Comparing P and S wave heterogeneity in the mantle
From the reprocessed data set of Engdahl and co-workers we have carefully selected matching P and S data for tomographic imaging. We assess data and model error and conclude that our S model uncertainty is twice that of the P model. We account for this in our comparison of the perturbations in P and...
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
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American Geophysical Union (AGU)
2017
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| Online Access: | http://hdl.handle.net/1721.1/107741 https://orcid.org/0000-0003-1650-6818 |
| _version_ | 1811078191540862976 |
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| author | Saltzer, Rebecca L. van der Hilst, Robert D Karason, Hrafnkell |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Saltzer, Rebecca L. van der Hilst, Robert D Karason, Hrafnkell |
| author_sort | Saltzer, Rebecca L. |
| collection | MIT |
| description | From the reprocessed data set of Engdahl and co-workers we have carefully selected matching P and S data for tomographic imaging. We assess data and model error and conclude that our S model uncertainty is twice that of the P model. We account for this in our comparison of the perturbations in P and S-wavespeed. In accord with previous studies we find that P and S perturbations are positively correlated at all depths. However, in the deep mantle systematic differences occur between regions that have undergone subduction in the last 120 million years and those that have not. In particular, below 1500 km depth ∂ln V[subscript s]/∂ln V[subscript p] is significantly larger in mantle regions away from subduction than in mantle beneath convergent margins. This inference is substantiated by wavespeed analyses with random realizations of the slab/non-slab distribution. Through much of the mantle there is no significant correlation between bulk sound and S-wave perturbations, but they appear to be negatively correlated between 1700 and 2100 km depth, which is also where the largest differences in ∂ln V[subscript s]/∂ln V[subscript p] occur. This finding supports convection models with compositional heterogeneity in the lowermost mantle. |
| first_indexed | 2024-09-23T10:55:22Z |
| format | Article |
| id | mit-1721.1/107741 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T10:55:22Z |
| publishDate | 2017 |
| publisher | American Geophysical Union (AGU) |
| record_format | dspace |
| spelling | mit-1721.1/1077412022-09-30T23:58:58Z Comparing P and S wave heterogeneity in the mantle Saltzer, Rebecca L. van der Hilst, Robert D Karason, Hrafnkell Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Saltzer, Rebecca L. van der Hilst, Robert D Karason, Hrafnkell From the reprocessed data set of Engdahl and co-workers we have carefully selected matching P and S data for tomographic imaging. We assess data and model error and conclude that our S model uncertainty is twice that of the P model. We account for this in our comparison of the perturbations in P and S-wavespeed. In accord with previous studies we find that P and S perturbations are positively correlated at all depths. However, in the deep mantle systematic differences occur between regions that have undergone subduction in the last 120 million years and those that have not. In particular, below 1500 km depth ∂ln V[subscript s]/∂ln V[subscript p] is significantly larger in mantle regions away from subduction than in mantle beneath convergent margins. This inference is substantiated by wavespeed analyses with random realizations of the slab/non-slab distribution. Through much of the mantle there is no significant correlation between bulk sound and S-wave perturbations, but they appear to be negatively correlated between 1700 and 2100 km depth, which is also where the largest differences in ∂ln V[subscript s]/∂ln V[subscript p] occur. This finding supports convection models with compositional heterogeneity in the lowermost mantle. National Science Foundation (U.S.) (Grant EAR-9905779) 2017-03-27T21:03:43Z 2017-03-27T21:03:43Z 2001-04 2000-09 Article http://purl.org/eprint/type/JournalArticle 0094-8276 http://hdl.handle.net/1721.1/107741 Saltzer, R. L., R. D. van der Hilst, and H. Kárason. “Comparing P and S Wave Heterogeneity in the Mantle.” Geophysical Research Letters 28.7 (2001): 1335–1338. © 2001 American Geophysical Union https://orcid.org/0000-0003-1650-6818 en_US http://dx.doi.org/10.1029/2000GL012339 Geophysical Research Letters Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Geophysical Union (AGU) MIT Web Domain |
| spellingShingle | Saltzer, Rebecca L. van der Hilst, Robert D Karason, Hrafnkell Comparing P and S wave heterogeneity in the mantle |
| title | Comparing P and S wave heterogeneity in the mantle |
| title_full | Comparing P and S wave heterogeneity in the mantle |
| title_fullStr | Comparing P and S wave heterogeneity in the mantle |
| title_full_unstemmed | Comparing P and S wave heterogeneity in the mantle |
| title_short | Comparing P and S wave heterogeneity in the mantle |
| title_sort | comparing p and s wave heterogeneity in the mantle |
| url | http://hdl.handle.net/1721.1/107741 https://orcid.org/0000-0003-1650-6818 |
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