Carboniferous convergence and subsequent crustal extension in the southern Schwarzwald (SW Germany)

AbstractDetailed structural analysis in the southwestern part of the Variscan Sehwarzwald Massif (SW Germany) indicates polyphase, synmetamorphic deformation in ductile shear zones. The tectono-melainnrphir evolution is characterized by orogenic crustal shortening and subsequent late- orogenic crustal extension in Carboniferous times. Convergence is responsible for an KSK trending, north dipping thrust zone with intense deformation in orthogneissic S-C type mylonites Superposed on schistose and folded metasediments presumably lower Carboniferous in age. Southeastward thrust-’“g parallel to pervasive stretching lineation, similar to the pre-dominant oblique convergent structures ill the central part of the massif, is related to crustal stacking. Relations of early granite intrusions with the outlasting retrograde tectonics Point to a Lower Carboniferous (Late-Visean) age of shortening.Subsequent crustal extension is indicated by a broad N-S trending and west dipping ductile shear zone within high grade mee...