Crustal structure across the central Alaska Range: Anatomy of a Mesozoic collisional zone
A first-order process in the growth of continents is the collision and accretion of terranes against continental margins. Collision leads to the formation of a suture zone between the accreted terrane and the former continental margin. New insights on the suturing process are observed from two recei...
Published in: | Geochemistry, Geophysics, Geosystems |
---|---|
Main Authors: | , , |
Format: | Text |
Language: | unknown |
Published: |
Purdue University
2011
|
Subjects: | |
Online Access: | https://docs.lib.purdue.edu/easpubs/10 https://doi.org/10.1029/2011GC003519 https://docs.lib.purdue.edu/context/easpubs/article/1002/viewcontent/Brennan.pdf |
id |
ftpurdueuniv:oai:docs.lib.purdue.edu:easpubs-1002 |
---|---|
record_format |
openpolar |
spelling |
ftpurdueuniv:oai:docs.lib.purdue.edu:easpubs-1002 2023-07-02T03:29:29+02:00 Crustal structure across the central Alaska Range: Anatomy of a Mesozoic collisional zone Brennan, P.R.K. Gilbert, H. Ridgway, K. D. 2011-01-01T08:00:00Z application/pdf https://docs.lib.purdue.edu/easpubs/10 https://doi.org/10.1029/2011GC003519 https://docs.lib.purdue.edu/context/easpubs/article/1002/viewcontent/Brennan.pdf unknown Purdue University https://docs.lib.purdue.edu/easpubs/10 doi:10.1029/2011GC003519 https://docs.lib.purdue.edu/context/easpubs/article/1002/viewcontent/Brennan.pdf Department of Earth, Atmospheric, and Planetary Sciences Faculty Publications receiver functions suture zone Alaska Range Wrangellia composite terrane Hines Creek fault Talkeetna fault Earth Sciences text 2011 ftpurdueuniv https://doi.org/10.1029/2011GC003519 2023-06-12T20:39:08Z A first-order process in the growth of continents is the collision and accretion of terranes against continental margins. Collision leads to the formation of a suture zone between the accreted terrane and the former continental margin. New insights on the suturing process are observed from two receiver function transects across the Mesozoic Alaska Range suture zone. Three distinct crustal sections are identified from observations of crustal thickness, intracrustal discontinuities, and Vp/Vs: a northern section with ∼27 km thick crust of felsic to intermediate composition, a central section that is ∼37 km thick that exhibits intracrustal discontinuities and has felsic to intermediate composition, and a southern section that is ∼30 km thick and has a more mafic composition. We interpret these sections to correspond with the former continental margin (Yukon composite terrane), the suture zone proper, and the allochthonous oceanic terrane (Wrangellia composite terrane). The boundary between the Yukon composite terrane and the suture zone appears to be a subhorizontal discontinuity that accommodated underthrusting of crust from the suture zone beneath the former continental margin. The boundary between the suture zone and the Wrangellia composite terrane, in contrast, appears to be a relatively discrete, vertical boundary. The observed variability in the crust across the Alaska Range suture zone is likely controlled by the differing compositions of the terranes involved, which influences how each section responds to precollisional, syncollisional, and postcollisional deformation. Text alaska range Alaska Yukon Purdue University: e-Pubs Hines ENVELOPE(13.035,13.035,66.243,66.243) Hines Creek ENVELOPE(-118.619,-118.619,55.917,55.917) Yukon Geochemistry, Geophysics, Geosystems 12 4 n/a n/a |
institution |
Open Polar |
collection |
Purdue University: e-Pubs |
op_collection_id |
ftpurdueuniv |
language |
unknown |
topic |
receiver functions suture zone Alaska Range Wrangellia composite terrane Hines Creek fault Talkeetna fault Earth Sciences |
spellingShingle |
receiver functions suture zone Alaska Range Wrangellia composite terrane Hines Creek fault Talkeetna fault Earth Sciences Brennan, P.R.K. Gilbert, H. Ridgway, K. D. Crustal structure across the central Alaska Range: Anatomy of a Mesozoic collisional zone |
topic_facet |
receiver functions suture zone Alaska Range Wrangellia composite terrane Hines Creek fault Talkeetna fault Earth Sciences |
description |
A first-order process in the growth of continents is the collision and accretion of terranes against continental margins. Collision leads to the formation of a suture zone between the accreted terrane and the former continental margin. New insights on the suturing process are observed from two receiver function transects across the Mesozoic Alaska Range suture zone. Three distinct crustal sections are identified from observations of crustal thickness, intracrustal discontinuities, and Vp/Vs: a northern section with ∼27 km thick crust of felsic to intermediate composition, a central section that is ∼37 km thick that exhibits intracrustal discontinuities and has felsic to intermediate composition, and a southern section that is ∼30 km thick and has a more mafic composition. We interpret these sections to correspond with the former continental margin (Yukon composite terrane), the suture zone proper, and the allochthonous oceanic terrane (Wrangellia composite terrane). The boundary between the Yukon composite terrane and the suture zone appears to be a subhorizontal discontinuity that accommodated underthrusting of crust from the suture zone beneath the former continental margin. The boundary between the suture zone and the Wrangellia composite terrane, in contrast, appears to be a relatively discrete, vertical boundary. The observed variability in the crust across the Alaska Range suture zone is likely controlled by the differing compositions of the terranes involved, which influences how each section responds to precollisional, syncollisional, and postcollisional deformation. |
format |
Text |
author |
Brennan, P.R.K. Gilbert, H. Ridgway, K. D. |
author_facet |
Brennan, P.R.K. Gilbert, H. Ridgway, K. D. |
author_sort |
Brennan, P.R.K. |
title |
Crustal structure across the central Alaska Range: Anatomy of a Mesozoic collisional zone |
title_short |
Crustal structure across the central Alaska Range: Anatomy of a Mesozoic collisional zone |
title_full |
Crustal structure across the central Alaska Range: Anatomy of a Mesozoic collisional zone |
title_fullStr |
Crustal structure across the central Alaska Range: Anatomy of a Mesozoic collisional zone |
title_full_unstemmed |
Crustal structure across the central Alaska Range: Anatomy of a Mesozoic collisional zone |
title_sort |
crustal structure across the central alaska range: anatomy of a mesozoic collisional zone |
publisher |
Purdue University |
publishDate |
2011 |
url |
https://docs.lib.purdue.edu/easpubs/10 https://doi.org/10.1029/2011GC003519 https://docs.lib.purdue.edu/context/easpubs/article/1002/viewcontent/Brennan.pdf |
long_lat |
ENVELOPE(13.035,13.035,66.243,66.243) ENVELOPE(-118.619,-118.619,55.917,55.917) |
geographic |
Hines Hines Creek Yukon |
geographic_facet |
Hines Hines Creek Yukon |
genre |
alaska range Alaska Yukon |
genre_facet |
alaska range Alaska Yukon |
op_source |
Department of Earth, Atmospheric, and Planetary Sciences Faculty Publications |
op_relation |
https://docs.lib.purdue.edu/easpubs/10 doi:10.1029/2011GC003519 https://docs.lib.purdue.edu/context/easpubs/article/1002/viewcontent/Brennan.pdf |
op_doi |
https://doi.org/10.1029/2011GC003519 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
12 |
container_issue |
4 |
container_start_page |
n/a |
op_container_end_page |
n/a |
_version_ |
1770274628528242688 |