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Recent post-750 Ma continental reconstructions constrain models for East African Orogeny formation and also the scattered remnants of ~640 Ma granulites, whose genesis is controversial. One such Neoproterozoic granulite belt is the Schirmacher Oasis in East Antarctica, isolated from the distinctly younger Pan-African orogen to the south in the central...

The relative roles of fluvial versus glacial processes in shaping the landscape of Antarctica have been debated since the expeditions of Robert Scott and Ernest Shackleton in the early years of the 20th century. Here we build a synthesis of Antarctic landscape evolution based on the geomorphology of passive continental...

Yucca Flat is a topographic and structural basin in the northeastern part of the Nevada Test Site (NTS) in Nye County, Nevada, that has been the site of numerous underground nuclear tests; many of these tests occurred within the young alluvial basin-fill deposits. The migration of radionuclides to the Paleozoic...

The Transantarctic Mountains demarcate the boundary between the highly extended lithosphere of the West Antarctic Rift System and the Proterozoic East Antarctic Craton. Although the last stage of relief development was in the Eocene, the TAM retain peak elevations in excess of 4500 m. This combination of old age and high relief...

Because of the paucity of exposed rock, the direct physical record of Antarctic Cenozoic glacial history has become known only recently and then largely from offshore shelf basins through seismic surveys and drilling. The number of holes on the continental shelf has been small and largely confined to three areas...

The Antarctic Seismic Data Library System for Cooperative Research (SDLS) has served for the past 16 years under the auspices of the Antarctic Treaty (ATCM Recommendation XVI-12) as a role model for collaboration and equitable sharing of Antarctic multichannel seismic reflection (MCS) data for geoscience studies. During this period, collaboration...

Site NBP0602A-9, drilled during the SHALDRIL II cruise of the RV/IB Nathaniel B. Palmer, includes two holes located in the northern James Ross Basin in the western Weddell Sea, very close to the eastern margin of the Antarctic Peninsula. Sediment from both holes consists of very dark grey, pebbly, sandy...

When 12 countries established scientific stations in Antarctica for the 1957-58 (IGY), the Cold War was at its height, seven countries had made claims in Antarctica, and the Antarctic Treaty was in the future. The only major field project of the U.S. IGY Antarctic program was series of oversnow traverses,...

The Ellsworth Mountains, first mapped under the leadership of Campbell Craddock, pose critical geological enigmas, solved and unsolved. The isolation of the mountains, their abrupt structural terminations and Paleozoic stratigraphic affinities are explained by rotation from the cratonic margin during Gondwanaland breakup. The mechanism remains obscure. The absence of intense...

The United States Geological Survey (USGS) is working cooperatively with the National Oceanic and Atmospheric Association (NOAA) to interpret the surficial geology in estuaries along the coast of the northeastern United States. The purpose of our present study is to determine the distributions of surficial sediments and sedimentary environments in...

The Hanson Formation of the Central Transantarctic Mountains has yielded a diverse Early Jurassic terrestrial fauna, which includes the nearly complete theropod dinosaur, Cryolophosaurus ellioti, and a fragmentary basal sauropodomorph dinosaur. The Hanson Formation dinosaurs are important for understanding early dinosaur evolution because: 1) they preserve a mosaic of morphological traits that render...

The Antarctic Multibeam Bathymetry and Geophysical Data Synthesis(AMBS) is a web-accessible data resource for marine geoscience research in the Southern Ocean. The primary focusisto preserve and provide public accessto multibeam bathymetry acquired during expeditions of research vesselssupported by the U.S. National Science Foundation. Since itsinception in 2003, our primary goal has been to...

Antarctica has geometric significance for global plate kinematic studies, because it links seafloor spreading systems of the African hemisphere (Indian and Atlantic Oceans) with those of the Pacific. Inferences of plate motions back to 44 Ma, around the onset of rapid spreading south of Australia and formation of a new...

Core JPC17B was collected from the Adélie-Drift, a nearly 300-m thick drift deposit at 140ºE along the Indian Ocean sector of the Antarctic continental shelf. Sediments consist of nearly continuously laminated diatom mud and diatom ooze, with accumulation rates on the order of 20-21 m kyr-1 based on 10 AMS radiocarbon...

Neoproterozoic Rodinia reconstructions associate East Antarctica (EANT) with cratonic Western Australia. By further linking EANT to both Gondwana and Pangea with relative plate circuits, a Synthetic Apparent Polar Wander (SAPW) path for EANT is calculated. This path predicts that EANT was located at tropical to subtropical southerly latitudes from ca....

The highest peak in Antarctica, the Vinson Massif (78º35’S, 85º25’W), is at an elevation of 4892 m (16,046 ft), as determined in 2004. Measurements of the elevation have fluctuated over the years, from its earliest surveyed elevation of 5140 m (16,859 ft), to its present height. Vinson Massif and three...

Paleoenvironmental reconstructions and 40 Ar/ 39 Ar geochronology of seven eroded monogenetic volcanoes near the Hobbs Coast, Marie Byrd Land, West Antarctica provide proxy records of WAIS paleo-ice-levels in Miocene-Pliocene times. Interpretations, based on lithofacies analysis, indicate whether the volcanoes erupted below, near, or above the level of the ice sheet. Our interpretations...

Late Cenozoic lavas and associated hyaloclastite breccias of the Adare volcanics (Hallett volcanic province) in Robertson Bay, North Victoria Land rest unconformably on Paleozoic greywackes. Abundant hyaloclastite breccias are confined to a paleovalley; their primary geological features, and the stable isotope ratios of secondary minerals, are consistent with eruption in...

Volcanic sills and dikes inferred from seismic reflection profiles and geophysical studies of the Ross Sea are thought to be related to the rift basins in the region, and their emplacement to be coeval with extension. However, lack of precise geochronology in the Terror Rift of the Ross Sea region...

Discussion of continental drift around Antarctica began nearly 100 years ago. While the Gondwana connections of Antarctica to Africa and Australia have been well defined for decades, the relative pre-drift positions of the Antarctic Peninsula and Patagonia continue to be subjects of controversy. Certainly older figures, which showed a paleo-position...

Eighteen plagioclase 40Ar/39Ar and 7 whole rock K/Ar ages suggest that dikes in the South Shetland Islands (Antarctic Peninsula) are of Paleocene to Eocene age. The oldest dikes are exposed on Hurd Peninsula (Livingston Island) and do not yield 40Ar/39Ar plateaux. Our best estimates suggest dike intrusion at about the Cretaceous/Paleogene boundary. An...