Hadean Eon
E219020
The Hadean Eon is the earliest interval of Earth's history, marked by planetary formation, intense bombardment, and a largely molten surface before the emergence of stable crust and oceans.
All labels observed (3)
| Label | Occurrences |
|---|---|
| Hadean Eon canonical | 4 |
| Hadean | 1 |
| Hadean erathem | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T1966274 — 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.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Hadean Eon Context triple: [Precambrian Supereon, includes, Hadean Eon]
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A.
Precambrian Supereon
The Precambrian Supereon is the vast span of Earth's early history before the Phanerozoic, encompassing the Hadean, Archean, and Proterozoic eons during which the planet formed, life first appeared, and early continents and atmospheres developed.
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B.
Archean Eon
The Archean Eon is an ancient geological eon of Earth's history, spanning from about 4.0 to 2.5 billion years ago, characterized by the formation of the first stable continental crust and the earliest known life.
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C.
Proterozoic Eon
The Proterozoic Eon is a major division of Precambrian time, spanning from about 2.5 billion to 541 million years ago, marked by the buildup of atmospheric oxygen, the emergence of complex single-celled and early multicellular life, and the assembly of large continental landmasses.
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D.
Neoproterozoic Era
The Neoproterozoic Era was the final era of the Proterozoic Eon, marked by global “Snowball Earth” glaciations and the emergence of early multicellular life leading up to the Cambrian explosion.
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E.
Paleoproterozoic Era
The Paleoproterozoic Era was an early division of Earth's history marked by the stabilization of continental cratons, widespread banded iron formations, and the Great Oxidation Event that significantly increased atmospheric oxygen.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Hadean Eon Target entity description: The Hadean Eon is the earliest interval of Earth's history, marked by planetary formation, intense bombardment, and a largely molten surface before the emergence of stable crust and oceans.
-
A.
Precambrian Supereon
The Precambrian Supereon is the vast span of Earth's early history before the Phanerozoic, encompassing the Hadean, Archean, and Proterozoic eons during which the planet formed, life first appeared, and early continents and atmospheres developed.
-
B.
Archean Eon
The Archean Eon is an ancient geological eon of Earth's history, spanning from about 4.0 to 2.5 billion years ago, characterized by the formation of the first stable continental crust and the earliest known life.
-
C.
Proterozoic Eon
The Proterozoic Eon is a major division of Precambrian time, spanning from about 2.5 billion to 541 million years ago, marked by the buildup of atmospheric oxygen, the emergence of complex single-celled and early multicellular life, and the assembly of large continental landmasses.
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D.
Neoproterozoic Era
The Neoproterozoic Era was the final era of the Proterozoic Eon, marked by global “Snowball Earth” glaciations and the emergence of early multicellular life leading up to the Cambrian explosion.
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E.
Paleoproterozoic Era
The Paleoproterozoic Era was an early division of Earth's history marked by the stabilization of continental cratons, widespread banded iron formations, and the Great Oxidation Event that significantly increased atmospheric oxygen.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
geologic eon
ⓘ
time interval ⓘ |
| appliesTo | Earth ⓘ |
| associatedWith | zircon crystals older than 4.0 billion years ⓘ |
| atmosphereComposition | likely rich in CO2 water vapor and other volatiles ⓘ |
| boundaryDefinition |
end at about 4.0 Ga before Archean
ⓘ
start at formation of Earth ⓘ |
| characterizedBy |
early atmosphere formation
ⓘ
early hydrosphere formation ⓘ frequent large impacts ⓘ high internal heat flow ⓘ intense meteorite bombardment ⓘ largely molten surface ⓘ planetary accretion ⓘ |
| crustType | early mafic to ultramafic crust ⓘ |
| definedBy | absolute age boundaries rather than rock strata ⓘ |
| duration | about 600 million years ⓘ |
| endTime | about 4.0 billion years ago ⓘ |
| evidenceFrom | detrital zircons from Jack Hills Australia ⓘ |
| follows | formation of the Solar System ⓘ |
| fossilRecord | no confirmed body fossils known ⓘ |
| habitability | potentially allowed transient habitable conditions late in the eon ⓘ |
| hasStatus | informal chronostratigraphic unit in some schemes ⓘ |
| hasUncertain | formal stratigraphic definition ⓘ |
| impactEffects | periodic crustal remelting and atmospheric modification ⓘ |
| includesEvent |
Late Heavy Bombardment era
ⓘ
surface form:
Late Heavy Bombardment (if it occurred)
differentiation of Earth into core mantle and crust ⓘ formation of Earth’s core ⓘ formation of the Moon ⓘ formation of the proto-crust ⓘ possible formation of earliest oceans ⓘ |
| moonFormationHypothesis | giant impact hypothesis ⓘ |
| namedAfter | Hades ⓘ |
| oceanPresence | likely intermittent or early stable oceans late in the eon ⓘ |
| partOf | Precambrian Supereon ⓘ |
| positionInTimeScale | earliest eon of Earth history ⓘ |
| possibleBiologicalEvidence | highly debated isotopic signatures ⓘ |
| precedes | Archean Eon ⓘ |
| startTime | about 4.6 billion years ago ⓘ |
| suggests | liquid water existed on Earth before 4.0 billion years ago ⓘ |
| surfaceEvolution | progressive cooling and crust solidification ⓘ |
| surfaceState | dominated by magma oceans early in the eon ⓘ |
| tectonicRegime | poorly understood and likely different from modern plate tectonics ⓘ |
| temperatureRegime | much hotter than present-day Earth ⓘ |
| usedIn |
geochronology
ⓘ
geology ⓘ planetary science ⓘ |
| volcanism | extensive and widespread ⓘ |
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.
Instruction
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.
Input
Subject: Hadean Eon Description of subject: The Hadean Eon is the earliest interval of Earth's history, marked by planetary formation, intense bombardment, and a largely molten surface before the emergence of stable crust and oceans.
Referenced by (6)
Full triples — surface form annotated when it differs from this entity's canonical label.
subject surface form:
International Chronostratigraphic Chart
this entity surface form:
Hadean
this entity surface form:
Hadean erathem