Topographic Imaging of European Mantle Plumes
Abstract
Recent numerical experiments based on tectonically realistic formulation for the lithosphere and representative mantle rheology, have shown that plume-induced undulations exhibit temporal successions of uplift and subsidence at various wavelengths (A). From spectral (Fourier) analyses of the undulations would appear that two groups of wavelengths (200-400 km and 60-100 km) predominate. Interestingly, a spectral analysis of Europe's topography also reveals two dominant groups (B). To discriminate between tectonically-induced undulations (uni-directional deformation) and plume-induced undulations (omni-directional deformation) (C), we use a spectral analysis with a wavelet formulation (D). The European lithosphere is well-suited for this approach since it has been suggested that two mantle plumes (the Massif Central and the Eifel area) underlie Western Europe (E), where Alpine compression has folded the lithosphere over several hundreds of kms. The wavelet analysis of Europe's surface topography confirms that energy distribution of the topographic undulations outside the two main volcanic provinces is homogeneous (F), thus contrasting with the large-scale and medium-scale high-energy features that are obtained for the Massif Central and Eifel areas (G). Similar signatures are also found beneath the northern Sudetes area (H).
Domains
Earth Sciences
Origin : Files produced by the author(s)