U-Pb zircon geochronology of Neoproterozoic-Paleozoic sandstones and Paleozoic plutonic rocks in the Central Andes (21°S-26°S)

Jesse C. Einhorn, George E Gehrels, Antoine Vernon, Peter G Decelles

Research output: Chapter in Book/Report/Conference proceedingChapter

7 Citations (Scopus)

Abstract

The crystalline basement of the Central Andes between 21°S and 26°S consists of a variety of Neoproterozoic-Paleozoic arc-type and basinal assemblages. We characterize these assemblages through analysis of U-Th-Pb ages of zircons sampled from 16 different plutonic suites and from 21 different sandstones in northern Argentina and Chile. The ages of igneous zircons show that magmatism occurred in three main phases: ca. 550 Ma (late Neoproterozoic); 490-464 Ma (Late Cambrian to Middle Ordovician); and 318-264 Ma (late Carboniferous-Late Permian). Detrital zircon ages are mainly 600-450 Ma from Paleozoic strata all across the orogen, reflecting derivation primarily from local Neoproterozoic, Cambrian, and Ordovician magmatic constructs. These relations suggest that crystalline basement in this portion of the Andes was assembled within a broad extensional convergent margin system during early Paleozoic time. Because similar arc and basinal assemblages characterize much of the Terra Australis orogen, it is not possible to constrain the degree of tectonic mobility within this convergent system.

Original languageEnglish (US)
Title of host publicationMemoir of the Geological Society of America
PublisherGeological Society of America
Pages115-124
Number of pages10
Volume212
ISBN (Print)9780813712123
DOIs
StatePublished - 2015

Publication series

NameMemoir of the Geological Society of America
Volume212
ISSN (Print)00721069

Fingerprint

plutonic rock
geochronology
zircon
Paleozoic
sandstone
Ordovician
convergent margin
magmatism
Permian
tectonics

ASJC Scopus subject areas

  • Geology

Cite this

Einhorn, J. C., Gehrels, G. E., Vernon, A., & Decelles, P. G. (2015). U-Pb zircon geochronology of Neoproterozoic-Paleozoic sandstones and Paleozoic plutonic rocks in the Central Andes (21°S-26°S). In Memoir of the Geological Society of America (Vol. 212, pp. 115-124). (Memoir of the Geological Society of America; Vol. 212). Geological Society of America. https://doi.org/10.1130/2015.1212(06)

U-Pb zircon geochronology of Neoproterozoic-Paleozoic sandstones and Paleozoic plutonic rocks in the Central Andes (21°S-26°S). / Einhorn, Jesse C.; Gehrels, George E; Vernon, Antoine; Decelles, Peter G.

Memoir of the Geological Society of America. Vol. 212 Geological Society of America, 2015. p. 115-124 (Memoir of the Geological Society of America; Vol. 212).

Research output: Chapter in Book/Report/Conference proceedingChapter

Einhorn, JC, Gehrels, GE, Vernon, A & Decelles, PG 2015, U-Pb zircon geochronology of Neoproterozoic-Paleozoic sandstones and Paleozoic plutonic rocks in the Central Andes (21°S-26°S). in Memoir of the Geological Society of America. vol. 212, Memoir of the Geological Society of America, vol. 212, Geological Society of America, pp. 115-124. https://doi.org/10.1130/2015.1212(06)
Einhorn JC, Gehrels GE, Vernon A, Decelles PG. U-Pb zircon geochronology of Neoproterozoic-Paleozoic sandstones and Paleozoic plutonic rocks in the Central Andes (21°S-26°S). In Memoir of the Geological Society of America. Vol. 212. Geological Society of America. 2015. p. 115-124. (Memoir of the Geological Society of America). https://doi.org/10.1130/2015.1212(06)
Einhorn, Jesse C. ; Gehrels, George E ; Vernon, Antoine ; Decelles, Peter G. / U-Pb zircon geochronology of Neoproterozoic-Paleozoic sandstones and Paleozoic plutonic rocks in the Central Andes (21°S-26°S). Memoir of the Geological Society of America. Vol. 212 Geological Society of America, 2015. pp. 115-124 (Memoir of the Geological Society of America).
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