Fox Hills Formation
E364205
The Fox Hills Formation is a Late Cretaceous geologic unit in the Western Interior of North America, known for its marine to marginal-marine sandstones that record the final retreat of the Western Interior Seaway.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Fox Hills Formation canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T3502378 — 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: Fox Hills Formation Context triple: [Hell Creek Formation, overlies, Fox Hills Formation]
-
A.
Cloverly Formation
The Cloverly Formation is an Early Cretaceous geologic formation in the western United States known for its dinosaur fossils and fluvial sedimentary deposits.
-
B.
Claron Formation
The Claron Formation is a geologic rock unit of colorful limestones and mudstones best known for forming the striking hoodoos and cliffs of Bryce Canyon and other parts of the Paunsaugunt Plateau in southern Utah.
-
C.
Summerville Formation
The Summerville Formation is a Late Jurassic sedimentary rock unit in the western United States, characterized by thin-bedded mudstones and sandstones deposited in tidal flat and coastal environments.
-
D.
Holston Formation
The Holston Formation is a geologic unit in eastern Tennessee renowned for its high-quality crystalline limestone commonly marketed as Tennessee marble and widely used in prominent architectural projects.
-
E.
Areyonga Formation
The Areyonga Formation is a geological rock unit within central Australia's Amadeus Basin, known for its sedimentary sequences that record Proterozoic environmental and tectonic history.
- 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: Fox Hills Formation Target entity description: The Fox Hills Formation is a Late Cretaceous geologic unit in the Western Interior of North America, known for its marine to marginal-marine sandstones that record the final retreat of the Western Interior Seaway.
-
A.
Cloverly Formation
The Cloverly Formation is an Early Cretaceous geologic formation in the western United States known for its dinosaur fossils and fluvial sedimentary deposits.
-
B.
Claron Formation
The Claron Formation is a geologic rock unit of colorful limestones and mudstones best known for forming the striking hoodoos and cliffs of Bryce Canyon and other parts of the Paunsaugunt Plateau in southern Utah.
-
C.
Summerville Formation
The Summerville Formation is a Late Jurassic sedimentary rock unit in the western United States, characterized by thin-bedded mudstones and sandstones deposited in tidal flat and coastal environments.
-
D.
Holston Formation
The Holston Formation is a geologic unit in eastern Tennessee renowned for its high-quality crystalline limestone commonly marketed as Tennessee marble and widely used in prominent architectural projects.
-
E.
Areyonga Formation
The Areyonga Formation is a geological rock unit within central Australia's Amadeus Basin, known for its sedimentary sequences that record Proterozoic environmental and tectonic history.
- F. None of above. chosen
Statements (49)
| Predicate | Object |
|---|---|
| instanceOf |
Late Cretaceous formation
ⓘ
geologic formation ⓘ stratigraphic unit ⓘ |
| chronostratigraphicPosition | Maastrichtian ⓘ |
| contains |
ammonite fossils
ⓘ
bivalve fossils ⓘ marine invertebrate fossils ⓘ plant fossils ⓘ trace fossils ⓘ vertebrate fossils ⓘ |
| depositionalSetting |
barrier-island complex
ⓘ
nearshore marine ⓘ regressive shoreline system ⓘ |
| economicImportance |
groundwater aquifer in some regions
ⓘ
hydrocarbon reservoir in some basins ⓘ |
| environmentOfDeposition |
deltaic
ⓘ
marginal-marine ⓘ marine ⓘ shoreface ⓘ |
| exposedIn |
Colorado
ⓘ
Montana ⓘ North Dakota ⓘ South Dakota ⓘ Wyoming ⓘ |
| geologicAge | Late Cretaceous ⓘ |
| hasStratigraphicThickness | commonly tens to several hundreds of meters ⓘ |
| lithology |
sandstone
ⓘ
shale ⓘ siltstone ⓘ |
| locatedIn |
Canada
ⓘ
North America ⓘ United States ⓘ
linked to:
United States of America
|
| namedFor | Fox Hills, South Dakota ⓘ |
| overlies | Pierre Shale ⓘ |
| paleogeographicSignificance |
marks transition from marine to continental deposition in Western Interior
ⓘ
records regression of Western Interior Seaway ⓘ |
| partOf | Western Interior Basin ⓘ |
| records | final retreat of the Western Interior Seaway ⓘ |
| researchUse | study of Cretaceous–Paleogene transition environments ⓘ |
| stratigraphicGroup |
Colorado Group
ⓘ
Montana Group ⓘ varies regionally ⓘ |
| underlies |
Frenchman Formation
ⓘ
Hell Creek Formation ⓘ Lance Formation ⓘ Laramie Formation ⓘ Medicine Hat Formation ⓘ Scollard Formation ⓘ Williston Basin Paleocene units ⓘ
linked to:
Williston Basin
|
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: Fox Hills Formation Description of subject: The Fox Hills Formation is a Late Cretaceous geologic unit in the Western Interior of North America, known for its marine to marginal-marine sandstones that record the final retreat of the Western Interior Seaway.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.