slushball Earth
E779331
Slushball Earth is a hypothesis proposing that during ancient global glaciations, Earth’s oceans were mostly ice-covered but retained thin equatorial melt zones of open or slushy water, allowing some climate and biological activity to persist.
Observed surface forms (1)
| Surface form | Occurrences |
|---|---|
| Slushball Earth | 0 |
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
Earth system science concept
ⓘ
alternative to Snowball Earth hypothesis ⓘ paleoclimate hypothesis ⓘ |
| addressesQuestion |
how life survived extreme Neoproterozoic glaciations
ⓘ
how sedimentary and geochemical records formed under near-global ice cover ⓘ |
| assumes |
equatorial insolation sufficient to maintain melt zones
ⓘ
high planetary albedo due to extensive ice cover ⓘ |
| challengedBy | interpretations favoring fully ice-covered Snowball Earth conditions ⓘ |
| concernsTimePeriod |
Neoproterozoic Era
NERFINISHED
ⓘ
approximately 720 to 635 million years ago ⓘ |
| contrastsWith | Snowball Earth NERFINISHED ⓘ |
| describes | Earth surface conditions during some Cryogenian ice ages ⓘ |
| differsFrom | Snowball Earth by allowing open or slushy equatorial oceans ⓘ |
| field |
Earth system modeling
ⓘ
geology ⓘ paleobiology ⓘ paleoclimatology ⓘ |
| hasComponent |
equatorial open-water or slushy-water belts
ⓘ
thick sea ice at mid to high latitudes ⓘ |
| hasConsequence |
allows continued biogeochemical cycling under ice-dominated conditions
ⓘ
permits refugia for marine organisms near the equator ⓘ |
| hasMainIdea |
Earth’s oceans were mostly ice-covered during certain ancient glaciations
NERFINISHED
ⓘ
some climate and biological activity could continue despite extensive ice cover ⓘ thin equatorial melt zones of open or slushy water persisted ⓘ |
| implies |
ongoing hydrological cycle under extensive ice cover
ⓘ
reduced but nonzero global biological productivity ⓘ some exchange of gases between ocean and atmosphere during glaciations ⓘ |
| proposes |
equatorial regions with seasonally or permanently reduced ice thickness
ⓘ
global sea ice cover that is not completely solid and continuous ⓘ |
| relatedConcept |
Snowball Earth
NERFINISHED
ⓘ
evolution of early complex life ⓘ global glaciation ⓘ paleogeography of Neoproterozoic continents ⓘ sea-ice dynamics ⓘ |
| relatesTo |
Cryogenian Period
NERFINISHED
ⓘ
Marinoan glaciation NERFINISHED ⓘ Neoproterozoic global glaciations ⓘ Sturtian glaciation ⓘ |
| status | actively debated in the scientific literature ⓘ |
| supportedBy |
climate modeling studies that produce partially ice-covered oceans
ⓘ
fossil evidence of photosynthetic and heterotrophic life during glacial intervals ⓘ geological evidence inconsistent with a completely frozen ocean ⓘ |
| usedToExplain |
paleontological evidence of active marine ecosystems during glacial intervals
ⓘ
persistence of marine photosynthesis during global glaciations ⓘ presence of banded iron formations and other chemical sediments during glaciations ⓘ sedimentary evidence for open-water or dynamic sea-ice conditions ⓘ survival and diversification of early eukaryotes during Cryogenian ice ages ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.