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LITHOEN

Tectonic plate

North American Plate

A major tectonic plate carrying most of North America, bounded on its west by the San Andreas transform system and on its east by the Mid-Atlantic Ridge.

World map showing twenty-four plate outlines as thin dark lines over a pale coastline, with heavier red plate-boundary curves over them, subduction segments dashed, and thirteen hatched purple regions marking zones of distributed deformation.
Twenty-four tectonic plates as outlined in model PB2002 (Bird, 2003), with the boundary curves Lithoen holds for them and the thirteen regions the model calls orogens. Every line here is a model boundary rather than a mapped geological contact: the model is a compilation from published sources at varying scales, its author states that accuracy never equals precision, and boundary class changes along a boundary — so only the segments the source labels subduction are shown as such. Outlines are generalised for display at a recorded tolerance. Areas near the poles are severely exaggerated by the projection, which is stated on the figure.

Figure by Lithoen. Plate model PB2002 from Bird (2003), doi:10.1029/2001GC000252; GIS conversion by Hugo Ahlenius, Nordpil, ODC-By 1.0. Made with Natural Earth. Underlying data remain under their own licences. · LITHOEN-ORIGINAL · Derivative: Generated from published Lithoen spatial records by scripts/generate-maps.ts; no coordinate was edited by hand. Features spanning ±180° are split for rendering only; the stored geometry is unchanged.

Classification

plate class
major

How this is mapped

3 published representations of where North American Plate is. Each is one interpretation, by one identified source, at one scale — not the shape of the thing itself.

  • Tectonic model geometry

    Polygon · 395 positionspreferred for publication

    Geometry that exists because a model defines it — a rigid-plate outline, a zone where a model declares itself inapplicable. It is a property of the model, and changes when the model is revised. It is present-day geometry from a present-day model; a palaeogeographic reconstruction is a different thing and Lithoen does not hold one.

    The North American Plate as outlined in model PB2002 (Bird, 2003). This is the model’s boundary, not a mapped geological contact: it is where a rigid-plate model puts the edge of a plate, and Bird’s own documentation states that coordinates are given to a precision of about 60 m while "accuracy never equals precision". Where deformation is distributed rather than confined to a line, the model marks the region as an orogen and the outline there is a convenience.

    Boundary certainty
    InterpretedThe boundary was placed by a geologist reading evidence: mapping, geophysics, geochronology, structure. It is reproducible from that evidence and it is an interpretation of it. Most geological boundaries are this.
    Status of this geometry
    modelledThe status of the geometry, which need not match the status of what the entity’s claims assert.
    Dataset
    PB2002 plates, boundaries and orogens as GeoJSON (fraxen/tectonicplates)Plate model PB2002 from Bird (2003), doi:10.1029/2001GC000252; GIS conversion by Hugo Ahlenius, Nordpil, ODC-By 1.0.

    What was done to this geometry

    • By Lithoen — Douglas–Peucker, 1065 positions to 395
    • By Lithoen — Coordinates rounded to 4 decimal places, about 11 m of longitude at the equator.
    • Before it reached Lithoen — Bird (2003) digitised the boundary curves from published sources at varying scales; the model is a compilation, not a single survey.
    • Before it reached Lithoen — The GIS conversion (Ahlenius, ODC-By 1.0) split segments spanning the -180/180 meridian and moved them, as its README states. Four plates therefore arrive as multi-part geometries.

  • Boundary

    MultiLineString · 127 positions

    A line delimiting or separating things — a plate boundary, a suture, a mapped contact. A boundary is not an extent: it says where the edge runs, not what lies on either side.

    North American–Pacific boundary as drawn in model PB2002 (Bird, 2003), from source segments NA-PA, PA-NA. This is the boundary that carries the San Andreas transform system in California and the Aleutian subduction zone in the north — one plate pair, two entirely different kinds of motion along different parts of its length. The model applies no class to these segments. Bird states that a single class cannot always be specified for an entire boundary curve, or even for an entire segment, because the class changes with local changes in azimuth — so Lithoen classifies no further than the source does. The segments of this plate pair are split across two records because the source labels part of it subduction and part of it unclassified; merging them would have asserted one class for the whole. Digitised by: DeMets and Wilson, 1997; Mueller et al. [1987]; by Peter Bird, 1999.

    Boundary certainty
    InterpretedThe boundary was placed by a geologist reading evidence: mapping, geophysics, geochronology, structure. It is reproducible from that evidence and it is an interpretation of it. Most geological boundaries are this.
    Status of this geometry
    modelledThe status of the geometry, which need not match the status of what the entity’s claims assert.
    Dataset
    PB2002 plates, boundaries and orogens as GeoJSON (fraxen/tectonicplates)Plate model PB2002 from Bird (2003), doi:10.1029/2001GC000252; GIS conversion by Hugo Ahlenius, Nordpil, ODC-By 1.0.

    What was done to this geometry

    • By Lithoen — 4 source features carrying the same identifier were combined into one multi-part geometry; no coordinate was altered by the combination.
    • By Lithoen — Coordinates rounded to 4 decimal places, about 11 m of longitude at the equator.
    • Before it reached Lithoen — Bird (2003) compiled these curves from published sources at varying scales, crediting each segment to its own source; those credits are carried in the caption of every record.
    • Before it reached Lithoen — The GIS conversion (Ahlenius, ODC-By 1.0) split segments spanning the -180/180 meridian and moved them, as its README states.

  • Boundary

    MultiLineString · 106 positions

    A line delimiting or separating things — a plate boundary, a suture, a mapped contact. A boundary is not an extent: it says where the edge runs, not what lies on either side.

    North American–Pacific boundary as drawn in model PB2002 (Bird, 2003), from source segments NA/PA. This is the boundary that carries the San Andreas transform system in California and the Aleutian subduction zone in the north — one plate pair, two entirely different kinds of motion along different parts of its length. The model labels these segments as subduction. The segments of this plate pair are split across two records because the source labels part of it subduction and part of it unclassified; merging them would have asserted one class for the whole. Digitised by: by Peter Bird, September 2001.

    Boundary certainty
    InterpretedThe boundary was placed by a geologist reading evidence: mapping, geophysics, geochronology, structure. It is reproducible from that evidence and it is an interpretation of it. Most geological boundaries are this.
    Status of this geometry
    modelledThe status of the geometry, which need not match the status of what the entity’s claims assert.
    Dataset
    PB2002 plates, boundaries and orogens as GeoJSON (fraxen/tectonicplates)Plate model PB2002 from Bird (2003), doi:10.1029/2001GC000252; GIS conversion by Hugo Ahlenius, Nordpil, ODC-By 1.0.

    What was done to this geometry

    • By Lithoen — 3 source features carrying the same identifier were combined into one multi-part geometry; no coordinate was altered by the combination.
    • By Lithoen — Coordinates rounded to 4 decimal places, about 11 m of longitude at the equator.
    • Before it reached Lithoen — Bird (2003) compiled these curves from published sources at varying scales, crediting each segment to its own source; those credits are carried in the caption of every record.
    • Before it reached Lithoen — The GIS conversion (Ahlenius, ODC-By 1.0) split segments spanning the -180/180 meridian and moved them, as its README states.

In the knowledge graph

Record last updated 2026-09-06. Corrections follow the published corrections policy; superseded claims are retained, never silently edited.