â â â  abstract â  in this study, 129 samples of the qom formation in kaltakeh, south east mahneshan, were investigated. the thickness of qom formation in the examined section is 565m and comprises of limestone, sandy limestone, marl, shale and argillaceous limestone . at this locality, the qom sediments disconformably overlies the lower red formation and underlies the upper red formation. amon...

Foraminifera have one of the best known fossil records among the unicellular eukaryotes. However, the origin and phylogenetic relationships of the extant foraminiferal lineages are poorly understood. To test the current paleontological hypotheses on evolution of foraminifera, we sequenced about 1,000 base pairs from the 3' end of the small subunit rRNA gene (SSU rDNA) in 22 species representing...

[1] Fossil foraminifera are critical to paleoceanographic reconstructions including estimates of past episodes of methane venting. These reconstructions rely on benthic foraminifera incorporating and retaining unaltered the ambient isotopic compositions of pore fluids and bottom waters. Comparisons are made here of isotopic compositions of abundant live and fossil foraminifera (Uvigerina peregr...

The spatial distribution of benthic foraminiferal assemblage of Nayband Bay and Haleh Estuary in the North-West of the Persian Gulf, was explored during 2011-2012 . The relationship between spatial pattern of foraminifera assemblages and the ambient factors (i.e. water temperature, salinity, pH, dissolved oxygen, sediment grain size distribution, sediment organic content, and CaCO3 concentrati...

[1] Reconstruction of oceanic nutrient concentrations in the past provides information about nutrient cycling and physical circulation and the role these processes have played in past climate changes. The Cd/Ca and Zn/Ca of benthic foraminifera have been used successfully to reconstruct past deep ocean nutrient concentrations. In this study we test the ability of benthic foraminiferal Cd/Ca and...

the qom formation in naragh area, with 185 meter thickness, is exposed about 25 km northeast of delijan. this formation in the studied area, lithologically, consists of shale, gravely limestone, and sandy limestone, with thin, medium to thick bedded and massive limestons. it disconformably covers the lower red formation and is covered by recent alluvium. in this research, the role of large fora...

In this study, four well-exposed outcrops of the Asmari Fm in the southeastern part of the Izeh Zone of the Zagros Mountains were measured and sampled. In this region, the Asmari Fm is Oligocene to Early Miocene in age as determined by large benthic foraminifera. Based on depositional geometries, biogenic contents and lateral and vertical variations of facies, three depositional models are prop...