Crustal structure of the West Antarctic rift system and Marie Byrd Land hotspot

J. Paul Winberry, Sridhar Anandakrishnan

Research output: Contribution to journalArticle

76 Citations (Scopus)

Abstract

The West Antarctic rift system is one of the largest zones of continental extension on Earth. However, little is known of its crustal structure owing to the vast ice sheet that dominates the region. We report on new insights gained from a recent broadband seismic experiment. The 25-km-thick crust measured on the southern flank of the Marie Byrd Land dome suggests that the high topography there is partially supported by a low-density mantle, possibly a hotspot, whereas the interior of the rift appears to be underlain by average-density mantle, suggesting that active volcanism is not present beneath the interior of the West Antarctic Ice Sheet. The fact that a crustal thickness of only 21 km was measured in the Bentley subglacial trench suggests that the region has undergone locally extreme extension.

Original languageEnglish (US)
Pages (from-to)977-980
Number of pages4
JournalGeology
Volume32
Issue number11
DOIs
StatePublished - Nov 1 2004

Fingerprint

crustal structure
ice sheet
hot spot
mantle
crustal thickness
dome
trench
volcanism
topography
crust
experiment
land

All Science Journal Classification (ASJC) codes

  • Geology

Cite this

@article{4c0224879d1a4794badcdab0d4539739,
title = "Crustal structure of the West Antarctic rift system and Marie Byrd Land hotspot",
abstract = "The West Antarctic rift system is one of the largest zones of continental extension on Earth. However, little is known of its crustal structure owing to the vast ice sheet that dominates the region. We report on new insights gained from a recent broadband seismic experiment. The 25-km-thick crust measured on the southern flank of the Marie Byrd Land dome suggests that the high topography there is partially supported by a low-density mantle, possibly a hotspot, whereas the interior of the rift appears to be underlain by average-density mantle, suggesting that active volcanism is not present beneath the interior of the West Antarctic Ice Sheet. The fact that a crustal thickness of only 21 km was measured in the Bentley subglacial trench suggests that the region has undergone locally extreme extension.",
author = "Winberry, {J. Paul} and Sridhar Anandakrishnan",
year = "2004",
month = "11",
day = "1",
doi = "10.1130/G20768.1",
language = "English (US)",
volume = "32",
pages = "977--980",
journal = "Geology",
issn = "0091-7613",
publisher = "Geological Society of America",
number = "11",

}

Crustal structure of the West Antarctic rift system and Marie Byrd Land hotspot. / Winberry, J. Paul; Anandakrishnan, Sridhar.

In: Geology, Vol. 32, No. 11, 01.11.2004, p. 977-980.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Crustal structure of the West Antarctic rift system and Marie Byrd Land hotspot

AU - Winberry, J. Paul

AU - Anandakrishnan, Sridhar

PY - 2004/11/1

Y1 - 2004/11/1

N2 - The West Antarctic rift system is one of the largest zones of continental extension on Earth. However, little is known of its crustal structure owing to the vast ice sheet that dominates the region. We report on new insights gained from a recent broadband seismic experiment. The 25-km-thick crust measured on the southern flank of the Marie Byrd Land dome suggests that the high topography there is partially supported by a low-density mantle, possibly a hotspot, whereas the interior of the rift appears to be underlain by average-density mantle, suggesting that active volcanism is not present beneath the interior of the West Antarctic Ice Sheet. The fact that a crustal thickness of only 21 km was measured in the Bentley subglacial trench suggests that the region has undergone locally extreme extension.

AB - The West Antarctic rift system is one of the largest zones of continental extension on Earth. However, little is known of its crustal structure owing to the vast ice sheet that dominates the region. We report on new insights gained from a recent broadband seismic experiment. The 25-km-thick crust measured on the southern flank of the Marie Byrd Land dome suggests that the high topography there is partially supported by a low-density mantle, possibly a hotspot, whereas the interior of the rift appears to be underlain by average-density mantle, suggesting that active volcanism is not present beneath the interior of the West Antarctic Ice Sheet. The fact that a crustal thickness of only 21 km was measured in the Bentley subglacial trench suggests that the region has undergone locally extreme extension.

UR - http://www.scopus.com/inward/record.url?scp=9144219623&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=9144219623&partnerID=8YFLogxK

U2 - 10.1130/G20768.1

DO - 10.1130/G20768.1

M3 - Article

AN - SCOPUS:9144219623

VL - 32

SP - 977

EP - 980

JO - Geology

JF - Geology

SN - 0091-7613

IS - 11

ER -