ملف:North america terrain 2003.jpg

The North America Tapestry of Time and Terrain (1:8,000,000 scale) is a product of the United States Geological Survey in the I-map series (I-2781). This map was prepared in collaboration with the Geological Survey of Canada and the Mexican Consejo Recursos de Minerales.

This cartographic tapestry is woven from a geologic map and a shaded relief image. This digital combination reveals the geologic history of North America through the interrelation of rock type, topography and time. Regional surface processes as well as continent-scale tectonic events are exposed in the three dimensions of space and the fourth dimension, geologic time. The large map shows the varying age of bedrock underlying North America, while four smaller maps show the distribution of four principal types of rock: sedimentary, volcanic, plutonic and metamorphic.

 Related images

Four maps show the North American distribution of four principal types of rock: sedimentary, volcanic, plutonic and metamorphic.

• North america rock metamorphic.jpg

  Metamorphic rock

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  Plutonic rock

• North america rock sedimentary.jpg

  Sedimentary rock

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  Volcanic rock

There are separate images of the main map, time scale, and rock type maps.

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  North American terrain

• North america terrain 2003 time scale.jpg

  Time scale

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  North American rock types

 Source

This image is a work of a United States Geological Survey employee, taken or made during the course of the person's official duties. As a work of the United States Government, the image is in the public domain. For more information, see the USGS copyright policy.

Home: http://pubs.usgs.gov/imap/i2781/

Image: http://pubs.usgs.gov/imap/i2781/i2781_c_low.pdf 144 dpi, encoded to 72 dpi JPEG, compressed slightly to fit within Wikipedia 2MB limit.

Source: English Wikipedia, original upload 15 April 2005 by SEWilco