Strong seismic scatterers near the core-mantle boundary north of the Pacific Anomaly
Tomographic images have shown that there are clear high-velocity heterogeneities to the north of the Pacific Anomaly near the core-mantle boundary (CMB), but the detailed structure and origin of these heterogeneities are poorly known. In this study, we analyze PKP precursors from earthquakes in the...
Published in: | Physics of the Earth and Planetary Interiors |
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Language: | English |
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Online Access: | http://ir.gig.ac.cn/handle/344008/54963 https://doi.org/10.1016/j.pepi.2016.01.007 |
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ftchacadscgigcas:oai:ir.gig.ac.cn:344008/54963 2023-05-15T13:30:36+02:00 Strong seismic scatterers near the core-mantle boundary north of the Pacific Anomaly Ma, Xiaolong Sun, Xinlei Wiens, Douglas A. Wen, Lianxing Nyblade, Andrew Anandakrishnan, Sridhar Aster, Rick Huerta, Audrey Wilson, Terry 2016-04-01 http://ir.gig.ac.cn/handle/344008/54963 https://doi.org/10.1016/j.pepi.2016.01.007 英语 eng ELSEVIER SCIENCE BV PHYSICS OF THE EARTH AND PLANETARY INTERIORS http://ir.gig.ac.cn/handle/344008/54963 doi:10.1016/j.pepi.2016.01.007 Geochemistry & Geophysics Seismic scatterers PKP precursor Subducted slabs Lateral heterogeneities Core-mantle boundary SUBDUCTED OCEANIC-CRUST DEEP EARTH DYNAMICS LOW VELOCITY ZONES LOWERMOST MANTLE WAVE SCATTERING PKP PRECURSORS INNER-CORE CHEMICAL HETEROGENEITY ATTENUATION STRUCTURES SYNTHETIC SEISMOGRAMS 期刊论文 2016 ftchacadscgigcas https://doi.org/10.1016/j.pepi.2016.01.007 2022-03-27T20:32:07Z Tomographic images have shown that there are clear high-velocity heterogeneities to the north of the Pacific Anomaly near the core-mantle boundary (CMB), but the detailed structure and origin of these heterogeneities are poorly known. In this study, we analyze PKP precursors from earthquakes in the Aleutian Islands and Kamchatka Peninsula recorded by seismic arrays in Antarctica, and find that these heterogeneities extend similar to 400 km above the CMB and are distributed between 30 degrees and 45 degrees N in latitude. The scatterers show the largest P-wave velocity perturbation of 1.0-1.2% in the center (160-180 degrees E) and similar to 0.5% to the west and east (140-160 degrees E, 180-200 degrees E). ScS-S differential travel-time residuals reveal similar features. We suggest that these seismic scatterers are the remnants of ancient subducted slab material. The lateral variations may be caused either by different slabs, or by variations in slab composition resulting from their segregation process. (C) 2016 Elsevier B.V. All rights reserved. Report Antarc* Antarctica Kamchatka Kamchatka Peninsula Aleutian Islands Guangzhou Institute of Geochemistry: GIG OpenIR (Chinese Academy of Sciences) Kamchatka Peninsula ENVELOPE(160.000,160.000,56.000,56.000) Pacific Physics of the Earth and Planetary Interiors 253 21 30 |
institution |
Open Polar |
collection |
Guangzhou Institute of Geochemistry: GIG OpenIR (Chinese Academy of Sciences) |
op_collection_id |
ftchacadscgigcas |
language |
English |
topic |
Geochemistry & Geophysics Seismic scatterers PKP precursor Subducted slabs Lateral heterogeneities Core-mantle boundary SUBDUCTED OCEANIC-CRUST DEEP EARTH DYNAMICS LOW VELOCITY ZONES LOWERMOST MANTLE WAVE SCATTERING PKP PRECURSORS INNER-CORE CHEMICAL HETEROGENEITY ATTENUATION STRUCTURES SYNTHETIC SEISMOGRAMS |
spellingShingle |
Geochemistry & Geophysics Seismic scatterers PKP precursor Subducted slabs Lateral heterogeneities Core-mantle boundary SUBDUCTED OCEANIC-CRUST DEEP EARTH DYNAMICS LOW VELOCITY ZONES LOWERMOST MANTLE WAVE SCATTERING PKP PRECURSORS INNER-CORE CHEMICAL HETEROGENEITY ATTENUATION STRUCTURES SYNTHETIC SEISMOGRAMS Ma, Xiaolong Sun, Xinlei Wiens, Douglas A. Wen, Lianxing Nyblade, Andrew Anandakrishnan, Sridhar Aster, Rick Huerta, Audrey Wilson, Terry Strong seismic scatterers near the core-mantle boundary north of the Pacific Anomaly |
topic_facet |
Geochemistry & Geophysics Seismic scatterers PKP precursor Subducted slabs Lateral heterogeneities Core-mantle boundary SUBDUCTED OCEANIC-CRUST DEEP EARTH DYNAMICS LOW VELOCITY ZONES LOWERMOST MANTLE WAVE SCATTERING PKP PRECURSORS INNER-CORE CHEMICAL HETEROGENEITY ATTENUATION STRUCTURES SYNTHETIC SEISMOGRAMS |
description |
Tomographic images have shown that there are clear high-velocity heterogeneities to the north of the Pacific Anomaly near the core-mantle boundary (CMB), but the detailed structure and origin of these heterogeneities are poorly known. In this study, we analyze PKP precursors from earthquakes in the Aleutian Islands and Kamchatka Peninsula recorded by seismic arrays in Antarctica, and find that these heterogeneities extend similar to 400 km above the CMB and are distributed between 30 degrees and 45 degrees N in latitude. The scatterers show the largest P-wave velocity perturbation of 1.0-1.2% in the center (160-180 degrees E) and similar to 0.5% to the west and east (140-160 degrees E, 180-200 degrees E). ScS-S differential travel-time residuals reveal similar features. We suggest that these seismic scatterers are the remnants of ancient subducted slab material. The lateral variations may be caused either by different slabs, or by variations in slab composition resulting from their segregation process. (C) 2016 Elsevier B.V. All rights reserved. |
format |
Report |
author |
Ma, Xiaolong Sun, Xinlei Wiens, Douglas A. Wen, Lianxing Nyblade, Andrew Anandakrishnan, Sridhar Aster, Rick Huerta, Audrey Wilson, Terry |
author_facet |
Ma, Xiaolong Sun, Xinlei Wiens, Douglas A. Wen, Lianxing Nyblade, Andrew Anandakrishnan, Sridhar Aster, Rick Huerta, Audrey Wilson, Terry |
author_sort |
Ma, Xiaolong |
title |
Strong seismic scatterers near the core-mantle boundary north of the Pacific Anomaly |
title_short |
Strong seismic scatterers near the core-mantle boundary north of the Pacific Anomaly |
title_full |
Strong seismic scatterers near the core-mantle boundary north of the Pacific Anomaly |
title_fullStr |
Strong seismic scatterers near the core-mantle boundary north of the Pacific Anomaly |
title_full_unstemmed |
Strong seismic scatterers near the core-mantle boundary north of the Pacific Anomaly |
title_sort |
strong seismic scatterers near the core-mantle boundary north of the pacific anomaly |
publisher |
ELSEVIER SCIENCE BV |
publishDate |
2016 |
url |
http://ir.gig.ac.cn/handle/344008/54963 https://doi.org/10.1016/j.pepi.2016.01.007 |
long_lat |
ENVELOPE(160.000,160.000,56.000,56.000) |
geographic |
Kamchatka Peninsula Pacific |
geographic_facet |
Kamchatka Peninsula Pacific |
genre |
Antarc* Antarctica Kamchatka Kamchatka Peninsula Aleutian Islands |
genre_facet |
Antarc* Antarctica Kamchatka Kamchatka Peninsula Aleutian Islands |
op_relation |
PHYSICS OF THE EARTH AND PLANETARY INTERIORS http://ir.gig.ac.cn/handle/344008/54963 doi:10.1016/j.pepi.2016.01.007 |
op_doi |
https://doi.org/10.1016/j.pepi.2016.01.007 |
container_title |
Physics of the Earth and Planetary Interiors |
container_volume |
253 |
container_start_page |
21 |
op_container_end_page |
30 |
_version_ |
1766010531978674176 |