Fig. 5

Field occurrence of Matterhorn gabbro. a Massive internally undeformed gabbro body with tectonic contact to the Arolla gneisses marked with locally altered gabbro mylonites (GG). View of the right side of Fig. 4; b Top of the Matterhorn gabbro body with sharp tectonic contact to the Arolla gneisses of the Dent Blanche nappe (DBN). View from the ridge above Colle del Leone to the East. In the background Mone Rosa (see Fig. 1)