Snowball Earth termination by destabilization of equatorial permafrost methane clathrate

  title={Snowball Earth termination by destabilization of equatorial permafrost methane clathrate},
  author={Martin Kennedy and David D. Mrofka and Christopher von der Borch},
The start of the Ediacaran period is defined by one of the most severe climate change events recorded in Earth history—the recovery from the Marinoan ‘snowball’ ice age, ∼635 Myr ago (ref. 1). Marinoan glacial-marine deposits occur at equatorial palaeolatitudes, and are sharply overlain by a thin interval of carbonate that preserves marine carbon and sulphur isotopic excursions of about -5 and +15 parts per thousand, respectively; these deposits are thought to record widespread oceanic… 

A hydrothermal origin for isotopically anomalous cap dolostone cements from south China

It is proposed that the capacity to form highly 13C-depleted seep carbonates was limited in the Precambrian period by low sulphate concentrations in sea water, and although clathrate destabilization may or may not have had a role in the exit from the ‘snowball’ state, it would not have left extreme carbon isotope signals in cap dolostones.

Sedimentary challenge to Snowball Earth

Evidence from the magnetic field fossilized in sedimentary rocks suggests that, more than 600 million years ago, ice occupied tropical latitudes. A popular explanation for these findings, the

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

Paleosols and weathering leading up to Snowball Earth in central Australia

  • G. Retallack
  • Environmental Science, Geography
    Australian Journal of Earth Sciences
  • 2021
Abstract The Cryogenian Period (717–635 Ma), or ‘Snowball Earth’, was an unusually cool period of Earth history when glaciers extended to low latitudes. Past ideas on causes of this widespread

Revealing the climate of snowball Earth from Δ17O systematics of hydrothermal rocks

A novel approach to reconstruct the 18O/16O composition of ancient meteoric waters using the triple oxygen isotopic composition (17O/ 16O and 18O-16O) of hydrothermally altered rocks of Proterozoic rocks is presented, demonstrating how 17O/15O measurements provide information beyond traditional 18O /16O measurements, even though all fractionation processes are purely mass dependent.



Stable isotopic evidence for methane seeps in Neoproterozoic postglacial cap carbonates

Carbon isotopic and petrographic data from a Neoproterozoic postglacial cap carbonate in south China are reported that provide direct evidence for methane-influenced processes during deglaciation, lending strong support to the hypothesis that methane hydrate destabilization contributed to the enigmatic cap carbonates deposition and strongly negative carbon isotopic anomalies following Neopropriaterozoic ice ages.

Are Proterozoic cap carbonates and isotopic excursions a record of gas hydrate destabilization following Earth's coldest intervals?

Regionally persistent, thin intervals of carbonate rock directly and ubiquitously overlie Proterozoic glacial deposits on almost every continent, and are commonly referred to as cap carbonates. Their

Extreme winds and waves in the aftermath of a Neoproterozoic glaciation

Sediments deposited during this sea level rise contain remarkable structures that are interpreted as giant wave ripples, and it is proposed that these extraordinary wind and wave conditions were characteristic of the climatic transit and provide observational targets for atmospheric circulation models.

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

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

Dissociation of oceanic methane hydrate as a cause of the carbon isotope excursion at the end of the Paleocene

Isotopic records across the “Latest Paleocene Thermal Maximum“ (LPTM) indicate that bottom water temperature increased by more than 4°C during a brief time interval (<104 years) of the latest

Carbonate Deposition, Climate Stability, and Neoproterozoic Ice Ages

Neoproterozoic ice ages of near-global extent and multimillion-year duration and the formation of distinctive sedimentary (cap) carbonates can be understood in terms of the greater sensitivity of the Precambrian carbon cycle to the loss of shallow-water environments and CO2-climate feedback on ice-sheet growth.

Binge/purge oscillations of the Laurentide Ice Sheet as a cause of the North Atlantic's Heinrich events

Ice-rafted debris in sediment cores from the North Atlantic suggests that the Laurentide ice sheet (LIS) periodically disgorged icebergs in brief but violent episodes which occurred approximately

Role of methane clathrates in past and future climates

Methane clathrates are stable at depths greater than about 200 m in permafrost regions and in ocean sediments at water depths greater than about 250 m, provided bottom waters are sufficiently cold.