Misplaced Pages

Overprinting (geology)

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
Geological process that leaves marks altering the marks of an earlier process
In this orthogneiss from the Czech Republic the original igneous rock texture has been overprinted by foliation associated with metamorphism.

Overprinting is a geological process that superimposes a set of characteristics on rock that partially obscure earlier characteristics. Examples include metamorphic overprinting (superimposed metamorphism), in which new structure, texture, or mineral composition is imposed on existing rock. For example, the Tauern window of Alps contains beds that were originally metamorphosed to eclogite but have since been overprinted to the blueschist and then the greenschist facies. Likewise, deformation associated with the Mazatzal orogeny in Arizona and New Mexico, US, was subsequently overprinted by deformation associated with the Picuris orogeny.

Geochemical signatures can also be overprinted when the geochemistry of a geological body is changed by eliminating or modifying the earlier geochemical signature.

References

  1. Yardley, Bruce W. D. (1989). An Introduction to Metamorphic Petrology. Longman Earth Science Series. Harlow, Essex, England: Longman Scientific & Technical. p. 246. ISBN 0-582-30096-7.
  2. Jackson, Julia A., ed. (1997). "metamorphic overprint". Glossary of geology (Fourth ed.). Alexandria, Virginia: American Geological Institute. ISBN 0922152349.
  3. Yardley 1989, pp. 211, 214.
  4. Zhao, Lei; Zhai, Ming-Guo; Nutman, Allen P.; Oh, Chang-Whan; Bennett, Vickie C.; Zhang, Yanbin (July 2020). "Archean basement components and metamorphic overprints of the Rangnim Massif in the northern part of the Korean Peninsula and tectonic implications for the Sino-Korean Craton". Precambrian Research. 344: 105735. doi:10.1016/j.precamres.2020.105735. S2CID 218819425.
  5. Yardley 1989, p. 211.
  6. Mako, Calvin A.; Williams, Michael L.; Karlstrom, Karl E.; Doe, Michael F.; Powicki, David; Holland, Mark E.; Gehrels, George; Pecha, Mark (December 2015). "Polyphase Proterozoic deformation in the Four Peaks area, central Arizona, and relevance for the Mazatzal orogeny". Geosphere. 11 (6): 1975–1995. doi:10.1130/GES01196.1.
  7. Jackson 1997, "overprint ".
  8. Brewer, Timothy S.; Menuge, Julian F. (March 1998). "Metamorphic overprinting of SmNd isotopic systems in volcanic rocks: the Telemark supergroup, southern Norway". Chemical Geology. 145 (1–2): 1–16. doi:10.1016/S0009-2541(97)00114-9.
Category: