From the core of the Alps, this eclogite represents a sliver of oceanic crust that became trapped and caught up in the continental collision that formed the Alps. The red garnet and spinach green clinopyroxene indicate that the rock recrystallized at depths of 50 to 60 kilometers and at temperatures of about 600 degrees Centigrade. The white mineral (epidote) formed later, during uplift and cooling.
Provided by Prof. Volker Dietrich, Eidgenossische Technische Hochschule, Zurich, Switzerland
Topic: Earth Science
Subtopic: Mountain Building
Keywords: Alps, Eclogite, Orogeny