminifera. Upper part is consist of thick to very thick bedded limestone.
In order to biostratigraphy of Tarbur Formation, 72 samples are achieved that based on identified foraminifera, we recognized biozone Orbitoides & Omphalocyclus Assemblage Zone in this formation. Based on identified foraminifera, Tarbur Formation age is Campanian- Maastrichtian in this section.
New Findings in
Applied Geology
Bu-Ali Sina University
2228-5873
8
v.
15
no.
2014
13
19
https://nfag.basu.ac.ir/article_798_969cade4f03727f63a1dd38e5a6c8350.pdf
Microfacies and Paleogeography of Chehelkaman and Khangiran Formations (Paleogene) transition, east of Kopet-Dagh basin
A. A.
Siabeghodsy
دانشگاه ارومیه، دانشکده علوم پایه، گروه زمینشناسی
author
M. A.
Salahi
دانشگاه ارومیه، دانشکده علوم پایه، گروه زمینشناسی
author
B. Rivandi
Rivandi
دانشگاه فردوسی مشهد، دانشکده علوم پایه، گروه زمینشناسی
author
text
article
2014
per
Kopet-Dagh basin is located in north and northeast of Iran. Chehelkaman and Khangiran Formations are the most important formations of Paleogene settings. Upper parts of Chehelkaman Formation in the Chehelkaman Syncline section consist of sandy limestone, marl and limestone with transition contact into Khangiran Formation is conformable and transitional. In this study depositional condition of the top of Chehelkaman Formation and base of Khangiran Formation based on gastropod fauna and trace fossils were studied. These trace fossils in accosiation with tidal flat and lagoon facies that indicate of depositional in the shallow depth environment. Also in this study Globularia genus from Ampullinid gastropods for first time recognized of Kopet- Dagh basin.Because of this genus related with lagoon facies, can be indicate of shallow depth environment for the top of Chehelkaman Formation too. Paleobiogeography of this genus indicates of dependency of Kopet- Dagh basin to tethys realm. So far this genus reported of parts of Central Asian, Eastern Europe, Central Europe and Western Europe. This genus is in the top of Chehelkaman Formation of Kopet-Dagh basin, whearas this genus reported in the layer of post Early Eocene in Erope. This subject indicates migration direction of this genus from east toward west. So can be elicitation that the turan basin is the easternmost of the presence and occurrence of this taxon. In duration of this migration direction from east to west, Anatulian basin of Turkey exposure in the middle of this migration direction.
New Findings in
Applied Geology
Bu-Ali Sina University
2228-5873
8
v.
15
no.
2014
20
31
https://nfag.basu.ac.ir/article_799_434c1ffd2c5353ff128c058131946616.pdf
Petrography and tectonic setting of the mylonitic granitoids, SE-Qorveh (Kurdistan)
A. Torkian
Torkian
گروه زمینشناسی، دانشگاه بوعلیسینا، همدان
author
L.
Izadi Kian
گروه زمینشناسی، دانشگاه بوعلیسینا، همدان
author
M.
Rezaei
گروه زمینشناسی، دانشگاه بوعلیسینا، همدان
author
text
article
2014
per
The studied mylonitic granitoid is part of the granitiod batholite of south of Qorveh. Range of lithology of this complex is including granite, aplite with less abundant, biotite- granodiorite. These rocks are emplaced in a shear zone after they formed. Based on differences rate of strain, they are deformed as mylonitized and deformed rocks. Observations of field, petrographical and geochemical data imlpy they belong to I- type, poorly peraluminous and calalkaline series. Geochemical evidence of trace elements such as enrichment for large ion litophile elements (LILEs) and Pb, along with the negative anomaly field strength elements (HFSEs) and Ba and low ratios of Al2O3/(FeOt + MgO+TiO2) and meduim –high (Na2O+ K2O)/ (FeOt+ MgO+TiO2) indicate that origin of initial magma is continental crust that created in a margin of convergent plate. This magma may be formed by partial melting of protolites of lower crustal (e.g. greywacke).
New Findings in
Applied Geology
Bu-Ali Sina University
2228-5873
8
v.
15
no.
2014
32
42
https://nfag.basu.ac.ir/article_800_a538bff7719a44ce1a612a51f8d18cc3.pdf
Paleopalynology and Palebiogeography of Geirud Formation (Late Devonian) at the Kalariz section, northeast Damqan, Central Alborz
M.
Yousefi
دانشگاه آزاد اسلامی، واحد تهران شمال
author
H. Hashemi
Hashemi
دانشکده علوم زمین، دانشگاه خوارزمی
author
text
article
2014
per
The Geirud Formation at the Kalariz Section, northeast Damqan, comprises of 220 m of alternating basal conglomerate, quartzite, reddish sandstones followed by fossiliferous dark limestone with thin intercalations of shales. It disconformably overlies the Mila Formation and gradually succeeds the Mobarak Formation. Diverse, relatively well preserved palynofloras consisting of 26 species assigned to 13 genera of microphytoplanktons (4 genera and 9 species of Prasinophyte phycomata and 9 genera and 17 species of acritarchs), spores (21 species attributed to14 genera of exclusively trilette spores) and scoleocodonts occur in the material studied. Additionally cryptospores, albeit with far less abundance, are also recorded. Presence of such index fossil forms as: Cymatiosphaera perimembrana, Papulogabata annulata, Tornacia sarjeantii, Unellium lunatum, Unellium piriforme, Deltotosma intonsum, Geminospora lemurata, Densosporites spitsbergensis, Cymbosporites catillus and Punctatisporites planus allows attribution of Late Devonian age (Frasnian - early Famennian) to the pertinent material. Notable absence in the palynofloras studied of Retispora lepidophyta militates against any indication of late Famennian strata being present. Spores recorded from different rock samples are generally similar, denoting an almost uniform complexion unorthodoxically named assemblage zone I herein. Co-occurrence of spores and marine Palynomorphs indicates a marginal marine depositional setting. Spores- parent plants relationships alludes to presence of such diverse components as Progymnospermopsida, Cycadopsida, Zosterophyllopsida, Rhyniopsida, Filicopsida, Lycopsida, Barinopsida, Equisetopsida, close to the depositional site. Presence of Densosporites , Punctatisporites, Geminospora and Cymbosporites coeval testifies to domination of Lycopsida and Filicopsida in the coeval vegetation. Comparison between the palynofloras studied with those coeval host rocks from Iran indicates notable similarity with assemblages from the Alborz and Central Iran, and elswhere with those of the Western Australia. It could be said that Iran and Australia were probably located at comparable latitudes and also that migration routes might had been available between the Alborz and Central Iran at this time.
New Findings in
Applied Geology
Bu-Ali Sina University
2228-5873
8
v.
15
no.
2014
43
53
https://nfag.basu.ac.ir/article_801_d1b07967292c249f78842f75d544800f.pdf
Paragenetic equilibration and T-X CO2 estimation for formation of calc-silicate rocks from Jolbar area, south of Urmia
M. Mojarrad
Mojarrad
دانشگاه ارومیه، دانشکده علوم، گروه زمینشناسی
author
text
article
2014
per
Siliceous dolomites of the Jolbar area are metamorphosed during the intrusion of the Balestan alkali granite, Early Cenozoic. The main observed mineral paragenesis is Cal+Tlc+Srp±Tr±Di. Talc is the first mineral which is formed at the contact aureole and accompany the other calcareous minerals and some detrital quartz produced serpentine as a common mineral at the area. We plotted the position of chemical composition of the calc-silicates on the compatibility diagrams of the SCM system. Almost all of the samples are located on the Cal-Srp (Atg) tie line which shows that the above paragenesis was in the equilibrium with the whole rock chemistry. Considering that no olivine or brucite are crystallized and assuming 2kbar pressure for contact metamorphism, the highest estimated temperature at the aureole was 500±50 ºC. Serpentine is stable in the calc-silicate rocks, only if the composition of the present fluid is enriched by H2O. Therefore the X CO2 of fluid at the Jolbar area is considered to be <0.05.
New Findings in
Applied Geology
Bu-Ali Sina University
2228-5873
8
v.
15
no.
2014
54
66
https://nfag.basu.ac.ir/article_802_30c45f4d132187699efe4161c3e4a4e9.pdf
Geochemistry and tectonic environment of metaluminous granitoids of Sirjan, Urmia-Dokhtar magmatic belt, Iran
S. Jamei
Jamei
دانشگاه ارومیه، دانشکده علوم پایه، گروه زمینشناسی
author
A. Fazlnia
Fazlnia
دانشگاه ارومیه، دانشکده علوم پایه، گروه زمینشناسی
author
A.
Jafari
دانشگاه ارومیه، دانشکده علوم پایه، گروه زمینشناسی
author
text
article
2014
per
The Takht batholith is located to Sirjan and the southeastern part of the Urmia-Dokhtar magmatic belt. This complex has wide range of composition, including syenogranite, monzogranite, granodiorite, tonalite, quartz diorite, and gabbro. These rocks have clear contact surfaces with together, so that mafic rocks in margins and acidic rocks in centre of batholith were exposed. All mentioned units are I-type and have metaluminous and calc-alkaline nature, in composition. Abundance of hornblende, biotite and magnetite, absence of muscovite, garnet, cordierite..., wide variety of rocks, existence of magma mingling evidence, all are well-matched with their I-type nature. Linear trends of trace elements in harker diagrams and also identical trends of elements in spider diagrams, are indicated that the study rocks have genetic relationship with each other and have derived from the same parental magma. Enrichment of the study samples in LILE and LREE relative to HSFE and HREE show that these intrusions may have generated in an active continental margin from an enriched mantle source. In addition, negative anomalies of Nb and Ta along with enrichment of K, Rb, Th and Cs, implies to arc-related environment, as well as, interaction of crust and assimilation of crustal material during the process of their formation. Therefore, due to the Neotethys oblique subduction beneath the central Iran, basic parental magmashas formed from a metasomatized mantle. These melts during the ascent to upper crust horizons via assimilation and fractional crystallisation (AFC process) had formed the intermediate and felsic bodies. Finally the formed granitoids have intruded by deep faults especially Chahar Gonbad fault as compression injection.
New Findings in
Applied Geology
Bu-Ali Sina University
2228-5873
8
v.
15
no.
2014
67
82
https://nfag.basu.ac.ir/article_803_f7d4e95887322ca4b5053eda3ac02907.pdf
Physiography and Geomorphology of Tabarak Dam watershed, north of Quchan, and their effects to type of deposits
M. R.
Poursoltani
دانشگاه آزاد اسلامی، واحد مشهد، گروه زمینشناسی، مشهد، ایران
author
M.
Ghaemi Moghadam
دانشگاه آزاد اسلامی، واحد شاهرود، گروه زمینشناسی، شاهرود، ایران
author
text
article
2014
per
Tabarak Dam watershed is one of the main water supply of Atrak river, where located at north of Quchan. Geologically, Tabarak Dam watershed is a part of Kopet-Dagh basin.Watershed boundary is marked by Allah-Akbar Mountains and Zoo-Baran anticline. This watershed is divided to Zir-Abeh and Yadak sub-basins. Generally, due to present of different type of rock units, and tectonic effects, two areas, flat plain at Zir-Abeh sub-basin and mountain area at Yadak sub-basin have been formed. According to physiographic features, Tabarak Dam watershed is classified as a mean and elongate basin. The mean high of Tabarak Dam watershed is 1884.96 m, and the average gradient is about 23%. In addition, about 50% of basin shows 20-40 degrees slope. So, this basin is one of the high slope basins in this area. At Tabarak basin, some geomorphologic phenomenons, such as gully, rilly erosin, tallus, alluvial fan and landslide have been identified. Additionlly, different lithology has mostly caused to form drainage patterns such as denderitic and trellis. The identified sedimentary facies are gravelly (Gmm, Gcm), sandy (Sm) and muddy (Fl, Fm, Fr) facies, which are result of effect of physiography, geomorphology and lithology factors of study area.
New Findings in
Applied Geology
Bu-Ali Sina University
2228-5873
8
v.
15
no.
2014
83
97
https://nfag.basu.ac.ir/article_804_403704ef8f8d4cef6fddad4b7c464160.pdf