Siderian Period
E226913
The Siderian Period is the earliest division of the Paleoproterozoic, marked by widespread banded iron formation deposition and the initial rise of atmospheric oxygen on Earth.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Siderian Period canonical | 3 |
How this entity was disambiguated
This entity first appeared as the object of triple T2029559 — 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: Siderian Period Context triple: [Paleoproterozoic Era, containsSubdivision, Siderian Period]
-
A.
Permian Period
The Permian Period was the final period of the Paleozoic Era, marked by the diversification of reptiles and the largest mass extinction in Earth's history at its close.
-
B.
Triassic
The Triassic was the first period of the Mesozoic Era, marked by the initial diversification of dinosaurs and the recovery of life following the Permian–Triassic mass extinction.
-
C.
Jurassic Period
The Jurassic Period was a major division of the Mesozoic Era characterized by warm climates, the dominance and diversification of dinosaurs, and the early evolution of birds.
-
D.
Devonian Period
The Devonian Period was a division of the Paleozoic Era characterized by the diversification of fish, the first significant colonization of land by plants and early tetrapods, and major reef-building in the oceans.
-
E.
Toarcian
The Toarcian is a stage of the Early Jurassic period characterized by significant marine life diversification and notable oceanic anoxic events.
- 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: Siderian Period Target entity description: The Siderian Period is the earliest division of the Paleoproterozoic, marked by widespread banded iron formation deposition and the initial rise of atmospheric oxygen on Earth.
-
A.
Permian Period
The Permian Period was the final period of the Paleozoic Era, marked by the diversification of reptiles and the largest mass extinction in Earth's history at its close.
-
B.
Triassic
The Triassic was the first period of the Mesozoic Era, marked by the initial diversification of dinosaurs and the recovery of life following the Permian–Triassic mass extinction.
-
C.
Jurassic Period
The Jurassic Period was a major division of the Mesozoic Era characterized by warm climates, the dominance and diversification of dinosaurs, and the early evolution of birds.
-
D.
Devonian Period
The Devonian Period was a division of the Paleozoic Era characterized by the diversification of fish, the first significant colonization of land by plants and early tetrapods, and major reef-building in the oceans.
-
E.
Toarcian
The Toarcian is a stage of the Early Jurassic period characterized by significant marine life diversification and notable oceanic anoxic events.
- F. None of above. chosen
Statements (40)
| Predicate | Object |
|---|---|
| instanceOf |
chronostratigraphic unit
ⓘ
geologic period ⓘ |
| associatedWith | Great Oxidation Event ⓘ |
| atmosphericOxygenTrend | increasing ⓘ |
| biologicalContext | early evolution of oxygen-producing photosynthetic microorganisms ⓘ |
| biosphereImpact | onset of oxygen stress for anaerobic life ⓘ |
| category | Paleoproterozoic geologic period ⓘ |
| characterizedBy |
initial rise of atmospheric oxygen
ⓘ
widespread banded iron formation deposition ⓘ |
| chronologicalRank | period ⓘ |
| climateContext | precedes Paleoproterozoic glaciations ⓘ |
| earthHistoryRole | transition from Archean-style to Proterozoic-style Earth system ⓘ |
| end |
2.3 billion years ago
ⓘ
2300 million years ago ⓘ |
| environmentalChange |
decline in dissolved iron in the oceans
ⓘ
progressive oxygenation of Earth’s surface environments ⓘ |
| era | Paleoproterozoic Era ⓘ |
| followedBy | Rhyacian Period ⓘ |
| follows |
Archean Eon
ⓘ
Neoarchean Era ⓘ |
| geologicEon | Proterozoic Eon ⓘ |
| geologicRecord | preserved mainly in Precambrian shields ⓘ |
| globalSignificance | major transition in Earth surface redox state ⓘ |
| ironCycle | extensive precipitation of iron oxides ⓘ |
| lithostratigraphicExpression | banded iron formations ⓘ |
| lowerBoundaryAge | 2500 Ma ⓘ |
| nameEtymology | derived from Greek "sideros" meaning iron ⓘ |
| notableProcess |
formation of large iron ore deposits
ⓘ
oxidation of dissolved ferrous iron in oceans ⓘ |
| partOf | Paleoproterozoic Era ⓘ |
| positionInEra | earliest period of the Paleoproterozoic ⓘ |
| precededBy | low atmospheric oxygen levels of the Archean ⓘ |
| precedence | first period of the Proterozoic Eon ⓘ |
| start |
2.5 billion years ago
ⓘ
2500 million years ago ⓘ |
| stratigraphicBoundaryDefinition | defined by absolute age rather than a specific stratotype ⓘ |
| timeScale |
Precambrian
ⓘ
Proterozoic Eon ⓘ |
| upperBoundaryAge | 2300 Ma ⓘ |
| usedIn |
International Commission on Stratigraphy
ⓘ
surface form:
International Commission on Stratigraphy time scale
|
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: Siderian Period Description of subject: The Siderian Period is the earliest division of the Paleoproterozoic, marked by widespread banded iron formation deposition and the initial rise of atmospheric oxygen on Earth.
Referenced by (3)
Full triples — surface form annotated when it differs from this entity's canonical label.