Mafic volcanism on the Puna Plateau, NW Argentina: Implications for lithospheric composition and evolution with an emphasis on lithospheric foundering

Scott T. Drew, Mihai N Ducea, Lindsay M. Schoenbohm

Research output: Contribution to journalArticle

41 Citations (Scopus)

Abstract

Lithospheric foundering has drawn increasing attention as an important contributor to continental plateau formation, especially as a driver for increased elevation, extension, and mafic magmatism. This contribution focuses on the mafic magmatism that led to the creation of monogenetic volcanoes throughout the Puna Plateau of NW Argentina. Lavas from these volcanoes provide a means to evaluate the recent petrotectonic development of the plateau and, in combination with basement intrusive rocks, determine the isotopic composition and long-term evolution of the lithosphere beneath the central Andean back-arc domain. Mafic samples have trace-element concentrations and isotopic values typical of an enriched magma source region. We propose that the mafic magmas originated from an aged, metasomatized subcontinental lithospheric mantle. The lavas have isotopic values nearly identical to those of Early Ordovician Famatinian gabbro and granodiorite. We suggest the most primitive Puna lavas and Famatinian magmas originated from the same subcontinental lithospheric mantle. This implies that at least a thin portion of the subcontinental lithospheric mantle has remained intact beneath NW Argentina for the past ~485 Ma. A comparison to coastal Jurassic igneous rocks and mantle xenoliths from the nearby Salta rift system suggests that the subcontinental lithospheric mantle is chemically decoupled from the depleted mantle to the west and east. This has been the case for hundreds of millions of years despite long-term tectono-magmatic activity along the proto-Andean and Andean margin and within the continental interior. Our data almost certainly rule out large delaminating bodies, suggesting instead partial or piecemeal removal of the lithosphere beneath the Puna Plateau.

Original languageEnglish (US)
Pages (from-to)305-318
Number of pages14
JournalLithosphere
Volume1
Issue number5
DOIs
StatePublished - 2009

Fingerprint

volcanism
plateau
mantle
magmatism
lithosphere
volcano
continental interior
basement rock
gabbro
granodiorite
igneous rock
Ordovician
isotopic composition
Jurassic
magma
trace element

ASJC Scopus subject areas

  • Geology

Cite this

Mafic volcanism on the Puna Plateau, NW Argentina : Implications for lithospheric composition and evolution with an emphasis on lithospheric foundering. / Drew, Scott T.; Ducea, Mihai N; Schoenbohm, Lindsay M.

In: Lithosphere, Vol. 1, No. 5, 2009, p. 305-318.

Research output: Contribution to journalArticle

@article{9e8e2464eccc4da7bc02e1ee6ae55c60,
title = "Mafic volcanism on the Puna Plateau, NW Argentina: Implications for lithospheric composition and evolution with an emphasis on lithospheric foundering",
abstract = "Lithospheric foundering has drawn increasing attention as an important contributor to continental plateau formation, especially as a driver for increased elevation, extension, and mafic magmatism. This contribution focuses on the mafic magmatism that led to the creation of monogenetic volcanoes throughout the Puna Plateau of NW Argentina. Lavas from these volcanoes provide a means to evaluate the recent petrotectonic development of the plateau and, in combination with basement intrusive rocks, determine the isotopic composition and long-term evolution of the lithosphere beneath the central Andean back-arc domain. Mafic samples have trace-element concentrations and isotopic values typical of an enriched magma source region. We propose that the mafic magmas originated from an aged, metasomatized subcontinental lithospheric mantle. The lavas have isotopic values nearly identical to those of Early Ordovician Famatinian gabbro and granodiorite. We suggest the most primitive Puna lavas and Famatinian magmas originated from the same subcontinental lithospheric mantle. This implies that at least a thin portion of the subcontinental lithospheric mantle has remained intact beneath NW Argentina for the past ~485 Ma. A comparison to coastal Jurassic igneous rocks and mantle xenoliths from the nearby Salta rift system suggests that the subcontinental lithospheric mantle is chemically decoupled from the depleted mantle to the west and east. This has been the case for hundreds of millions of years despite long-term tectono-magmatic activity along the proto-Andean and Andean margin and within the continental interior. Our data almost certainly rule out large delaminating bodies, suggesting instead partial or piecemeal removal of the lithosphere beneath the Puna Plateau.",
author = "Drew, {Scott T.} and Ducea, {Mihai N} and Schoenbohm, {Lindsay M.}",
year = "2009",
doi = "10.1130/L54.1",
language = "English (US)",
volume = "1",
pages = "305--318",
journal = "Lithosphere",
issn = "1941-8264",
publisher = "Geological Society of America",
number = "5",

}

TY - JOUR

T1 - Mafic volcanism on the Puna Plateau, NW Argentina

T2 - Implications for lithospheric composition and evolution with an emphasis on lithospheric foundering

AU - Drew, Scott T.

AU - Ducea, Mihai N

AU - Schoenbohm, Lindsay M.

PY - 2009

Y1 - 2009

N2 - Lithospheric foundering has drawn increasing attention as an important contributor to continental plateau formation, especially as a driver for increased elevation, extension, and mafic magmatism. This contribution focuses on the mafic magmatism that led to the creation of monogenetic volcanoes throughout the Puna Plateau of NW Argentina. Lavas from these volcanoes provide a means to evaluate the recent petrotectonic development of the plateau and, in combination with basement intrusive rocks, determine the isotopic composition and long-term evolution of the lithosphere beneath the central Andean back-arc domain. Mafic samples have trace-element concentrations and isotopic values typical of an enriched magma source region. We propose that the mafic magmas originated from an aged, metasomatized subcontinental lithospheric mantle. The lavas have isotopic values nearly identical to those of Early Ordovician Famatinian gabbro and granodiorite. We suggest the most primitive Puna lavas and Famatinian magmas originated from the same subcontinental lithospheric mantle. This implies that at least a thin portion of the subcontinental lithospheric mantle has remained intact beneath NW Argentina for the past ~485 Ma. A comparison to coastal Jurassic igneous rocks and mantle xenoliths from the nearby Salta rift system suggests that the subcontinental lithospheric mantle is chemically decoupled from the depleted mantle to the west and east. This has been the case for hundreds of millions of years despite long-term tectono-magmatic activity along the proto-Andean and Andean margin and within the continental interior. Our data almost certainly rule out large delaminating bodies, suggesting instead partial or piecemeal removal of the lithosphere beneath the Puna Plateau.

AB - Lithospheric foundering has drawn increasing attention as an important contributor to continental plateau formation, especially as a driver for increased elevation, extension, and mafic magmatism. This contribution focuses on the mafic magmatism that led to the creation of monogenetic volcanoes throughout the Puna Plateau of NW Argentina. Lavas from these volcanoes provide a means to evaluate the recent petrotectonic development of the plateau and, in combination with basement intrusive rocks, determine the isotopic composition and long-term evolution of the lithosphere beneath the central Andean back-arc domain. Mafic samples have trace-element concentrations and isotopic values typical of an enriched magma source region. We propose that the mafic magmas originated from an aged, metasomatized subcontinental lithospheric mantle. The lavas have isotopic values nearly identical to those of Early Ordovician Famatinian gabbro and granodiorite. We suggest the most primitive Puna lavas and Famatinian magmas originated from the same subcontinental lithospheric mantle. This implies that at least a thin portion of the subcontinental lithospheric mantle has remained intact beneath NW Argentina for the past ~485 Ma. A comparison to coastal Jurassic igneous rocks and mantle xenoliths from the nearby Salta rift system suggests that the subcontinental lithospheric mantle is chemically decoupled from the depleted mantle to the west and east. This has been the case for hundreds of millions of years despite long-term tectono-magmatic activity along the proto-Andean and Andean margin and within the continental interior. Our data almost certainly rule out large delaminating bodies, suggesting instead partial or piecemeal removal of the lithosphere beneath the Puna Plateau.

UR - http://www.scopus.com/inward/record.url?scp=84988351601&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84988351601&partnerID=8YFLogxK

U2 - 10.1130/L54.1

DO - 10.1130/L54.1

M3 - Article

AN - SCOPUS:84988351601

VL - 1

SP - 305

EP - 318

JO - Lithosphere

JF - Lithosphere

SN - 1941-8264

IS - 5

ER -