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 ...

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...

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...

in this study, depositional environment and provenance of sandstones of the surijeh formation (lower cretaceous) in the abgarm section in the kopet-dagh basin are investigated. analysis of sedimentary facies in this section shows that there are two clastic (continental and coastal plain) and two carbonate (coastal plain) facies associations are present. the results of modal analysis and geochem...

the kalat formation is one of units in the kopet dagh sedimentary basin and so far have been studied by other fossils (case study) (palynomorphs, calcareous nanoplankton and foraminifera). according to the important ostracoda in diagnosis paleoecology and paleoenvironment, in this study, investigated ostracoda in shale units of the kalat formation in chahchaheh section have been studied for the...