Present-day vertical movements in the southern part of the Rhinegraben (France)

Active deformation in the southern part of the Rhinegraben, studied by comparing leveling measurements, is characterized by vertical movements. Upward movements greater than I. mm.y(-1) have been measured near Mulhouse and Selestat. Smaller rates of uplift averaging 1 mm.y(-1) were also observed above some groups of salt plugs striking NW-SE. Both types of vertical uplift are compatible with the regional stress field. The movements may be associated with the reactivation of NE-striking Variscan thrusts and with continuing upward growth of those salt plugs that are perpendicular to the minimum horizontal stress. ((C) Academie des sciences / Elsevier, Paris.)