Lower Cretaceous carbonate successions outcrop extensively along the northern Tethyan margin in Kopet-Dagh (NE Iran) and Yazd Block (Central Iran). These units are not well constraint terms of stratigraphic, sedimentological, geochemical, paleobiogeographic view point. To improve our knowledge, a detailed multidisciplinary study has been presented on two roughly coeval stratigraphic different a...

at the boundary between jurassic and cretaceous, because of late kimmerian movements, the sea ragressed from many areas of north and cantral iran, and many continental areas rose, which included a number of differentiated basins. the boundary between jurassic and cretaceous in these parts of iran is usually marked by a big diastem or by red, clastic and evaporitic sediments. the whole or part o...

The Tirgan Formation (Barremian – Aptian) is exposed in the Kopet Dagh in northeast Iran. One stratigraphic section in Zavin was measured with a thickness of 110 meters. This Formation in section consists of three parts (including lower carbonate, limy shale – marl and upper carbonate rocks). Based on the study of 94 thin sections, 10 carbonate and 2 siliciclastic lithofacies have been identifi...

Isotope data from bulk carbonates, micrite, marine calcite cements, non-skeletal grains and brachiopods indicate deposition of a wide spectrum of warm to cold water carbonates during the Ordovician and the Jurassic. This isotopic interpretation is supported by warm to cold climatic models proposed for the Ordovician and the Jurassic. These carbonates formed during the Greenhouse mode (condition...

The geographic distribution of Astragalus (Fabaceae) in Iran was analyzed using a database of 7606 georeferencedobservations. Astragalus occurs in all provinces of Iran, but 88% ofthe observations are in five provinces including Tehran, West-Azerbaijan, Esfahan, Kordestan, and Khorasan-e Razavi.Most species are rare and narrowly endemic: Thelargest distance between two observations of the same ...

The aim of this study is to analyze the assemblage of trilobites in the Silurian sequences of Iran by exploring stratigraphic section of the Silurian Niur Formation (Asadli section).  Based on comprehensive field studies and laboratory investigations three Trilobite genera were identified in the study area including Calymene blumenbachii, Gravicalymene convolva, Dalmanites brevigladiolus </...

Paleoclimatic investigation of loess-paleosol sequences from northern Iran is important for understanding past changes in a region highly sensitive to shifts precipitation, and along potential routes human migration. Here, we present carbon oxygen isotopic compositions bulk carbonate (? 13 C bc ? 18 O , respectively) coupled with particle size distributions samples the Mobarakabad section, Iran...