Constraints on the lower mantle electrical conductivity from length-of-day changes
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F25%3A10510324" target="_blank" >RIV/00216208:11320/25:10510324 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=GMaMDsbv76" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=GMaMDsbv76</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.46298/jsedi.16005" target="_blank" >10.46298/jsedi.16005</a>
Alternative languages
Result language
angličtina
Original language name
Constraints on the lower mantle electrical conductivity from length-of-day changes
Original language description
We investigate how the radial profile 𝜎𝑚(𝑟 ) of the lower mantle electrical conductivity affectsthe downward continuation of the time-varying magnetic field to the core surface and the resulting invertedcore motions. We compare core flow predictions to the length-of-day (LOD) with geodetic records, in orderto assess how plausible the considered conductivity profiles are. The core flow inverse problem, mixing theinformation carried by single spherical harmonic magnetic coefficients, makes it non trivial to infer the delayexpected for LOD predictions. Our results indicate that the timescale characteristic of the mantle filter in thelow-frequency limit yields an integral measure of 𝜎𝑚(𝑟 ) allowing us to select admissible conductivity models.Models of 𝜎𝑚(𝑟 ) inferred from magnetospheric and tidal sources over the satellite era involve mantle filter lagsless than a couple of months and provide the best fit to LOD variations. Other conductivity profiles constructedbased on mineralogical properties and iron partitioning inferred for deep mantle rocks (i.e., 𝜎𝑚 increasing froma few S/m at 1200 km depth up to some tens of S/m TILDE OPERATOR+D91 300 km above the core surface, with a more conductingD" layer) are acceptable. A highly conducting layer of thickness 𝑂(10 km) or thinner cannot be excluded.
Czech name
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Czech description
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Classification
Type
J<sub>ost</sub> - Miscellaneous article in a specialist periodical
CEP classification
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OECD FORD branch
10500 - Earth and related environmental sciences
Result continuities
Project
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Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2025
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Journal of studies of earth's deep interior
ISSN
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e-ISSN
3099-2877
Volume of the periodical
1
Issue of the periodical within the volume
paper 4
Country of publishing house
FR - FRANCE
Number of pages
17
Pages from-to
1-17
UT code for WoS article
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EID of the result in the Scopus database
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