Antarctica is home to numerous relatively young volcanoes from the Cenozoic era. According to one hypothesis, their activity was one of the factors driving the continent’s glaciation.

Drilling operations of the Cape Roberts Project took place between 1997 and 1999 offshore of Cape Roberts in the western Ross Sea, Antarctica. These were made possible due to a group effort by geoscientists from Australia, Germany, Italy, New Zealand, Great Britain, and the United States. The major goal of this undertaking was the recovery and analysis of sediment core, which was expected to provide a first East Antarctic record of the Early Cenozoic hothouse to icehouse climatic transition. This goal was not attained. Nevertheless, over the three seasons, a 1500 m long composite section was recovered, including a predominantly Early Oligocene to Early Miocene (34—17 Ma) glaciomarine succession. It was analyzed in terms of sediment physical properties, paleontology, tectonic structures and geophysics. This multidisciplinary investigation allowed detailed reconstruction of a significant portion of local environmental history, spanning a period of highly variable environmental conditions strongly affected by local glacier advance and retreat across the Victoria Land Basin margin.

Bryozoans were found in upper Cenozoic diamictite debris that crops out at the southwestern tip of Cape Lamb, Vega Island. The diamictite is the youngest deposit on the island and richly composed of foraminifers, brachiopods and scallops. The foraminifera assemblage recovered from the Cape Lamb diamictite and 87 Sr/ 86 Sr isotopic age obtained from the pectinid Adamussium colbecki in the nearby locality of Terrapin indicates a Pleistocene age for this deposit. The main goal of this contribution is to present a bryozoan assemblage of Microporella stenoporta Hayward et Taylor, Hippothoa flagellum Manzoni, Ellisina antarctica (Kluge), Micropora notialis Hayward et Ryland and an indeterminate crisiid constituting the first record of these bryozoan taxa in Cenozoic diamictites of the Antarctic Peninsula.

New echinoid material from the Oligocene Chlamys Ledge Member (uppermost part of the Polonez Cove Formation) on King George Island, West Antarctica, includes the “regular” echinoid Caenopedina aleksandrabitnerae sp. n. and poorly preserved spatangoids, here tentatively identified as members of the genus Abatus . Caenopedina aleksandrabitnerae sp. n. is characterized by fully tuberculate genital plates, which sets it apart from most other species in the genus, by the uneven periproctal margin which indicates that periproctal plates were incorporated into the apical disc, and by moderately wide interambulacral plates with a height/width ratio of 1:3. Among the modern Caenopedina species it is closest to the Australian and New Zealand representatives, which is in contrast to previous reviews of Cenozoic Antarctic echinoid faunas that suggested limited relationship to the Australasian region. This is the first record of Caenopedina from Antarctica; it considerably extends its historical distribution to the south.

Echinoids represent an important component of the Cenozoic marine benthic communities. Their diversity in the Mediterranean area is reviewed within the Late Miocene–Recent, a period of remarkable paleogeographic and paleo- climate changes. Of the 37 genera that lived during the Late Miocene, only Holaster, Pliolampas, and Trachyaster did not survive the Messinian Mediterranean salinity crisis (MSC), indicating that this event was not as drastic as for other marine groups. The presence of Brissopsis within the uppermost Messinian testifies to the existence of fully marine conditions at least towards the end of the MSC. Severe drops in the echinoid diversity, involving the loss of 40% of the Pliocene genera, occurred during the Piacenzian, likely because of the onset of the Northern Hemisphere glaciation. Most of the echinoid extinctions correlate with the crisis of the Mediterranean bivalve assemblage recorded at about 3 Ma. The Early Pleistocene progressive cooling caused the disappearance of further thermophilous shallow-water genera (Clypeaster, Schizechinus, Echinolampas) and allowed the entrance of temperate taxa ( Paracentrotus lividus, Placentinechinus davolii and Sphaerechinus granularis) from the Atlantic. Some deep-water taxa ( Histocidaris sicula, Stirechinus scillae, Cidaris margaritifera), whose Recent relatives are currently restricted to tropical areas, are not found in the area after the Calabrian possibly because of the disappearance of the psychrosphere. The extant Mediterranean echinoid fauna mainly derives from the Late Miocene fauna, reduced after several climatic changes by about 43% at the genus level. The recent increase of the sea surface temperatures allowed the entrance of the Lessepsian Diadema seto sum and confined the deep-water species of Holanthus to the coldest areas of the basin, making this genus endangered.

Micropaleontological and palynological samples from three Cenozoic diamictites at Cape Lamb, Vega Island, James Ross Basin were analysed. Fossiliferous samples yielded reworked and autochthonous a ssemblages of Mesozoic calcareous nannofossils, impoverished Cretaceous foraminifer a together with Neogene species, as well as Late Cretaceous dinoflagellate cysts, pollen, spores and abundant Cenozoic microforaminiferal linings. The recovered nannoflora indicates Early Cretaceous (Hauterivian–Albian) and Late Cretaceous (Santonian–Early Campanian) ages, suggesting an in tensive reworking of marine sediments. The presence of the Early Cretaceous species Nannoconus circularis Deres et Acheriteguy in the diamictite represents its first record for the James Ross Basin. The scarce foraminiferal fauna includes Pullenia jarvisi Cushman, which indicates reworking from lower Maastrichtian–lower Paleocene sediments, and also the Neogene autochthonous Trochammina sp. aff. T. intermedia. The inner−organic layer observed inside this specimen appears to be identical to microforaminiferal linings recovered from the same sample. Palynomorphs found in the studied samples suggest erosion from the underlying Snow Hill Island and the López de Berto − dano Formation beds (upper Campanian–upper M aastrichtian). These recovered assemblages indicate either different periods of deposition or reworking from diverse sources during Cenozoic glaciation, originating in James Ross Island and the Antarctic Peninsula with the influence of local sediment sources.