Paleoproterozoic Era
E44484
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.
All labels observed (5)
| Label | Occurrences |
|---|---|
| Paleoproterozoic Era canonical | 12 |
| Paleoproterozoic | 4 |
| Paleoproterozoic Eon | 2 |
| Paleoproterozoic eon | 2 |
| Paleoproterozoic era | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T335901 — 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: Paleoproterozoic Era Context triple: [Proterozoic Eon, subdivision, Paleoproterozoic Era]
-
A.
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.
-
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.
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.
-
D.
Paleozoic Era
The Paleozoic Era was an ancient geologic time interval, spanning roughly 541 to 252 million years ago, marked by the emergence and diversification of complex life in the seas and on land and the assembly of major continental landmasses.
-
E.
Phanerozoic Eon
The Phanerozoic Eon is the current and most recent major division of Earth's history, marked by abundant fossil evidence and the evolution and diversification of complex life forms, including plants, animals, and eventually humans.
- 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: Paleoproterozoic Era Target entity description: 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.
-
A.
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.
-
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.
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.
-
D.
Paleozoic Era
The Paleozoic Era was an ancient geologic time interval, spanning roughly 541 to 252 million years ago, marked by the emergence and diversification of complex life in the seas and on land and the assembly of major continental landmasses.
-
E.
Phanerozoic Eon
The Phanerozoic Eon is the current and most recent major division of Earth's history, marked by abundant fossil evidence and the evolution and diversification of complex life forms, including plants, animals, and eventually humans.
- F. None of above. chosen
Statements (50)
| Predicate | Object |
|---|---|
| instanceOf |
geologic era
ⓘ
subdivision of the Proterozoic Eon ⓘ |
| associatedWithLife |
cyanobacterial mats
ⓘ
early eukaryote fossils (possible) ⓘ prokaryotic life ⓘ stromatolite abundance ⓘ |
| containsEvent |
Great Oxidation Event
ⓘ
Huronian glaciation ⓘ Lomagundi–Jatuli carbon isotope excursion ⓘ major orogenic events on several cratons ⓘ |
| containsSubdivision |
Orosirian Period
ⓘ
Rhyacian Period ⓘ Siderian Period ⓘ Statherian Period ⓘ |
| duration | about 900 million years ⓘ |
| endTime | approximately 1.6 billion years ago ⓘ |
| fieldOfStudy |
geology
ⓘ
paleobiology ⓘ paleoclimatology ⓘ |
| follows | Archean Eon ⓘ |
| hasConsequence |
change in ocean chemistry
ⓘ
cooling of global climate ⓘ drawdown of atmospheric methane ⓘ possible trigger of Paleoproterozoic glaciations ⓘ widespread oxidation of iron in oceans ⓘ |
| hasFeature |
abundant banded iron formations in marine sediments
ⓘ
decline of banded iron formations toward its end ⓘ formation of red beds ⓘ oxidation of surface environments ⓘ rise of atmospheric oxygen above trace levels ⓘ sulfur mass-independent fractionation decline ⓘ |
| hasGeologicalRecord |
extensive metamorphic belts
ⓘ
large igneous provinces ⓘ rocks preserved on multiple cratons worldwide ⓘ |
| hasImpact |
establishment of modern-style biosphere–geosphere interactions
ⓘ
long-term habitability of Earth ⓘ |
| hasKeyFeature | first long-lived continental cratons ⓘ |
| hasKeyProcess |
biological production of oxygen by cyanobacteria
ⓘ
development of plate tectonic style similar to modern ⓘ global-scale orogeny ⓘ growth of continental crust ⓘ intense weathering of continental surfaces ⓘ large-scale glaciations ⓘ oxygenation of Earth’s atmosphere ⓘ stabilization of continental cratons ⓘ widespread formation of banded iron formations ⓘ |
| namedAfter | Greek words for "ancient" and "earlier life" ⓘ |
| partOf | Proterozoic Eon ⓘ |
| precedes | Mesoproterozoic Era ⓘ |
| startTime | approximately 2.5 billion years ago ⓘ |
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: Paleoproterozoic Era Description of subject: 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.
Referenced by (21)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Paleoproterozoic
subject surface form:
Columbia
this entity surface form:
Paleoproterozoic eon
subject surface form:
Nuna
this entity surface form:
Paleoproterozoic eon
this entity surface form:
Paleoproterozoic era
this entity surface form:
Paleoproterozoic
this entity surface form:
Paleoproterozoic Eon
this entity surface form:
Paleoproterozoic Eon
this entity surface form:
Paleoproterozoic
this entity surface form:
Paleoproterozoic