Anomalously deep mantle transition zone below Central Europe: Evidence of lithospheric instability

摘要: [1] The depths of the 410 and 660 km phase transitions provide critical information on thermal state mantle transition zone (MTZ) and, by implication, circulation upper mantle. We analyze converted seismic waves to produce a high resolution image these discontinuities beneath Pannonian Basin Central Europe. Models explain extension basin in Middle Miocene involve subduction roll-back gravitational instability an over-thickened lithosphere. find that cold dense material appears have accumulated MTZ, consistent with idea supply from several episodes, or overturn. Variation depth discontinuity as much 40 suggests lithospheric is ponding top this transition. Where deepest, eventual transfer into lower may be expected develop.