Shear wave splitting and mantle flow beneath LA RISTRA

Rengin Gök, James F. Ni, Michael West, Eric Sandvol, David Wilson, Richard Aster, W. Scott Baldridge, Stephen Grand, Wei Gao, Frederik Tillmann, Steve Semken

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

Shear-wave splitting parameters (fast polarization direction and delay time) are determined using data from LA RISTRA (Colorado pLAteau RIo Grande Rift/Great Plains Seismic TRAnsect), a deployment of broadband seismometers extending from the Great Plains, across the Rio Grande Rift and the Jemez Lineament, to the Colorado Plateau. Results show that the fast polarization directions are sub-parallel to North American absolute plate motion. The largest deviations from the plate motion are observed within the western edge of the Great Plains and in the interior of the Colorado Plateau where lithospheric anisotropy may be significant. Delay times range from 0.8 to 1.8 seconds with an average value of 1.4 seconds; the largest values are along the Jemez Lineament and the Rio Grande Rift which are underlain by an uppermost mantle low velocity zone extending to depths of ∼200 km. The anisotropy beneath the central part of LA RISTRA shows a remarkably consistent pattern with a mean fast direction of 40° ± 6°. Seismic anisotropy can be explained by differential horizontal motion between the North American lithosphere and westerly to southwesterly flow of the asthenospheric mantle. The approximately N-S fast direction found beneath western Texas is similar to that observed beneath the southern rift and may reflect a different dynamic regime.

Original languageEnglish (US)
Pages (from-to)16-11
Number of pages6
JournalGeophysical Research Letters
Volume30
Issue number12
StatePublished - Jun 15 2003
Externally publishedYes

Fingerprint

wave splitting
Colorado Plateau (US)
S waves
S-wave
Earth mantle
plains
plate motion
plateau
Rio Grande (North America)
mantle
lineament
anisotropy
polarization
seismic anisotropy
time lag
low velocity zone
seismograph
westerly
seismographs
lithosphere

ASJC Scopus subject areas

  • Earth and Planetary Sciences (miscellaneous)

Cite this

Gök, R., Ni, J. F., West, M., Sandvol, E., Wilson, D., Aster, R., ... Semken, S. (2003). Shear wave splitting and mantle flow beneath LA RISTRA. Geophysical Research Letters, 30(12), 16-11.

Shear wave splitting and mantle flow beneath LA RISTRA. / Gök, Rengin; Ni, James F.; West, Michael; Sandvol, Eric; Wilson, David; Aster, Richard; Baldridge, W. Scott; Grand, Stephen; Gao, Wei; Tillmann, Frederik; Semken, Steve.

In: Geophysical Research Letters, Vol. 30, No. 12, 15.06.2003, p. 16-11.

Research output: Contribution to journalArticle

Gök, R, Ni, JF, West, M, Sandvol, E, Wilson, D, Aster, R, Baldridge, WS, Grand, S, Gao, W, Tillmann, F & Semken, S 2003, 'Shear wave splitting and mantle flow beneath LA RISTRA', Geophysical Research Letters, vol. 30, no. 12, pp. 16-11.
Gök R, Ni JF, West M, Sandvol E, Wilson D, Aster R et al. Shear wave splitting and mantle flow beneath LA RISTRA. Geophysical Research Letters. 2003 Jun 15;30(12):16-11.
Gök, Rengin ; Ni, James F. ; West, Michael ; Sandvol, Eric ; Wilson, David ; Aster, Richard ; Baldridge, W. Scott ; Grand, Stephen ; Gao, Wei ; Tillmann, Frederik ; Semken, Steve. / Shear wave splitting and mantle flow beneath LA RISTRA. In: Geophysical Research Letters. 2003 ; Vol. 30, No. 12. pp. 16-11.
@article{22d2341fe4a34a2abf0328db9671c840,
title = "Shear wave splitting and mantle flow beneath LA RISTRA",
abstract = "Shear-wave splitting parameters (fast polarization direction and delay time) are determined using data from LA RISTRA (Colorado pLAteau RIo Grande Rift/Great Plains Seismic TRAnsect), a deployment of broadband seismometers extending from the Great Plains, across the Rio Grande Rift and the Jemez Lineament, to the Colorado Plateau. Results show that the fast polarization directions are sub-parallel to North American absolute plate motion. The largest deviations from the plate motion are observed within the western edge of the Great Plains and in the interior of the Colorado Plateau where lithospheric anisotropy may be significant. Delay times range from 0.8 to 1.8 seconds with an average value of 1.4 seconds; the largest values are along the Jemez Lineament and the Rio Grande Rift which are underlain by an uppermost mantle low velocity zone extending to depths of ∼200 km. The anisotropy beneath the central part of LA RISTRA shows a remarkably consistent pattern with a mean fast direction of 40° ± 6°. Seismic anisotropy can be explained by differential horizontal motion between the North American lithosphere and westerly to southwesterly flow of the asthenospheric mantle. The approximately N-S fast direction found beneath western Texas is similar to that observed beneath the southern rift and may reflect a different dynamic regime.",
author = "Rengin G{\"o}k and Ni, {James F.} and Michael West and Eric Sandvol and David Wilson and Richard Aster and Baldridge, {W. Scott} and Stephen Grand and Wei Gao and Frederik Tillmann and Steve Semken",
year = "2003",
month = "6",
day = "15",
language = "English (US)",
volume = "30",
pages = "16--11",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "American Geophysical Union",
number = "12",

}

TY - JOUR

T1 - Shear wave splitting and mantle flow beneath LA RISTRA

AU - Gök, Rengin

AU - Ni, James F.

AU - West, Michael

AU - Sandvol, Eric

AU - Wilson, David

AU - Aster, Richard

AU - Baldridge, W. Scott

AU - Grand, Stephen

AU - Gao, Wei

AU - Tillmann, Frederik

AU - Semken, Steve

PY - 2003/6/15

Y1 - 2003/6/15

N2 - Shear-wave splitting parameters (fast polarization direction and delay time) are determined using data from LA RISTRA (Colorado pLAteau RIo Grande Rift/Great Plains Seismic TRAnsect), a deployment of broadband seismometers extending from the Great Plains, across the Rio Grande Rift and the Jemez Lineament, to the Colorado Plateau. Results show that the fast polarization directions are sub-parallel to North American absolute plate motion. The largest deviations from the plate motion are observed within the western edge of the Great Plains and in the interior of the Colorado Plateau where lithospheric anisotropy may be significant. Delay times range from 0.8 to 1.8 seconds with an average value of 1.4 seconds; the largest values are along the Jemez Lineament and the Rio Grande Rift which are underlain by an uppermost mantle low velocity zone extending to depths of ∼200 km. The anisotropy beneath the central part of LA RISTRA shows a remarkably consistent pattern with a mean fast direction of 40° ± 6°. Seismic anisotropy can be explained by differential horizontal motion between the North American lithosphere and westerly to southwesterly flow of the asthenospheric mantle. The approximately N-S fast direction found beneath western Texas is similar to that observed beneath the southern rift and may reflect a different dynamic regime.

AB - Shear-wave splitting parameters (fast polarization direction and delay time) are determined using data from LA RISTRA (Colorado pLAteau RIo Grande Rift/Great Plains Seismic TRAnsect), a deployment of broadband seismometers extending from the Great Plains, across the Rio Grande Rift and the Jemez Lineament, to the Colorado Plateau. Results show that the fast polarization directions are sub-parallel to North American absolute plate motion. The largest deviations from the plate motion are observed within the western edge of the Great Plains and in the interior of the Colorado Plateau where lithospheric anisotropy may be significant. Delay times range from 0.8 to 1.8 seconds with an average value of 1.4 seconds; the largest values are along the Jemez Lineament and the Rio Grande Rift which are underlain by an uppermost mantle low velocity zone extending to depths of ∼200 km. The anisotropy beneath the central part of LA RISTRA shows a remarkably consistent pattern with a mean fast direction of 40° ± 6°. Seismic anisotropy can be explained by differential horizontal motion between the North American lithosphere and westerly to southwesterly flow of the asthenospheric mantle. The approximately N-S fast direction found beneath western Texas is similar to that observed beneath the southern rift and may reflect a different dynamic regime.

UR - http://www.scopus.com/inward/record.url?scp=0347413678&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0347413678&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0347413678

VL - 30

SP - 16

EP - 11

JO - Geophysical Research Letters

JF - Geophysical Research Letters

SN - 0094-8276

IS - 12

ER -