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Updated Definition and Correlation of the Lower Fifteenmile Group in the Central and Eastern Ogilvie Mountains
(Yukon Geological Survey, 2012)
Ongoing mapping, chemostratigraphy, geochronology, and stratigraphic analysis of Neoproterozoic successions in the Ogilvie Mountains requires redefinition and correlation of the Fifteenmile Group across the Proterozoic ...
Possible early foraminiferans in post-Sturtian (716-635 Ma) cap carbonates
(Geological Society of America, 2011)
Foraminifera are an ecologically important group of modern heterotrophic amoeboid eukaryotes whose naked and testate ancestors are thought to have evolved ∼1 Ga ago. However, the single-chambered agglutinated tests of these ...
Early Neoproterozoic Basin Formation in Yukon, Canada: Implications for the Make-Up and Break-Up of Rodinia
(Geological Association of Canada, 2012)
Geological mapping and stratigraphic anaylsis of the early Neoproterozoic Fifteenmile Group in the western Ogilvie Mountains of Yukon, Canada, has revealed large lateral facies changes in both carbonate and siliciclastic ...
Uncovering the Neoproterozoic Carbon Cycle
(Nature Publishing Group, 2012)
Interpretations of major climatic and biological events in Earth history are, in large part, derived from the stable carbon isotope records of carbonate rocks and sedimentary organic matter1,2. Neoproterozoic carbonate ...
A Low Temperature Transfer of ALH84001 from Mars to Earth
(American Association for the Advancement of Science (AAAS), 2000)
The ejection of material from Mars is thought to be caused by large impacts that would heat much of the ejecta to high temperatures. Images of the magnetic field of martian meteorite ALH84001 reveal a spatially heterogeneous ...
Yarrabubba - A Large, Deeply Eroded Impact Structure in the Yilgarn Craton, Western Australia
(Elsevier, 2003)
Yarrabubba is a newly discovered impact structure situated within the complex granite^greenstone terrain of the Yilgarn Craton. Shock-metamorphic effects including shatter cones, planar deformation features in quartz grains, ...
Geology of Five Small Australian Impact Craters
(Wiley Blackwell, 2005)
Here we present detailed geological maps and cross-sections of Liverpool, Wolfe Creek, Boxhole, Veevers and Dalgaranga craters. Liverpool crater and Wolfe Creek Meteorite Crater are classic bowlshaped, Barringer-type ...
The Stratigraphic Relationship Between the Shuram Carbon Isotope Excursion, the Oxygenation of Neoproterozoic Oceans, and the First Appearance of the Ediacara Biota and Bilaterian Trace Fossils in Northwestern Canada
(Elsevier BV, 2013)
A mechanistic understanding of relationships between global glaciation, a putative second rise in atmospheric oxygen, the Shuram carbon isotope excursion, and the appearance of Ediacaran-type fossil impressions and ...
Searching for an oxygenation event in the fossiliferous Ediacaran of northwestern Canada
(Elsevier BV, 2013)
Late Neoproterozoic (Ediacaran) strata from northwestern Canada provide a thick and rich sedimentological record, preserving intercalated carbonates and shale extending from the ~ 635 million year old Marinoan glacial ...
A Basin Redox Transect at the Dawn of Animal Life
(Elsevier BV, 2013)
Multiple eukaryotic clades make their first appearance in the fossil record between ~810 and 715 Ma. Molecular clock studies suggest that the origin of animal multicellularity may have been part of this broader eukaryotic ...