Results 51 to 60 of about 2,147 (148)
A Decrease to Low Carbonate Clumped Isotope Temperatures in Cryogenian Strata
AGU Advances, 2020 Preglacial and synglacial low‐latitude carbonate sediments of the Elbobreen Formation, NE Svalbard, preserve facies changes associated with low‐latitude glacial advance in Cryogenian “Snowball Earth” episodes (717–635 Ma).
T. J. Mackey +3 more
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Eos, Transactions American Geophysical Union, 2006 Many scientists have been considering the idea that the Earth may have completely frozen over sometime in the past. Kirschvink [1992] proposed that a runaway ice‐albedo effect on continents amassed in low latitudes caused the descent into a global freeze.
openaire +1 more source
Influence of Orbital Forcing on the Snowball Earth Deglaciation
Geophysical Research LettersNeoproterozoic snowball Earth events lasted for multiple million years, experiencing many orbital cycles. Here we investigate whether the deglaciation of these events would be triggered more easily at certain orbital configurations than others, by using ...
Jiacheng Wu, Yonggang Liu
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Weak tides during Cryogenian glaciations
Nature Communications, 2020 How and why the ‘Snowball Earth’ occurred during the Cryogenian period is debated. Here, the authors show that the cryogenian ocean hosted diminished tidal amplitudes and associated energy dissipation rates, reaching 10-50% of today’s rates thus perhaps ...
J. A. Mattias Green +4 more
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MineralogiaThe diagenetic processes exhibited by the Neoproterozoic diamictites from Murchisonfjorden (Nordaustlandet, NE Svalbard) are presented. Diamictite samples from the Cryogene Polarisbreen Group - the Petrovbreen Member of the Elbobreen Formation and the ...
Bal Szczepan +6 more
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Deep‐Time Paleoclimate Proxies
AGU Advances, 2020 Pre‐Cenozoic climate (>66 million years ago) has been reconstructed with climate sensitive sedimentary deposits. However, sedimentary records are inherently local and can be affected by topography and oceanic and atmospheric currents.
Francis A. Macdonald
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Snowball Bistability Vanishes at Moderate Orbital Eccentricity
The Planetary Science JournalSnowball episodes are associated with increases in atmospheric oxygen and the complexity of life on Earth, and they may be essential for the development of complex life on exoplanets. Sustained, stable Snowball episodes require a Snowball bifurcation and
Xuan Ji, Dorian S. Abbot
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Nordicum-MediterraneumThis article extends our time horizon back 720 million years for a deep-historical examination of the interplay of geological, biological, and climatic dynamics to inform our understanding of Arctic globalization across the eons.
Barry Zellen
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Natural SciencesDuring the late 20th and early 21st century three conceptual revolutions reordered our understanding of the history of the Earth: The spread of plate tectonic theory from the 1960s onward which brought geology the first meaningful theory for building ...
Douglas H. Erwin
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A slippery slope for Cryogenian diamictites?
The Depositional Record, 2019 The Death Valley region has previously been claimed to preserve the sedimentary records of both the Sturtian and Marinoan snowball Earth events within the Kingston Peak Formation, which outcrops in a number of disconnected mountain ranges.
Daniel Paul Le Heron, Thomas M. Vandyk
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