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Isotopic chemostratigraphy of the Permian-Triassic boundary in Zagros Mountains, Aligoudarz, Iran
Lithological sequences from the Permian-Triassic transition
in Middle Zagros, Iran are composed of the Dalan Formation
limestone with shelly fauna, Khaneh Kat Formation with two
stromatolite units at the lowermost part as well...
High resolution stratigraphy and extinction patterns of the Ammonoidea at the Permian-Triassic boundary of NW Iran
The classical Permian-Triassic (P-Tr) boundary sections in the vicinity of Julfa (NW Iran) have high potential for the study of the end-Paleozoic extinction event. The lithostratigraphic record of the P-Tr boundary beds in the Julfa area is rather...
Lithostratigraphy and carbonate microfacies across the Permian–Triassic boundary near Julfa (NW Iran) and in the Baghuk Mountains (Central Iran)
Permian–Triassic boundary sections in the Julfa (NW Iran) and Abadeh (Central Iran) regions display
a succession of three characteristic rock units, (1) the Paratirolites Limestone with the mass extinction horizon at its top, (2...
Permian Calcareous algae from the Khachik Formation at the Ali Bashi Mountains, NW of Iran
Micropaleontological investigations on Permian successions in the NW of Iran based on algae led to the determination of taxa belonging to some families such as Ungdarellaceae (Ungdarella uralica), Gymnocodiaceae (Gymnocodium bellerophontis...
Pre–mass extinction decline of latest Permian ammonoids
The devastating end-Permian mass extinction is widely considered to have been caused by large-scale and rapid greenhouse gas release by Siberian magmatism. Although the proximate extinction mechanisms are disputed, there is widespread agreement...
The Late Permian araxoceratid ammonoids: a case of repetitive temporal and spatial unfolding of homoplastic conch characters
The Wuchiapingian (early Late Permian) ammonoid family Araxoceratidae shows a morphological spectrum that is recurring in the three genera Araxoceras (early Wuchiapingian; Transcaucasus-Iran), Vedioceras (late Wuchiapingian; Transcaucasus...
Early Changhsingian (Late Permian) ammonoids from NW Iran
Early Changhsingian ammonoids from the Transcaucasus-NW Iranian region are poorly known. Here we revise the ammonoids of this interval based on new findings in sections of the Aras Valley and Ali Bashi Mountains of the ...
The Lilliput Effect in the latest Permian ammonoids from Iran
We studied the classical Permian–Triassic (P–Tr) boundary sections in the vicinity of Julfa (NW Iran) and in the Baghuk Mountain area (Central Iran). The youngest Permian ammonoid-bearing carbonate formation is the Paratirolites Limestone (four...
The role of microbial anaerobic respiration in the end-Permian mass extinction
Changes in plankton productivity have been connected with the end-Permian mass extinction. A box-model – proxy data comparison suggests that an increase of microbial sulfate reduction (MSR) can explain excursions in δ34SCAS and δ18OCAS...
Carbonate microfacies and δ13C and δ15N systematics across the Permian-Triassic boundary near Julfa (NW Iran)
Investigation of the sedimentary and geochemical characteristics of the Permian-Triassic (P-Tr) boundary beds is one approach to the study of the most dramatic extinction event in Earth’s history. In a new multidisciplinary project, carbon isotope...