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The published latest Palaeocene to Early–Middle Eocene age limits of the Sabrina microfloras, offshore Aurora Subglacial Basin, East Antarctica, largely depend on 1970s age-range data for fossil pollen and spore species in the continental margin basins of southern Australia. This paper uses updated biostratigraphical data from southern Australia, including the basins closest to the Aurora Basin throughout the Late Cretaceous and Paleogene, to propose that the age of the terrestrial component of the Sabrina microfloras is Campanian to Maastrichtian, not Paleogene. However, the revised age limits do not preclude these microfloras being redeposited more or less intact during the development and expansion of ice-sheets on East Antarctica, i.e. most probably during the late Paleogene based on other evidence from East Antarctica. [ABSTRACT FROM AUTHOR]

Anderson Pond in eastern Tennessee is one of only a handful of sites in the interior southeastern US where researchers have developed pollen records that extend to the last full glacial period. Pollen data from the site have been widely used in regional syntheses and models of past vegetation and climate. Previous researchers either constructed age models that assumed continuous sedimentation from the Late Pleistocene to the present, and plotted pollen data by radiocarbon or calibrated ages (1976 core), or recognized the likelihood of hiatuses in the postglacial sediments, and plotted pollen data by depth (2007 cores). We present an improved chronology for the 1976 core based on prior delineation and dating of two hiatuses, and on new age modeling using AMS dates on macrofossils from cores collected in 2007. This new age model allows us to plot pollen and microscopic charcoal by age for the entirety of the record, and more accurately represents site history. Plotting pollen and charcoal assemblages by age using our new chronology highlights the long intervals of time that are missing from the postglacial record at Anderson Pond, while improving our ability to make use of proxy data from the fragmented sediments of this classic pollen site. [ABSTRACT FROM AUTHOR]

We show the first conclusive evidence thatMelitasphaeridium choanophorum, a dinoflagellate cyst species until recently considered extinct, is still living in the northern Gulf of Mexico. This suggests the Gulf of Mexico may have acted as a refugium for some warm-water dinoflagellates during past glaciations.Melitasphaeridium choanophorumcan be considered a living fossil because cysts with cell contents were found among 15 of the 39 surface sediment samples analyzed from the northern Gulf of Mexico, and from five of 12 samples from a dated core (1962–1997).Melitasphaeridium choanophorumcomprises a minor component of the total dinoflagellate cyst assemblages, with a maximum of 1.4% or 15 cysts g−1. It was found in surface sediments with overlying sea-surface temperatures of 16.6 to 31.2 °C (winter and summer), and summer sea-surface salinities of 21.0 to 31.7 psu. The relationship ofM. choanophorumwith modern sea-surface conditions can be used to infer past oceanographic conditions. [ABSTRACT FROM AUTHOR]

Palynological analyses of 12 samples from the Cape Melville Formation, which crops out on easternmost King George Island, Antarctica, provide new information on the type of vegetation that covered the South Shetland Islands during the early Miocene Melville Glaciation, c. 23–21 Ma. The assemblage recovered was mostly characterised byin situalgae such as leiospheres along with acanthomorph acritarchs, both glacial indicators. The sparsein situterrestrial palynomorph assemblage included tundra-indicative moss sporesCoptosporasp., rare podocarp conifer and various angiosperm pollen. The latter includes pollen of several species ofNothofagidites, plus rare Asteraceae, Caryophyllaceae (Colobanthus-type) andChenopodipollis.The majority of the palynomorphs recovered are interpreted as reworked, denoting glacial scouring and redeposition from various sites in the Antarctic Peninsula and the South Shetland Islands. These reworked palynomorphs are of Permian to Paleogene age. This reworked component provides insight into the potential sources of reworking, and is consistent with multiple cycles of glacial advances to the Melville Peninsula at the time of deposition. The penecontemporaneous palynomorphs recovered provide new data on the climatic regime and glacial intensification during the early Miocene on King George Island. [ABSTRACT FROM AUTHOR]

A palynological analysis was undertaken on 16 samples from seven piston cores collected along two offshore transects near Seymour and James Ross Islands. Diverse assemblages of reworked marine microplankton (including organic-walled dinoflagellate cysts, cymatiosphaerids, leiospheres, and other acritarchs) and terrestrial palynomorphs (including pollen and spores) were recovered from glacio-marine sediments of late Pleistocene age. Among the reworked taxa, four species belonging to the acritarch genus Palaeostomocystis Deflandre 1937 comprise up to 17% of all palynomorphs. Highest abundances were recorded from sites close to the coast. The potential use of Palaeostomocystis as a proxy for early ice-sheet development on the Antarctic margins is evaluated in light of earlier studies. This evaluation suggests that the high abundances of Palaeostomocystis on the Antarctic Peninsula reflect neritic-type environments (shallow waters, bay-like areas, or marginal seas) and sub-polar to polar conditions as exist in the Bering Sea, Greenland margins, and other sub- arctic to arctic areas today. [ABSTRACT FROM AUTHOR]

The establishment of the Converrucosisporites confluens Oppel Zone in the Canning Basin of Australia in cored intervals from the Calytrix No. 1 Borehole was considered to be an advance in Gondwana Carboniferous-Permian palynostratigraphy. This was because the zone is associated with a marine fauna that suggests a correlation with the standard Russian Early Permian stages. Moreover the index species has a wide occurrence in Gondwana outside Australia, for example Antarctica, Argentina, Brazil, India, Oman, Saudi Arabia, and Uruguay. The zone was originally considered middle to late Asselian in age, but this was later revised to latest Asselian to Early Sakmarian. Converrucosisporites confluens is reported here from the Ganigobis Shale Member of Namibia in a well-preserved and diverse assemblage including four of the fourteen specified accessory taxa for the Converrucosisporites confluens Oppel Zone. Ash layer lib of the Ganigobis Shale Member is radiometrically dated as 302.0 ±3.0 Ma (i.e. Pennsylvanian; Gzhelian or Kasimovian) thus the Converrucosisporites confluens Oppel Zone may range earlier than previously thought. Preliminary study of the range top of Converrucosisporites confluens in Argentina and Uruguay suggests that it ranges younger there than in Western Australia with the possibility that the Converrucosisporites confluens Oppel Zone may also be younger than previously thought. [ABSTRACT FROM AUTHOR]