Oligocene

Key words: Erycine snakes, Calamagras, Geringophis, Early Oligocene, Badlands National Park, SD

The aim of the paper is (1) to find structural support or the supposed unique biomineralization system of cirratulids, (2) to compare cirratulid skeletal structures with phylogenetically close sabellids and serpulids n order to find similarities, and (3) to find whether he skeletal ultrastructures of cirratulids have evolved ince the Oligocene. The collection is housed at the Zoological Museum, University of Amsterdam (ZMA), and at the Museum of Natural History, University of Tartu (TUG).

Orogenic movements in the Late Eocene-Early Oligocene resulted in the creation of lagoonal to continental sedimentary regime characterized by detritic-evaporitec sediments of the Lower Red formation.

Les assemblages de foraminiferes benthiques recuperes des echantillons de carottes laterales dans la section de l'Oligocene, presentent une diversite d'especes exceptionnellement faible, malgre le nombre eleve de specimens.

The mammalian fauna of the White River Oligocene. Part IV.

MGS Locality 106 is one of the best preserved Oligocene fossil sites in the United States.

The animal was believed to have lived about 30 million years ago during the oligocene period.

Until Meyer's arrival, the fossilization at the site was generally attributed to huge volcanic ashfalls that covered an Oligocene lake and its surrounding, subtropical forest.

Among the many achievements was a new understanding of the early Cenozoic period of climate change known as the Paleogene era, which is further subdivided into three epochs, the Paleocene (57 to 65 million years ago), Eocene (35 to 57 million years ago), and Oligocene (25 to 35 million years ago).

Generally, the sedimentary sequence ranging in age from Eocene to Recent is exposed in the area with marked unconformities between late Eocene to Oligocene. The sequence becomes older to younger as we move from south to north direction.

The early stages of the Oligocene marked a turning point in the tectonic development of the Caucasus.