Ichnology and sedimentology of a tide-influenced delta in the Ordovician from the northeastern Alborz range of Iran (Kopet Dagh region)

Lethaia ◽  
2015 ◽  
Vol 49 (3) ◽  
pp. 327-350 ◽  
Author(s):  
Aram Bayet-Goll ◽  
Carlos Neto de Carvalho
Keyword(s):  
Kopet Dagh ◽  
Alborz Range

The first Early Ordovician graptolites and marine incursions in eastern Alborz, Iran

2021 ◽  
pp. 1-14
Author(s):  
Adrian W. A. Rushton ◽  
Mansoureh Ghobadi Pour ◽  
Leonid E. Popov ◽  
Hadi Jahangir ◽  
Arash Amini
Keyword(s):  
Northern Iran ◽  
Early Ordovician ◽  
Lower Ordovician ◽  
Shale Formation ◽  
Kopet Dagh ◽  
Semnan Province

Abstract Graptolites have been collected from sections through Lower Ordovician strata in northern Iran. At the Saluk Mountains, in the Kopet–Dagh region, mudrocks yielded fragmentary tubaria of Rhabdinopora sp. cf. R. flabelliformis, indicating the presence of lower Tremadocian strata there; stratigraphically, they lie between two limestone beds with the euconodont Cordylodus lindstromi. At Simeh–Kuh in the eastern Alborz Mountains (Semnan Province), upper Tremadocian – lower Floian strata include laminated dark mudstones that contain restricted graptolite faunas, mainly of small declined didymograptids; these are thought to represent incursions of plankton during periods of marine highstands. The lower major flooding surface in Simeh–Kuh coincides with an invasion of the graptolite biofacies and an incursion of Hunnegraptus? sp.; the second major flooding surface is associated with an incursion of Baltograptus geometricus. They were most probably synchronous with those in the lower part of the Hunnegraptus copiosus Biozone and at the base of the Cymatograptus protobalticus Biozone in the of the Tøyen Shale Formation succession of Västergötland, Scandinavia, suggesting that observed characters of sedimentation were eustatically controlled.

scholarly journals Barremian-Aptian Dasycladalean algae, new and revisited, from the Tirgan Formation in the Kopet Dagh, NE Iran

2010 ◽  
Author(s):  
Abad M. TAHERPOUR KHALIL ◽  
Marc André CONRAD ◽  
Ali Asghar ARYAEI ◽  
Ali Reza ASHOURI
Keyword(s):  
Kopet Dagh ◽  
Ne Iran

Iris ferdowsii (Iridaceae), a new species of section Regelia from northeast of Iran

Phytotaxa ◽  
2017 ◽  
Vol 291 (3) ◽  
pp. 192 ◽  
Author(s):  
FARSHID MEMARIANI ◽  
MOHAMMAD REZA JOHARCHI
Keyword(s):  
New Species ◽  
Conservation Status ◽  
Morphological Characters ◽  
Middle Asia ◽  
East Of Iran ◽  
Kopet Dagh ◽  
A New Species ◽  
Ne Iran

Iris ferdowsii is described and illustrated as a new species from Khorassan-Kopet Dagh floristic province in NE Iran. It is closely related to the rhizomatous bearded irises of I. sect. Regelia. The species of this section are distributed mainly in the east of Iran, Afghanistan, west of Pakistan and Middle Asia. Diagnostic morphological characters, and notes on distribution, habitat and conservation status of the new species are provided.

scholarly journals Thermal maturity of the Upper Triassic–Middle Jurassic Shemshak Group (Alborz Range, Northern Iran) based on organic petrography, geochemistry and basin modelling: implications for source rock evaluation and petroleum exploration

2011 ◽  
Vol 149 (1) ◽  
pp. 19-38 ◽  
Author(s):  
ALI SHEKARIFARD ◽  
FRANÇOIS BAUDIN ◽  
KAZEM SEYED-EMAMI ◽  
JOHANN SCHNYDER ◽  
FATIMA LAGGOUN-DEFARGE ◽  
...  
Keyword(s):  
Middle Jurassic ◽  
Vitrinite Reflectance ◽  
Upper Triassic ◽  
Petroleum Exploration ◽  
Thermal Maturity ◽  
Northern Iran ◽  
Carbonaceous Shales ◽  
Petroleum Generation ◽  
Central Eastern ◽  
Alborz Range

AbstractOrganic petrography and geochemical analyses have been carried out on shales, carbonaceous shales and coals of the Shemshak Group (Upper Triassic–Middle Jurassic) from 15 localities along the Alborz Range of Northern Iran. Thermal maturity of organic matter (OM) has been investigated using vitrinite reflectance, Rock-Eval pyrolysis and elemental analysis of kerogen. Reflectance of autochthonous vitrinite varies from 0.6 to 2.2% indicating thermally early-mature to over-mature OM in the Shemshak Group, in agreement with other maturity parameters used. The shales of the Shemshak Group are characterized by poor to high residual organic carbon contents (0.13 to 5.84%) and the presence of hydrogen-depleted OM, predominantly as a consequence of oxidation of OM at the time of deposition and the hydrogen loss during petroleum generation. According to light-reflected microscopy results, vitrinite/vitrinite-like macerals are dominant in the kerogen concentrates from the shaly facies. The coals and carbonaceous shales of the Shemshak Group show a wide range in organic carbon concentration (3.5 to 88.6%) and composition (inertinite- and vitrinite-rich types), and thereby different petroleum potentials. Thermal modelling results suggest that low to moderate palaeo-heat flow, ranging from 47 to 79 mW m−2 (57 mW m−2 on average), affected the Central-Eastern Alborz basin during Tertiary time, the time of maximum burial of the Shemshak Group. The maximum temperature that induced OM maturation of the Shemshak Group seems to be related to its deep burial rather than to a very strong heat flow related to an uppermost Triassic–Liassic rifting. The interval of petroleum generation in the most deeply buried part of the Shemshak Group (i.e. Tazareh section) corresponds to Middle Jurassic–Early Cretaceous times. Exhumation of the Alborz Range during Late Neogene time, especially along the axis of the Central-Eastern Alborz, where maximum vitrinite reflectance values are recorded, probably destroyed possible petroleum accumulations. However, on the northern flank of the Central-Eastern Alborz, preservation of petroleum accumulations may be expected. The northern part of the basin therefore seems the best target for petroleum exploration.

Description of Dysdera zonsteini n. sp. (Arachnida: Araneae: Dysderidae) from Turkmenistan

Zootaxa ◽  
2021 ◽  
Vol 4938 (5) ◽  
pp. 588-594
Author(s):  
DRAGOMIR DIMITROV
Keyword(s):  
New Species ◽  
Species Group ◽  
The South ◽  
Kopet Dagh ◽  
A New Species

A new species of Dysdera Latreille, 1804 is described from the South-Western Kopet Dagh, Turkmenistan, on the basis of both sexes. The species is compared to its closest congener Dysdera kronebergi Dunin, 1992, and tentatively assigned to the D. asiatica species-group. 

Sign in / Sign up

Export Citation Format

Share Document