The crustal and upper-mantle geophysical signature of narrow continental rifts in the Pannonian Basin

Abstract

The Pannonian basin provides a very good opportunity to study extensional tectonics. The image of narrow continental rifts, which represent one of the modes of continental extensional tectonics, was studied in detail in the Bekes basin. In order to constrain the lithosphere structure beneath the narrow rifts in the Pannonian basin, density models and interpretation of magnetotelluric measurements along the Pannonian Geotraverse are presented. The results obtained agree with the most recent deep seismic data. Most of the narrow rifts in the Pannonian basin are characterized not only by thinner crust but also by thinner lithosphere. A typical phenomenon of the gravity field over the central part of the narrow rifts in the Pannonian basin is the existence of a relative local gravity high. These gravity highs are probably due to intrusions of high-density masses into the lower crust and lower part of the upper crust beneath the narrow rifts, which are related to the extension of the basins (subbasins).