"DOBREfraction'99" - Velocity model of the crust and upper mantle beneath the Donbas Foldbelt (east Ukraine).

The Donbas Foldbelt (DF) is the uplifted and deformed part of the up to 20-km-thick Dniepr-Donets Basin (DDB) that formed as the result of rifting of the East European Craton (EEC) in the Late Devonian. Uplift, especially of the southern margin of the basin, occurred in Early Permian times, in a (trans)tensional tectonic stress regime while folding and reverse faulting mainly occurred later-mainly during the Late Cretaceous. A seismic refraction/wide-angle reflection survey was carried out in 1999 (DOBREfraction'99) to complement existing Deep Seismic Sounding (DSS) data from the area that did not record significant Pn phase arrivals because of insufficient maximum offset. DOBREfraction'99 comprised some 245 recording stations along a line of 360 km length with 11 in-line shot points as well as a 100 km away, parallel 190 km long subsidiary fan profile. The main profile runs between the shores of the Azov Sea in the south to the Ukraine-Russia border in the north, across the Azov Massif (Ukrainian Shield), the Foldbelt, and the Voronezh Massif. Particular scientific targets include the nature of the crust-mantle transition and the geometry of crustal-upper mantle structures related to rifting and subsequent basin inversion. Tomographic inversion as well as ray-trace based velocity modelling has been carried out. The velocity signature of the sedimentary basin itself is well resolved, indicating an asymmetric form, with a steeper basement surface in the south than in the north, and a total thickness of about 20 km. A thick (>10 km) high velocity (>6.9 km/s) lower crustal body lies beneath the rift basin itself, offset slightly to the north compared to the main basin depocentre, likely related to the rifting processes. Velocities in the crust below the Ukrainian Shield, south of the Foldbelt, are in general higher than beneath the Voronezh Massif to the north. The Moho displays only slight topography around a depth of 40 km along the profile. © 2003 Elsevier B.V. All rights reserved

The Moho depth map of the European Plate

The European Plate has a 4.5 Gy long and complex tectonic history. This is reflected in the present-day large-scale crustal structures. A new digital Moho depth map is compiled from more than 250 data sets of individual seismic profiles, 3-D models obtained by body and surface waves, receiver function results and maps of seismic and/or gravity data compilations. We have compiled the first digital, high-resolution map of the Moho depth for the whole European Plate, extending from the mid-Atlantic ridge in the west to the Ural Mountains in the east, and from the Mediterranean Sea in the south to the Barents Sea and Spitsbergen in the Arctic in the north. In general, three large domains within the European Plate crust are visible. The oldest Archean and Proterozoic crust has a thickness of 40–60 km, the continental Variscan and Alpine crust has a thickness of 20–40 km, and the youngest oceanic Atlantic crust has a thickness of 10–20 km