Determination of rock densities in the Carpathian-Pannonian Basin lithosphere: based on the CELEBRATION 2000 experiment

Abstract

The international seismic project CELEBRATION 2000 brought very good information about the P-wave velocity distribution in the Carpathian-Pannonian Basin litosphere. In this paper seismic data were used for transformations of in situ P-wave velocities to in situ densities along all profiles running across the Western Carpathians and the Pannonian Basin: CEL01, CEL04, CEL05, CEL06, CEL09, CEL11 and CEL12. The calculation of rock densities in the crust and lower lithosphere was done by the transformation of seismic velocities to densities using the formulae of Sobolev-Babeyko, Christensen-Mooney and in the lower lithosphere also by Lachenbruch-Morgan’s formula. The density of the upper crust changes significantly in the vertical and horizontal directions, while the interval ranges of the calculated lower crust densities narrow down
prominently. The lower lithosphere is the most homogeneous – the intervals of the calculated densities for this layer are already very narrow. The average density of the upper crust (ρ = 2.60 g·cm⁻³) is the lowest in the Carpathian Foredeep region. On the contrary, the highest density of this layer (ρ = 2.77 g·cm⁻³) is located in the Bohemian Massif. The average densities ρ of the lower crust vary between 2.90 and 2.98 g·cm⁻³. The Palaeozoic
Platform and the East European Craton have the highest density (ρ = 2.98 g·cm⁻³ and ρ = 2.97 g·cm⁻³, respectively). The lower crust density is the lowest (ρ = 2.90 g·cm⁻³) in the Pannonian Basin. The range of calculated average densities ρ for the lower lithosphere is changed in the interval from 3.35 to 3.40 g·cm⁻³. The heaviest lower lithosphere can be observed in the East European Craton (ρ = 3.40 g·cm⁻³). The lower lithosphere of the Transdanubian Range and the Palaeozoic Platform is characterized by the lowest density ρ = 3.35 g·cm⁻³.