Lewisian complex basement

E154086

Precambrian basement complex gneiss complex high-grade metamorphic terrane

The Lewisian complex basement is an ancient Precambrian assemblage of highly metamorphosed gneisses and related rocks forming part of the geological foundation of northwest Scotland and the Outer Hebrides.

Try in SPARQL Jump to: Surface forms Disambiguation Statements Elicitation Referenced by

All labels observed (5)

Label	Occurrences
Lewisian complex	3
Lewisian Gneiss Complex	2
Lewisian complex basement canonical	1
Lewisian gneiss	1
Lewisian gneiss complex	1

How this entity was disambiguated

This entity first appeared as the object of triple T1343597 — 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: Lewisian complex basement
Context triple: [Dalradian Supergroup, overlies, Lewisian complex basement]

A. Dalradian Supergroup
The Dalradian Supergroup is a thick sequence of late Precambrian to early Paleozoic metamorphic sedimentary and volcanic rocks extensively exposed in the Scottish Highlands and parts of Ireland.
B. Coast Plutonic Complex
The Coast Plutonic Complex is a vast belt of granitic and related intrusive rocks forming the core of the Coast Mountains along the Pacific margin of western North America.
C. Southern Uplands terrane
The Southern Uplands terrane is a geological region in southern Scotland composed mainly of deformed and folded sedimentary rocks, representing an ancient accretionary prism formed during the closure of the Iapetus Ocean.
D. Grampian Terrane
The Grampian Terrane is a major geological block in Scotland characterized by ancient metamorphic and igneous rocks that form much of the Grampian Highlands.
E. Caledonian orogeny
The Caledonian orogeny was a major Paleozoic mountain-building event that formed ranges across what are now Scandinavia, Scotland, Ireland, Greenland, and parts of North America as ancient continents collided.
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: Lewisian complex basement
Target entity description: The Lewisian complex basement is an ancient Precambrian assemblage of highly metamorphosed gneisses and related rocks forming part of the geological foundation of northwest Scotland and the Outer Hebrides.

A. Dalradian Supergroup
The Dalradian Supergroup is a thick sequence of late Precambrian to early Paleozoic metamorphic sedimentary and volcanic rocks extensively exposed in the Scottish Highlands and parts of Ireland.
B. Coast Plutonic Complex
The Coast Plutonic Complex is a vast belt of granitic and related intrusive rocks forming the core of the Coast Mountains along the Pacific margin of western North America.
C. Southern Uplands terrane
The Southern Uplands terrane is a geological region in southern Scotland composed mainly of deformed and folded sedimentary rocks, representing an ancient accretionary prism formed during the closure of the Iapetus Ocean.
D. Grampian Terrane
The Grampian Terrane is a major geological block in Scotland characterized by ancient metamorphic and igneous rocks that form much of the Grampian Highlands.
E. Caledonian orogeny
The Caledonian orogeny was a major Paleozoic mountain-building event that formed ranges across what are now Scandinavia, Scotland, Ireland, Greenland, and parts of North America as ancient continents collided.
F. None of above. chosen

Statements (48)

Predicate	Object
instanceOf	Precambrian basement complex ⓘ gneiss complex ⓘ high-grade metamorphic terrane ⓘ
composedOf	amphibolite-facies gneiss ⓘ granulite-facies gneiss ⓘ mafic dykes ⓘ metasedimentary rocks ⓘ metavolcanic rocks ⓘ
composedPrimarilyOf	gneiss ⓘ
contains	Scourie dykes ⓘ granite intrusions ⓘ migmatites ⓘ shear zones ⓘ
correlatesWith	Nagssugtoqidian and Ketilidian belts of Greenland ⓘ linked to: Greenland Shield
country	Scotland ⓘ
exposedIn	Assynt ⓘ Harris ⓘ Lewis ⓘ Scourie ⓘ
formsBasementTo	Northwest Highlands ⓘ Outer Hebrides ⓘ
formsPartOf	Laurentian continental margin ⓘ linked to: North American continental margin
geologicalAge	Archaean ⓘ Palaeoproterozoic ⓘ
hasKeyLocality	Assynt, Sutherland ⓘ linked to: Assynt Lewis and Harris, Outer Hebrides ⓘ linked to: Lewis and Harris Scourie, Sutherland ⓘ linked to: Scourie Ullapool area ⓘ linked to: Ullapool
hasMetamorphicGrade	amphibolite facies ⓘ granulite facies ⓘ
lithology	banded tonalitic to granodioritic gneiss ⓘ
locatedIn	Outer Hebrides ⓘ northwest Scotland ⓘ
maximumAgeMa	ca. 1700 ⓘ
minimumAgeMa	ca. 3000 ⓘ
namedAfter	Isle of Lewis ⓘ
overlainUnconformablyBy	Cambrian sedimentary rocks ⓘ Torridonian Supergroup ⓘ
partOf	Caledonian foreland ⓘ linked to: Caledonian fault system North Atlantic Craton ⓘ
region	Scottish Highlands ⓘ
researchUse	study of Precambrian tectonics and metamorphism ⓘ
significance	records early crustal evolution of the North Atlantic region ⓘ
structuralStyle	complexly folded and faulted gneiss terrane ⓘ
tectonicHistory	multiple deformation phases ⓘ multiple high-grade metamorphic events ⓘ
underlies	Moine Supergroup ⓘ Torridonian Sandstone ⓘ

How these facts were elicited