a sequence of permian rocks crops out in northwest of khur in central alborz, north of iran. this sequence consists of the dorud (asselian-sakmarian), ruteh (artinskian-murgabian) and nesen (early djulfian) formations. the ruteh and nesen formations in alborz range were deposited in a shallow marine environment of the continental margin in the paleo-tethys. the ruteh formation with a thickness ...

Salt-marsh foraminifera have been used to reconstruct Holocene sea-level changes from coastlines around the world. In this work, we compile the results of surface foraminiferal surveys from fifteen study sites located on the east, south and west coasts of Great Britain, and the west coast of Ireland. These data, which comprise 236 samples and 84 species, are used to summarize the contemporary d...

A latest Maastrichtian global warming event, which began approximately 450 k.y. and ended about 22 k.y. prior to the K/T boundary, is associated with the poleward migration of the warm-water planktonic foraminifer Pseudotextularia elegans. The warming event was apparently inititated by greenhouse warming due to the main outpouring of the Deccan Traps in India and is now well documented in the N...

Understanding the interaction between climate and biotic evolution is crucial for deciphering the sensitivity of life. An enigmatic mass extinction occurred in the deep oceans during the Mid Pleistocene, with a loss of over 100 species (20%) of sea floor calcareous foraminifera. An evolutionarily conservative group, benthic foraminifera often comprise >50% of eukaryote biomass on the deep-ocean...

The relationship between seawater temperature and the average Mg/Ca ratios in planktic foraminifera is well established, providing an essential tool for reconstructing past ocean temperatures. However, many species display alternating high and low Mg-bands within their shell walls that cannot be explained by temperature alone. Recent experiments demonstrate that intrashell Mg variability in Orb...

—Foraminiferal tests are a common component of many marine sediments. The oxygen isotope ratio (δ18O) of test calcite is frequently used to reconstruct aspects of their life environment. The δ18O depends mainly on the isotope ratio of the water it is precipitated from, the temperature of calcification, and, to a lesser extent, the carbonate ion concentration. Foraminifera and other organisms ca...

planktonic foraminifera are useful in determining the relative age of the upper cretaceous strata. based on distribution of planktonic foraminifera in kuh-e siah section (212 m thickness), eight biozones have been recognized including dicarinella concavata interval zone (earliest santonian), dicarinella asymetrica total range zone (santonian to earliest campanian), globotruncanita elevata parti...

Raja Ampat is an archipelago of about 1,500 small islands located northwest off the Bird's Head Peninsula of Indonesia's West Papua province. It is part of the Coral Triangle, a region recognized as the "epicenter" of tropical marine biodiversity. In the course of a large-scale survey on shallow benthic foraminifera we have discovered one new genus and five new species of recent miliolid benthi...

We propose a new calculation method to better estimate the deep water ventilation age from benthic-planktonic foraminifera 14C ages. Our study is motivated by the fact that changes in atmospheric A14C through time can cause contemporary benthic and planktonic foraminifera to have different initial A14C values. This effect can cause spurious ventilation age changes tobe interpreted from the geol...

Chronologies for Late Quaternary marine sediment records are usually based on radiocarbon ages of planktonic foraminifera. Signals carried by other sedimentary components measured in parallel can provide complementary paleoclimate information. A key premise is that microfossils and other indicators within a given sediment horizon are of equal age. We show here that haptophyte-derived alkenones ...