Abstract
We present the elastic properties of San Carlos olivine up to P = 12.8(8) GPa and T = 1300(200) K using Brillouin spectroscopy with CO2 laser heating. A comparison of our results with the global seismic model AK135 yields average olivine content near 410 km depth of about 37% and 43% in a dry and wet (1.9 wt % H2O) upper mantle, respectively. These olivine contents are far less than in the pyrolite model. However, comparisons of our results with regional seismic models lead to very different conclusions. High olivine contents of up to 87% are implied by seismic models of the western U.S. and eastern Pacific regions. In contrast, we infer less than 35% olivine under the central Pacific. Strong variations of olivine content and upper mantle lithologies near the 410 km discontinuity are suggested by regional seismic models.
Original language | English (US) |
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Pages (from-to) | 9611-9618 |
Number of pages | 8 |
Journal | Geophysical Research Letters |
Volume | 43 |
Issue number | 18 |
DOIs | |
State | Published - Sep 28 2016 |
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Keywords
- 410 km discontinuity
- olivine
- piclogite
- pyrolite
- sound velocities
ASJC Scopus subject areas
- Geophysics
- Earth and Planetary Sciences(all)
Cite this
Sound velocities of olivine at high pressures and temperatures and the composition of Earth's upper mantle. / Zhang, Jin S.; Bass, Jay D.
In: Geophysical Research Letters, Vol. 43, No. 18, 28.09.2016, p. 9611-9618.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Sound velocities of olivine at high pressures and temperatures and the composition of Earth's upper mantle
AU - Zhang, Jin S.
AU - Bass, Jay D
PY - 2016/9/28
Y1 - 2016/9/28
N2 - We present the elastic properties of San Carlos olivine up to P = 12.8(8) GPa and T = 1300(200) K using Brillouin spectroscopy with CO2 laser heating. A comparison of our results with the global seismic model AK135 yields average olivine content near 410 km depth of about 37% and 43% in a dry and wet (1.9 wt % H2O) upper mantle, respectively. These olivine contents are far less than in the pyrolite model. However, comparisons of our results with regional seismic models lead to very different conclusions. High olivine contents of up to 87% are implied by seismic models of the western U.S. and eastern Pacific regions. In contrast, we infer less than 35% olivine under the central Pacific. Strong variations of olivine content and upper mantle lithologies near the 410 km discontinuity are suggested by regional seismic models.
AB - We present the elastic properties of San Carlos olivine up to P = 12.8(8) GPa and T = 1300(200) K using Brillouin spectroscopy with CO2 laser heating. A comparison of our results with the global seismic model AK135 yields average olivine content near 410 km depth of about 37% and 43% in a dry and wet (1.9 wt % H2O) upper mantle, respectively. These olivine contents are far less than in the pyrolite model. However, comparisons of our results with regional seismic models lead to very different conclusions. High olivine contents of up to 87% are implied by seismic models of the western U.S. and eastern Pacific regions. In contrast, we infer less than 35% olivine under the central Pacific. Strong variations of olivine content and upper mantle lithologies near the 410 km discontinuity are suggested by regional seismic models.
KW - 410 km discontinuity
KW - olivine
KW - piclogite
KW - pyrolite
KW - sound velocities
UR - http://www.scopus.com/inward/record.url?scp=84990239801&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84990239801&partnerID=8YFLogxK
U2 - 10.1002/2016GL069949
DO - 10.1002/2016GL069949
M3 - Article
AN - SCOPUS:84990239801
VL - 43
SP - 9611
EP - 9618
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 18
ER -