Please use this identifier to cite or link to this item:
http://hdl.handle.net/2122/13662
DC Field | Value | Language |
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dc.date.accessioned | 2020-09-01T06:11:06Z | - |
dc.date.available | 2020-09-01T06:11:06Z | - |
dc.date.issued | 2020-07 | - |
dc.identifier.uri | http://hdl.handle.net/2122/13662 | - |
dc.description.abstract | We investigate the mantle transition zone beneath the Chile‐Argentina flat subduction region by means of P‐to‐S conversions at mantle discontinuities from teleseismic events recorded at 103 seismic stations. From the analysis of receiver functions, we obtain clear converted phases from the 410 and 660 discontinuities, and we identify a robust precursory signal to P660s, of negative amplitude, that we name P590s. We observe little frequency dependence in the amplitude of the P410s converted phase, while the P660s is less visible toward higher frequencies. The 410 is on average deeper than 410km by 10±1km in the higher‐frequency bands, and it is relatively sharp, being consistent with a 10% velocity jump over less than 20km. The observed 660 depth varies with frequency; it is deeper by up to 18±2km for lower frequencies and close to reference at higher frequencies, being consistent with a 13% broad velocity gradient over 30–40km, probably caused by a composite of multiple phase transitions. The transition zone thickness is controlled by the frequency‐dependent depth variability of the 660. Our findings of relative depth, width, and velocity jump of the detected discontinuities, combined with tomographic images of the mantle transition zone, cannot be explained by thermal variations alone. Compositional constraints from mineral physics show that a near pyrolitic mantle is consistent with the ratio of the estimated velocity jumps. However, the negative P590s phase in this region could be signal from the velocity reduction due to basalt accumulation at the base of the transition zone. | en_US |
dc.language.iso | English | en_US |
dc.publisher.name | Wiley Agu | en_US |
dc.relation.ispartof | Journal of Geophysical Research: Solid Earth | en_US |
dc.relation.ispartofseries | /125 (2020) | en_US |
dc.title | The transition zone beneath West Argentina‐Central Chile using P‐to‐S converted waves. | en_US |
dc.type | article | en |
dc.description.status | Published | en_US |
dc.type.QualityControl | Peer-reviewed | en_US |
dc.description.pagenumber | e2020JB019446 | en_US |
dc.identifier.doi | 10.1029/2020JB019446 | en_US |
dc.description.obiettivoSpecifico | 1T. Struttura della Terra | en_US |
dc.description.journalType | JCR Journal | en_US |
dc.contributor.author | Bonatto, Luciana | - |
dc.contributor.author | Piromallo, Claudia | - |
dc.contributor.author | Cottaar, Sanne | - |
dc.contributor.department | University of La Serena, Chile | en_US |
dc.contributor.department | Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sezione Roma1, Roma, Italia | en_US |
dc.contributor.department | University of Cambridge | en_US |
item.openairetype | article | - |
item.cerifentitytype | Publications | - |
item.languageiso639-1 | en | - |
item.grantfulltext | open | - |
item.openairecristype | http://purl.org/coar/resource_type/c_18cf | - |
item.fulltext | With Fulltext | - |
crisitem.author.dept | Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sezione Roma1, Roma, Italia | - |
crisitem.author.dept | University of Cambridge | - |
crisitem.author.orcid | 0000-0001-7595-3648 | - |
crisitem.author.orcid | 0000-0003-3478-5128 | - |
crisitem.author.orcid | 0000-0003-0493-6570 | - |
crisitem.author.parentorg | Istituto Nazionale di Geofisica e Vulcanologia | - |
crisitem.department.parentorg | Istituto Nazionale di Geofisica e Vulcanologia | - |
Appears in Collections: | Article published / in press |
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File | Description | Size | Format | |
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Bonatto_etal_JGR_2020.pdf | 6.78 MB | Adobe PDF | View/Open |
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