Open AccessUpper mantle beneath the Eger Rift (Central Europe): plume or asthenosphere upwelling?
Author(s) -
Plomerová Jaroslava,
Achauer Ulrich,
Babuška Vladislav,
Vecsey Luděk
Publication year - 2007
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.2007.03361.x
Subject(s) - geology , asthenosphere , lithosphere , rift , mantle (geology) , massif , seismic anisotropy , seismology , mantle plume , geophysics , upwelling , shear wave splitting , transition zone , tectonics , paleontology , oceanography
SUMMARY We present the first results of a high‐resolution teleseismic traveltime tomography and seismic anisotropy study of the lithosphere–asthenosphere system beneath the western Bohemian Massif. The initial high‐resolution tomography down to a depth of 250 km did not image any columnar low‐velocity anomaly which could be interpreted as a mantle plume anticipated beneath the Eger Rift, similar to recent findings of small plumes beneath the French Massif Central and the Eifel in Germany. Alternatively, we interpret the broad low‐velocity anomaly beneath the Eger Rift by an upwelling of the lithosphere–asthenosphere transition. We also map lateral variations of seismic anisotropy of the mantle lithosphere from spatial variations of P ‐wave delay times and the shear wave splitting. Three major domains characterised by different orientations of seismic anisotropy correspond to the major tectonic units—Saxothuringian, Moldanubian and the Teplá‐Barrandian—and their fabrics fit to those found in our previous studies of mantle anisotropy on large European scales.