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| Titel |
Upper mantle structure around the Trans-European Suture Zone obtained by teleseismic tomography |
| VerfasserIn |
I. Janutyte, M. Majdanski, P. H. Voss, E. Kozlovskaya, PASSEQ Working Group |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1869-9510
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| Digitales Dokument |
URL |
| Erschienen |
In: Solid Earth ; 6, no. 1 ; Nr. 6, no. 1 (2015-01-16), S.73-91 |
| Datensatznummer |
250115387
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| Publikation (Nr.) |
 copernicus.org/se-6-73-2015.pdf |
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| Zusammenfassung |
| The presented study aims to resolve the upper mantle structure around the
Trans-European Suture Zone (TESZ), which is the major tectonic boundary in
Europe. The data of 183 temporary and permanent seismic stations operated
during the period of the PASsive Seismic Experiment (PASSEQ) 2006–2008
within the study area from Germany to Lithuania was used to compile the data
set of manually picked 6008 top-quality arrivals of P waves from teleseismic
earthquakes. We used the TELINV nonlinear teleseismic tomography algorithm to
perform the inversions. As a result, we obtain a model of P wave velocity
variations up to about ±3% with respect to the IASP91 velocity model
in the upper mantle around the TESZ. The higher velocities to the east of the
TESZ correspond to the older East European Craton (EEC), while the lower
velocities to the west of the TESZ correspond to younger western Europe. We
find that the seismic lithosphere–asthenosphere boundary (LAB) is more
distinct beneath the Phanerozoic part of Europe than beneath the Precambrian
part. To the west of the TESZ beneath the eastern part of the Bohemian
Massif, the Sudetes Mountains and the Eger Rift, the negative anomalies are
observed from a depth of at least 70 km, while under the Variscides the
average depth of the seismic LAB is about 100 km. We do not observe the
seismic LAB beneath the EEC, but beneath Lithuania we find the thickest
lithosphere of about 300 km or more. Beneath the TESZ, the asthenosphere is
at a depth of 150–180 km, which is an intermediate value between that of
the EEC and western Europe. The results imply that the seismic LAB in the
northern part of the TESZ is in the shape of a ramp dipping to the
northeasterly direction. In the southern part of the TESZ, the LAB is
shallower, most probably due to younger tectonic settings. In the northern
part of the TESZ we do not recognize any clear contact between Phanerozoic
and Proterozoic Europe, but further to the south we may refer to a sharp and
steep contact on the eastern edge of the TESZ. Moreover, beneath Lithuania at
depths of 120–150 km, we observe the lower velocity area following the
boundary of the proposed paleosubduction zone. |
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