File:North america basement rocks.png

From Wikipedia, the free encyclopedia
Jump to: navigation, search
North_america_basement_rocks.png(484 × 429 pixels, file size: 13 KB, MIME type: image/png)

North American cratons and basement rocks.

As radiometric ages were determined for the shield-like rocks on the continents which were either exposed at the surface, underlay the flat rocks, or were within the interior of the mountain belts, patterns of age intervals were determined. These old rocks have been called the "basement". This has been interpreted to mean that the continents had somehow grown by development of rock assemblages with these characteristic age parameters. The expanding continental nuclei are part of the "craton" which consist of both exposed and buried basement rocks.

Source[edit]

Public domain This image is in the public domain because it only contains materials that originally came from the United States Geological Survey, an agency of the United States Department of the Interior. For more information, see the official USGS copyright policy.

български | català | čeština | Deutsch | English | español | eesti | suomi | فارسی | français | galego | italiano | 한국어 | македонски | മലയാളം | Nederlands | polski | português | русский | Türkçe | 中文 | 中文(简体)‎ | +/−

USGS logo green.svg

http://rst.gsfc.nasa.gov/Sect2/14strprv.jpg or http://instruct.uwo.ca/earth-sci/300b-001/14strprv.gif

English Wikipedia, original upload 22 April 2005 by Berkut

History[edit]

Originally uploaded by User:SEWilco as Image:North america basement rocks.jpg. Replaced when this better version found.

derivative works[edit]

Derivative works of this file: North america and scandinavia basement rocks.png

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current15:47, 16 September 2005Thumbnail for version as of 15:47, 16 September 2005484 × 429 (13 KB)SaperaudNorth American cratons and basement rocks. As radiometric ages were determined for the shield-like rocks on the continents which were either exposed at the surface, underlay the flat rocks, or were within the interior of the mountain belts, patte

Global file usage