Atmospheric carbon dioxide concentrations (pCO2) beyond ice core records have been reconstructed from δ11B derived planktic foraminifera found in equatorial sediment cores. Here, I applied a cycle model over the Plio-Pleistocene to evaluate assumptions leading these numbers. During glacials times, simulated atmospheric pCO2 was unequilibrated with surface ocean by up 35 ppm while δ11B-based app...

[1] Carbon isotopes of foraminiferal tests provide a widely used proxy for past oceanographic environmental conditions. This proxy can be calibrated using live specimens, which are reliably identified with observations of cell ultrastructure. Observations of ultrastructures can also be used for studies of biological characteristics such as diet and presence of symbionts. Combining biological an...

Changes in coiling direction in foraminifera have been used extensively as proxy data for paleoclimates. However, most of the studies centred around plantkonic foraminifera, and various causes (including reproductive mode) were suggested for coiling direction changes. We explored the relationship between mode of reproduction and coiling directions in benthic foraminifera. Benthic foraminiferal ...

Coiling direction is a basic characteristic of trochospiral planktic foraminifera. Modifications in the coiling within ancient foraminiferal populations may reflect important changes evolution or environment, yet they remain scarcely discussed. Here we investigate fluctuations Morozovella assemblages from sections that span interval peak Cenozoic warmth, Early Eocene Climatic Optimum (EECO; ~53...

Abstract The Latest Danian Event (LDE, ~ 62.2 Ma) is characterized by global changes in the carbon cycle as indicated two negative ? 13 C excursions of up to 1‰. These shifts are accompanied a 2–3 °C warming both surface and deep waters based on benthic planktic foraminiferal 18 O measurements, LDE has, thus, been considered so-called hyperthermal event. event lasted for 200 kyr has identified ...

The Eocene Peñicas (Almería) and Harania (Málaga) stratigraphic sections from the Malaguide Complex (Betic Cordillera, South Spain) belonging to Mesomediterranean Microplate westernmost Tethys (about-35°N 0° 5°E according coordinates) have been studied. cover Cuisian middle Lutetian deposits, which show several lithofacies representing shallow marine platform realms. Based on fossiliferous asse...

This monograph has been compiled by members of the Paleogene Planktonic Foraminifera Working Group (hereafter referred to as the Working Group) of the International Subcommission on Paleogene Stratigraphy, International Union of Geological Sciences. It is the second such work in a projected series of three, the first being the Atlas of Paleocene Planktonic Foraminifera published by Smithsonian ...

the gurpi formation, at the type section (nw of masjed-soleiman) and in sabze-kuh (sw of borujen) are lithologically subdivided into 8 and 11 units, respectively. the study of planktonic foraminifera resulted in recognition of 7 biozones in lali area and 4 biozones in sabzeh-kuh area. these biozones are compared to the most standard biozones defined in tethysian domain. biozones i (globotruncan...

a micropaleontological study has been carried out on the samples collected from the sarv abad section, the oldest and only known jurassic sedimentary rocks cropping out in the moghan area. studied sequence consists of carbonates bounded at both base and top by clastic deposits. studied carbonate deposits provide an assemblage of benthic foraminifera as well as calcareous algae. the stratigraphi...