Lithosphere folding: Primary response to compression? (from central Asia to Paris basin)

We examine the role of lithosphere folding in the large-scale evolution of the continental lithosphere. Analysis of the record of recent vertical moti ons and the geometry of basin deflection for a number of sites in Europe an d worldwide suggests that lithospheric folding is a primary response of the lithosphere to recently induced compressional stress fields. Despite the w idespread opinion, folding can persist during long periods of time independ ently of the presence of many inhomogeneities such as crustal faults and in herited weakness zones. The characteristic wavelengths of folding are deter mined by the presence of young lithosphere in large parts of Europe and cen tral Asia and by the geometries of the sediment bodies acting as a load on the lithosphere in basins. The proximity of these sites to the areas of act ive tectonic compression suggests that the tectonically induced horizontal stresses are responsible for the large-scale warping of the lithosphere. Wa velengths and persistence of folding are controlled by many factors such as rheology, faulting, time after the end of the major tectonic compression, nonlinear effects, and initial geometry of the folded area. In particular, the persistence of periodical undulations in central Australia (700 Myr sin ce onset of folding) or in the Paris basin (60 Myr) long after the end of t he initial intensive tectonic compression requires a very strong rheology c ompatible with the effective elastic thickness values of about 100 km in th e first case and 50-60 km in the second case.