Development of a continental forearc: A Cenozoic example from the Central Andes, northern Chile

A J Hartley, G May, G Chong, P Turner, S J Kape, E J Jolley

Research output: Contribution to journalArticle

95 Citations (Scopus)

Abstract

In order to understand the response of a continental forearc to changes in subduction-zone geodynamics, we constructed a high-resolution chronostratigraphic cross section across the Central Andean forearc of northern Chile (21 degrees-24 degrees S), The tectono-stratigraphic development of the forearc differs from established models. No relationship was found between changes in rate of relative plate convergence and amount and style of deformation. Forearc response to continual compression since the Oligocene has been uplift and segmentation into discrete tectonostratigraphic zones. From west to east, these zones are the extensional Coastal Cordillera, the extensional and/or transtensional Central depression, and the transpressional and/or compressional Precordillera-Preandean depression. Each area has recorded almost continuous sedimentation from Oligocene (?Eocene) time to the present day, Accommodation space has been generated by basin-margin uplift rather than active subsidence, We propose a model in which uplift of the leading edge of the South American plate is driven by subcrustal accretion of material removed at the trench by subduction erosion. Uplift and subduction erosion result in the trenchward gravitational collapse of the plate edge. The tectono-stratigraphic complexity exhibited within the Central Andean forearc is likely to be representative of Cordilleran-type margins and would be difficult to recognize in an ancient continental forearc.

Original languageEnglish
Pages (from-to)331-334
Number of pages4
JournalGeology
Volume28
Publication statusPublished - 2000

Keywords

  • Andes
  • northern Chile
  • continental forearc
  • Cenozoic
  • subduction
  • TECTONICS
  • ATACAMA
  • MARGIN
  • BASINS
  • SYSTEM
  • ZONE
  • PERU

Cite this

Hartley, A. J., May, G., Chong, G., Turner, P., Kape, S. J., & Jolley, E. J. (2000). Development of a continental forearc: A Cenozoic example from the Central Andes, northern Chile. Geology, 28, 331-334.

Development of a continental forearc: A Cenozoic example from the Central Andes, northern Chile. / Hartley, A J ; May, G ; Chong, G ; Turner, P ; Kape, S J ; Jolley, E J .

In: Geology, Vol. 28, 2000, p. 331-334.

Research output: Contribution to journalArticle

Hartley, AJ, May, G, Chong, G, Turner, P, Kape, SJ & Jolley, EJ 2000, 'Development of a continental forearc: A Cenozoic example from the Central Andes, northern Chile', Geology, vol. 28, pp. 331-334.
Hartley, A J ; May, G ; Chong, G ; Turner, P ; Kape, S J ; Jolley, E J . / Development of a continental forearc: A Cenozoic example from the Central Andes, northern Chile. In: Geology. 2000 ; Vol. 28. pp. 331-334.
@article{fb08e19920054fbfba208e4e77944e46,
title = "Development of a continental forearc: A Cenozoic example from the Central Andes, northern Chile",
abstract = "In order to understand the response of a continental forearc to changes in subduction-zone geodynamics, we constructed a high-resolution chronostratigraphic cross section across the Central Andean forearc of northern Chile (21 degrees-24 degrees S), The tectono-stratigraphic development of the forearc differs from established models. No relationship was found between changes in rate of relative plate convergence and amount and style of deformation. Forearc response to continual compression since the Oligocene has been uplift and segmentation into discrete tectonostratigraphic zones. From west to east, these zones are the extensional Coastal Cordillera, the extensional and/or transtensional Central depression, and the transpressional and/or compressional Precordillera-Preandean depression. Each area has recorded almost continuous sedimentation from Oligocene (?Eocene) time to the present day, Accommodation space has been generated by basin-margin uplift rather than active subsidence, We propose a model in which uplift of the leading edge of the South American plate is driven by subcrustal accretion of material removed at the trench by subduction erosion. Uplift and subduction erosion result in the trenchward gravitational collapse of the plate edge. The tectono-stratigraphic complexity exhibited within the Central Andean forearc is likely to be representative of Cordilleran-type margins and would be difficult to recognize in an ancient continental forearc.",
keywords = "Andes, northern Chile, continental forearc, Cenozoic, subduction, TECTONICS, ATACAMA, MARGIN, BASINS, SYSTEM, ZONE, PERU",
author = "Hartley, {A J} and G May and G Chong and P Turner and Kape, {S J} and Jolley, {E J}",
year = "2000",
language = "English",
volume = "28",
pages = "331--334",
journal = "Geology",
issn = "0091-7613",
publisher = "GEOLOGICAL SOC AMER, INC",

}

TY - JOUR

T1 - Development of a continental forearc: A Cenozoic example from the Central Andes, northern Chile

AU - Hartley, A J

AU - May, G

AU - Chong, G

AU - Turner, P

AU - Kape, S J

AU - Jolley, E J

PY - 2000

Y1 - 2000

N2 - In order to understand the response of a continental forearc to changes in subduction-zone geodynamics, we constructed a high-resolution chronostratigraphic cross section across the Central Andean forearc of northern Chile (21 degrees-24 degrees S), The tectono-stratigraphic development of the forearc differs from established models. No relationship was found between changes in rate of relative plate convergence and amount and style of deformation. Forearc response to continual compression since the Oligocene has been uplift and segmentation into discrete tectonostratigraphic zones. From west to east, these zones are the extensional Coastal Cordillera, the extensional and/or transtensional Central depression, and the transpressional and/or compressional Precordillera-Preandean depression. Each area has recorded almost continuous sedimentation from Oligocene (?Eocene) time to the present day, Accommodation space has been generated by basin-margin uplift rather than active subsidence, We propose a model in which uplift of the leading edge of the South American plate is driven by subcrustal accretion of material removed at the trench by subduction erosion. Uplift and subduction erosion result in the trenchward gravitational collapse of the plate edge. The tectono-stratigraphic complexity exhibited within the Central Andean forearc is likely to be representative of Cordilleran-type margins and would be difficult to recognize in an ancient continental forearc.

AB - In order to understand the response of a continental forearc to changes in subduction-zone geodynamics, we constructed a high-resolution chronostratigraphic cross section across the Central Andean forearc of northern Chile (21 degrees-24 degrees S), The tectono-stratigraphic development of the forearc differs from established models. No relationship was found between changes in rate of relative plate convergence and amount and style of deformation. Forearc response to continual compression since the Oligocene has been uplift and segmentation into discrete tectonostratigraphic zones. From west to east, these zones are the extensional Coastal Cordillera, the extensional and/or transtensional Central depression, and the transpressional and/or compressional Precordillera-Preandean depression. Each area has recorded almost continuous sedimentation from Oligocene (?Eocene) time to the present day, Accommodation space has been generated by basin-margin uplift rather than active subsidence, We propose a model in which uplift of the leading edge of the South American plate is driven by subcrustal accretion of material removed at the trench by subduction erosion. Uplift and subduction erosion result in the trenchward gravitational collapse of the plate edge. The tectono-stratigraphic complexity exhibited within the Central Andean forearc is likely to be representative of Cordilleran-type margins and would be difficult to recognize in an ancient continental forearc.

KW - Andes

KW - northern Chile

KW - continental forearc

KW - Cenozoic

KW - subduction

KW - TECTONICS

KW - ATACAMA

KW - MARGIN

KW - BASINS

KW - SYSTEM

KW - ZONE

KW - PERU

M3 - Article

VL - 28

SP - 331

EP - 334

JO - Geology

JF - Geology

SN - 0091-7613

ER -