Snowball Earth glaciations
E219023
Snowball Earth glaciations were extreme global-scale ice ages in the Precambrian when ice sheets may have covered most or all of Earth’s surface for millions of years.
All labels observed (8)
| Label | Occurrences |
|---|---|
| Cryogenian glaciations | 2 |
| Neoproterozoic Snowball Earth episodes | 1 |
| Neoproterozoic glaciations | 1 |
| Snowball Earth | 1 |
| Snowball Earth episodes | 1 |
| Snowball Earth glaciations canonical | 1 |
| Snowball Earth hypothesis | 1 |
| hard Snowball Earth | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T1966316 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
Target entity: Snowball Earth glaciations Context triple: [Precambrian Supereon, includesEvent, Snowball Earth glaciations]
-
A.
Cenozoic glaciations
Cenozoic glaciations are a series of major ice age cycles during the Cenozoic Era that saw extensive growth and retreat of continental ice sheets, profoundly shaping Earth’s climate and landscapes.
-
B.
Eocene–Oligocene climate transition
The Eocene–Oligocene climate transition was a major global cooling event around 34 million years ago that marked the shift from a greenhouse to an icehouse Earth, including the formation of large Antarctic ice sheets.
-
C.
Milankovitch cycles
Milankovitch cycles are long-term variations in Earth’s orbit and axial tilt that drive natural climate fluctuations, including the timing of ice ages.
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D.
Younger Dryas cold event
The Younger Dryas cold event was a brief, abrupt return to near-glacial conditions about 12,900–11,700 years ago that interrupted the general warming trend at the end of the last Ice Age.
-
E.
Northern Hemisphere ice sheets
Northern Hemisphere ice sheets are vast continental glaciers that repeatedly expanded and retreated over North America and Eurasia, profoundly shaping global climate, sea levels, and landscapes during the Quaternary.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
Target entity: Snowball Earth glaciations Target entity description: Snowball Earth glaciations were extreme global-scale ice ages in the Precambrian when ice sheets may have covered most or all of Earth’s surface for millions of years.
-
A.
Cenozoic glaciations
Cenozoic glaciations are a series of major ice age cycles during the Cenozoic Era that saw extensive growth and retreat of continental ice sheets, profoundly shaping Earth’s climate and landscapes.
-
B.
Eocene–Oligocene climate transition
The Eocene–Oligocene climate transition was a major global cooling event around 34 million years ago that marked the shift from a greenhouse to an icehouse Earth, including the formation of large Antarctic ice sheets.
-
C.
Milankovitch cycles
Milankovitch cycles are long-term variations in Earth’s orbit and axial tilt that drive natural climate fluctuations, including the timing of ice ages.
-
D.
Younger Dryas cold event
The Younger Dryas cold event was a brief, abrupt return to near-glacial conditions about 12,900–11,700 years ago that interrupted the general warming trend at the end of the last Ice Age.
-
E.
Northern Hemisphere ice sheets
Northern Hemisphere ice sheets are vast continental glaciers that repeatedly expanded and retreated over North America and Eurasia, profoundly shaping global climate, sea levels, and landscapes during the Quaternary.
- F. None of above. chosen
Statements (60)
| Predicate | Object |
|---|---|
| instanceOf |
Neoproterozoic glaciation
ⓘ
global glaciation ⓘ hypothesized climate state ⓘ paleoclimatic event ⓘ |
| cause |
changes in solar luminosity
ⓘ
continental breakup and configuration ⓘ drawdown of atmospheric carbon dioxide ⓘ enhanced silicate weathering ⓘ ice–albedo positive feedback ⓘ possible methane collapse in the atmosphere ⓘ |
| controversialAspect |
exact trigger mechanisms
ⓘ
extent of sea-ice cover ⓘ number and duration of individual glaciations ⓘ survival habitats for photosynthetic life ⓘ |
| duration | millions of years ⓘ |
| effect |
changes in ocean chemistry
ⓘ
perturbation of global carbon cycle ⓘ possible increase in nutrient flux to oceans ⓘ possible oxygenation events in oceans and atmosphere ⓘ possible stimulation of early animal evolution ⓘ rapid deposition of cap carbonates ⓘ strong greenhouse conditions during deglaciation ⓘ |
| endTime | approximately 635 million years ago ⓘ |
| evidence |
cap carbonate sequences
ⓘ
carbon isotope anomalies ⓘ dropstones in marine sediments ⓘ low-latitude glacial tillites ⓘ paleomagnetic indicators of tropical glaciation ⓘ stratigraphic correlation of glacial units worldwide ⓘ |
| followedBy |
Cambrian explosion
ⓘ
Ediacaran Period ⓘ Ediacaran biota diversification ⓘ |
| hasHypothesisVariant |
Snowball Earth glaciations
self-linksurface differs
ⓘ
surface form:
hard Snowball Earth
slushball Earth ⓘ |
| hasPart |
Gaskiers glaciation
ⓘ
Marinoan glaciation ⓘ Sturtian glaciation ⓘ |
| mainFeature |
cap carbonates overlying glacial sediments
ⓘ
equatorward expansion of ice ⓘ global-scale ice sheets ⓘ large carbon isotope excursions ⓘ possible complete ocean ice cover ⓘ possible ocean anoxia ⓘ sea-ice covered oceans ⓘ strong ice–albedo feedback ⓘ suppressed hydrological cycle ⓘ very low surface temperatures ⓘ widespread glacial deposits at low paleolatitudes ⓘ |
| popularizedBy |
Daniel P. Schrag
ⓘ
Paul F. Hoffman ⓘ |
| proposedBy |
Mikhail Budyko
ⓘ
W. Brian Harland ⓘ |
| startTime | approximately 720 million years ago ⓘ |
| studiedBy |
geochemistry
ⓘ
geology ⓘ paleoclimatology ⓘ paleomagnetism ⓘ |
| temporalLocation |
Cryogenian Period
ⓘ
Neoproterozoic Era ⓘ
surface form:
Neoproterozoic Eon
Precambrian Supereon ⓘ
surface form:
Precambrian
|
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Subject: Snowball Earth glaciations Description of subject: Snowball Earth glaciations were extreme global-scale ice ages in the Precambrian when ice sheets may have covered most or all of Earth’s surface for millions of years.
Referenced by (9)
Full triples — surface form annotated when it differs from this entity's canonical label.