Perils of petrotectonic modeling

A view from southern Sonora, Mexico

Christy Till, Phillip B. Gans, Frank J. Spera, Ian MacMillan, Karen D. Blair

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

We present major and trace element geochemical data from well-dated Oligocene-Miocene volcanic sections in southern Sonora, Mexico (28°, 110°) that span the transition from subduction to oblique extension in the proto-Gulf of California. The region of northwest Mexico including Sonora experienced this abrupt change in tectonic setting ca. 15-12.5 Ma. Syn- and post-subduction calc-alkaline volcanic rocks erupted in Sonora all have similar major and trace element signatures indicative of a continental arc setting. Post-subduction rocks in Sonora document only a subtle change in the behavior of high field strength, large ion lithophile and rare earth elements and a decrease in pre-eruptive water-content. The protracted geochemical changes in Sonora suggest it took at least 4 m.y. to erase the subduction signature from the sub-arc mantle here. Therefore Sonoran geochemistry is not consistent with the predictions of petrotectonic models and contrasts with central and southern Baja where a rapid and distinct change in the composition of lavas erupted is reported synchronous with the tectonic transition. This study exemplifies the need for caution when interpreting geochemical data for tectonic information in the absence of plate reconstructions.

Original languageEnglish (US)
Pages (from-to)160-168
Number of pages9
JournalJournal of Volcanology and Geothermal Research
Volume186
Issue number3-4
DOIs
StatePublished - Oct 10 2009
Externally publishedYes

Fingerprint

Mexico
Tectonics
subduction
Trace Elements
tectonics
trace elements
modeling
Volcanic rocks
volcanology
Geochemistry
arcs
Gulf of California (Mexico)
signatures
trace element
rocks
Rare earth elements
Heavy ions
continental arc
Water content
alkaline rock

Keywords

  • Gulf of California
  • oblique extension
  • petrotectonic models
  • pre-eruptive water content
  • Sonora, Mexico
  • subduction

ASJC Scopus subject areas

  • Geochemistry and Petrology
  • Geophysics

Cite this

Perils of petrotectonic modeling : A view from southern Sonora, Mexico. / Till, Christy; Gans, Phillip B.; Spera, Frank J.; MacMillan, Ian; Blair, Karen D.

In: Journal of Volcanology and Geothermal Research, Vol. 186, No. 3-4, 10.10.2009, p. 160-168.

Research output: Contribution to journalArticle

Till, Christy ; Gans, Phillip B. ; Spera, Frank J. ; MacMillan, Ian ; Blair, Karen D. / Perils of petrotectonic modeling : A view from southern Sonora, Mexico. In: Journal of Volcanology and Geothermal Research. 2009 ; Vol. 186, No. 3-4. pp. 160-168.
@article{e09bcebc653342c1ae138773299e2e7c,
title = "Perils of petrotectonic modeling: A view from southern Sonora, Mexico",
abstract = "We present major and trace element geochemical data from well-dated Oligocene-Miocene volcanic sections in southern Sonora, Mexico (28°, 110°) that span the transition from subduction to oblique extension in the proto-Gulf of California. The region of northwest Mexico including Sonora experienced this abrupt change in tectonic setting ca. 15-12.5 Ma. Syn- and post-subduction calc-alkaline volcanic rocks erupted in Sonora all have similar major and trace element signatures indicative of a continental arc setting. Post-subduction rocks in Sonora document only a subtle change in the behavior of high field strength, large ion lithophile and rare earth elements and a decrease in pre-eruptive water-content. The protracted geochemical changes in Sonora suggest it took at least 4 m.y. to erase the subduction signature from the sub-arc mantle here. Therefore Sonoran geochemistry is not consistent with the predictions of petrotectonic models and contrasts with central and southern Baja where a rapid and distinct change in the composition of lavas erupted is reported synchronous with the tectonic transition. This study exemplifies the need for caution when interpreting geochemical data for tectonic information in the absence of plate reconstructions.",
keywords = "Gulf of California, oblique extension, petrotectonic models, pre-eruptive water content, Sonora, Mexico, subduction",
author = "Christy Till and Gans, {Phillip B.} and Spera, {Frank J.} and Ian MacMillan and Blair, {Karen D.}",
year = "2009",
month = "10",
day = "10",
doi = "10.1016/j.jvolgeores.2009.06.014",
language = "English (US)",
volume = "186",
pages = "160--168",
journal = "Journal of Volcanology and Geothermal Research",
issn = "0377-0273",
publisher = "Elsevier",
number = "3-4",

}

TY - JOUR

T1 - Perils of petrotectonic modeling

T2 - A view from southern Sonora, Mexico

AU - Till, Christy

AU - Gans, Phillip B.

AU - Spera, Frank J.

AU - MacMillan, Ian

AU - Blair, Karen D.

PY - 2009/10/10

Y1 - 2009/10/10

N2 - We present major and trace element geochemical data from well-dated Oligocene-Miocene volcanic sections in southern Sonora, Mexico (28°, 110°) that span the transition from subduction to oblique extension in the proto-Gulf of California. The region of northwest Mexico including Sonora experienced this abrupt change in tectonic setting ca. 15-12.5 Ma. Syn- and post-subduction calc-alkaline volcanic rocks erupted in Sonora all have similar major and trace element signatures indicative of a continental arc setting. Post-subduction rocks in Sonora document only a subtle change in the behavior of high field strength, large ion lithophile and rare earth elements and a decrease in pre-eruptive water-content. The protracted geochemical changes in Sonora suggest it took at least 4 m.y. to erase the subduction signature from the sub-arc mantle here. Therefore Sonoran geochemistry is not consistent with the predictions of petrotectonic models and contrasts with central and southern Baja where a rapid and distinct change in the composition of lavas erupted is reported synchronous with the tectonic transition. This study exemplifies the need for caution when interpreting geochemical data for tectonic information in the absence of plate reconstructions.

AB - We present major and trace element geochemical data from well-dated Oligocene-Miocene volcanic sections in southern Sonora, Mexico (28°, 110°) that span the transition from subduction to oblique extension in the proto-Gulf of California. The region of northwest Mexico including Sonora experienced this abrupt change in tectonic setting ca. 15-12.5 Ma. Syn- and post-subduction calc-alkaline volcanic rocks erupted in Sonora all have similar major and trace element signatures indicative of a continental arc setting. Post-subduction rocks in Sonora document only a subtle change in the behavior of high field strength, large ion lithophile and rare earth elements and a decrease in pre-eruptive water-content. The protracted geochemical changes in Sonora suggest it took at least 4 m.y. to erase the subduction signature from the sub-arc mantle here. Therefore Sonoran geochemistry is not consistent with the predictions of petrotectonic models and contrasts with central and southern Baja where a rapid and distinct change in the composition of lavas erupted is reported synchronous with the tectonic transition. This study exemplifies the need for caution when interpreting geochemical data for tectonic information in the absence of plate reconstructions.

KW - Gulf of California

KW - oblique extension

KW - petrotectonic models

KW - pre-eruptive water content

KW - Sonora, Mexico

KW - subduction

UR - http://www.scopus.com/inward/record.url?scp=69649102231&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=69649102231&partnerID=8YFLogxK

U2 - 10.1016/j.jvolgeores.2009.06.014

DO - 10.1016/j.jvolgeores.2009.06.014

M3 - Article

VL - 186

SP - 160

EP - 168

JO - Journal of Volcanology and Geothermal Research

JF - Journal of Volcanology and Geothermal Research

SN - 0377-0273

IS - 3-4

ER -