Estimating Duration and Intensity of Neoproterozoic Snowball Glaciations from Ir Anomalies

  title={Estimating Duration and Intensity of Neoproterozoic Snowball Glaciations from Ir Anomalies},
  author={Bernd Bodiselitsch and Christian Koeberl and Sharad Master and Wolf Uwe Reimold},
  pages={239 - 242}
The Neoproterozoic glaciations supposedly ended in a supergreenhouse environment, which led to rapid melting of the ice cover and precipitation of the so-called cap carbonates. If Earth was covered with ice, then extraterrestrial material would have accumulated on and within the ice and precipitated during rapid melting at the end of the glaciation. We found iridium (Ir) anomalies at the base of cap carbonates in three drill cores from the Eastern Congo craton. Our data confirm the presence of… 

A Review of the Neoproterozoic Global Glaciations and a Biotic Cause of Them

  • Juan Casado
  • Geography, Environmental Science
    Earth Systems and Environment
  • 2021
In the Neoproterozoic Era, the Earth experienced two broad intervals of global glaciation, commonly known as Snowball Earth. There was also a rapid diversification of life, with the evolution of most

Neoproterozoic loess and limits to snowball Earth

  • G. Retallack
  • Geography, Environmental Science
    Journal of the Geological Society
  • 2011
Abstract: Neoproterozoic tillites overlain by limestones and dolostones (cap carbonates) have been interpreted as evidence of abrupt climate change from glaciers to tropical seas on the assumption

On Cryogenian ( Neoproterozoic ) icesheet dynamics and the limitations of the glacial sedimentary record

The snowball earth hypothesis is a unified theory accounting for the global distribution of Cryogenian (roughly 720 to 635 Ma) glacial and glacial marine deposits, their global synchroneity

Testing the snowball Earth hypothesis for the Ediacaran

Ediacaran Siberia was at tropical paleolatitudes when the glacigenic strata of the Goloustnaya Formation (Baikal Group, Siberia) were deposited at sea level. The presence of such deposits (at

Fast or slow melting of the Marinoan snowball Earth? The cap dolostone record

Neoproterozoic glaciation in the Earth System

The Neoproterozoic contains severe glacial intervals (750–580 Ma) including two extending to low palaeomagnetic latitudes. Paucity of radiometric dates indicates the need for chronostratigraphic

Neoproterozoic loess and limits to snowball Earth service Email alerting

Neoproterozoic tillites overlain by limestones and dolostones (cap carbonates) have been interpreted as evidence of abrupt climate change from glaciers to tropical seas on the assumption that cap

Toward the snowball earth deglaciation…

The current state of knowledge suggests that the Neoproterozoic snowball Earth is far from deglaciation even at 0.2 bars of CO2. Since understanding the termination of the fully ice-covered state is

Climate of the Neoproterozoic

The Neoproterozoic is a time of transition between the ancient microbial world and the Phanerozoic, marked by a resumption of extreme carbon isotope fluctuations and glaciation after a billion-year



A neoproterozoic snowball earth

Negative carbon isotope anomalies in carbonate rocks bracketing Neoproterozoic glacial deposits in Namibia, combined with estimates of thermal subsidence history, suggest that biological productivity

Neoproterozoic ‘snowball Earth’ simulations with a coupled climate/ice-sheet model

Computer simulations of this unusual climate stage with a coupled climate/ice-sheet model and a general circulation model result in an equatorial belt of open water that may have provided a refugium for multicellular animals.

CO2 levels required for deglaciation of a “near‐snowball” Earth

Geologic evidence suggests that in the Late Neoproterozoic (∼600 Ma) almost all land masses were glaciated, with sea‐level glaciation existing even at the equator. A recent modeling study has shown

Susceptibility of the early Earth to irreversible glaciation caused by carbon dioxide clouds

The authors' simulations of the early Earth, incorporating the possible formation of highly reflective CO2 clouds, suggest that the Earth might not be habitable today had it not been warm during the first part of its history.

Paleomagnetic polarity reversals in Marinoan (ca. 600 Ma) glacial deposits of Australia: Implications for the duration of low-latitude glaciation in Neoproterozoic time

A paleomagnetic investigation of Marinoan glacial and preglacial deposits in Australia was conducted to reevaluate Australia’s paleogeographic position at the time of glaciation (ca. 610‐575 Ma). The

Accretion rates of meteorites and cosmic dust in the Early Ordovician.

Osmium isotope and iridium analyses of whole-rock limestone indicate a coeval enhancement of one order of magnitude in the influx rate of cosmic dust.

Late Precambrian Dolomites, Vendian Glaciation, and Synchroneity of Vendian Glaciations

  • J. Roberts
  • Geology, Environmental Science
    The Journal of Geology
  • 1976
The late Precambrian Vendian Glaciation may have been triggered by a worldwide fall of temperature following the locking up of carbon dioxide in Upper Riphean Dolomites. In this "anti-greenhouse"

Biostratigraphic and Geochronologic Constraints on Early Animal Evolution

Two distinct evolutionary pulses, represented by the Vendian Ediacaran fauna and Cambrian small shelly faunas, are generally thought to characterize the emergence of macroscopic animals at the end of

Stratigraphy, sedimentology, and isotopic geochemistry of Australian Neoproterozoic postglacial cap dolostones; deglaciation, delta 13 C excursions, and carbonate precipitation

ABSTRACT Thin (d13C excursions in the geologic record, they are interpreted to record a brief postglacial anomaly in ocean chemistry. In Australia, the Marinoan (Varanger equivalent 600 Ma) cap