Portal:Physics/Selected picture/July 2013

From Wikipedia, the free encyclopedia

The age of the Earth is 4.54 ± 0.05 billion years (4.54 × 109 years ± 1%).[1][2][3] This age is based on evidence from radiometric age dating of meteorite material and is consistent with the ages of the oldest-known terrestrial and lunar samples. Following the scientific revolution and the development of radiometric age dating, measurements of lead in uranium-rich minerals showed that some were in excess of a billion years old.[4]

Earth as seen from Apollo 17

Studies of strata, the layering of rocks and earth, gave naturalists an appreciation that Earth may have been through many changes during its existence. These layers often contained fossilized remains of unknown creatures, leading some to interpret a progression of organisms from layer to layer

  1. ^ "Age of the Earth". U.S. Geological Survey. 1997. Archived from the original on 23 December 2005. Retrieved 2006-01-10.
  2. ^ Dalrymple, G. Brent (2001). "The age of the Earth in the twentieth century: a problem (mostly) solved". Special Publications, Geological Society of London. 190 (1): 205–221. Bibcode:2001GSLSP.190..205D. doi:10.1144/GSL.SP.2001.190.01.14.
  3. ^ Manhesa, Gérard; Allègre, Claude J.; Dupréa, Bernard & Hamelin, Bruno (1980). "Lead isotope study of basic-ultrabasic layered complexes: Speculations about the age of the earth and primitive mantle characteristics". Earth and Planetary Science Letters. 47 (3): 370–382. Bibcode:1980E&PSL..47..370M. doi:10.1016/0012-821X(80)90024-2.[verification needed]
  4. ^ Boltwood, B. B. (1907). "On the ultimate disintegration products of the radio-active elements. Part II. The disintegration products of uranium". American Journal of Science. 23 (134): 77–88. doi:10.2475/ajs.s4-23.134.78.
    For the abstract, see: Chemical Abstracts Service, American Chemical Society (1907). Chemical Abstracts. New York, London: American Chemical Society. p. 817. Retrieved 2008-12-19.