Migmatite Tracy Arm, Saywer Glacier, Alaska
Migmatites are rocks that contain both metamorphic and igneous phase and are formed under high pressure and temperature. These conditions exist only at depths close to earth’s mantle. Typically, the light phase contains quartz, feldspar and muscovite with lower melting points ( igneous phase) and dark minerals such as amphibolite and biotite with higher melting points in the metamorphic, non-melted state. Put both phases together, put them in a mixer and the result is a rock face that looks like a toffee mix! The length of this about 10 meters. Taken from a tour boat.
Migmatite Tracy Arm, Saywer Glacier, Alaska
Migmatites are rocks that contain both metamorphic and igneous phase and are formed under high pressure and temperature. These conditions exist only at depths close to earth’s mantle. Typically, the light phase contains quartz, feldspar and muscovite with lower melting points ( igneous phase) and dark minerals such as amphibolite and biotite with higher melting points in the metamorphic, non-melted state. Put both phases together, put them in a mixer and the result is a rock face that looks like a toffee mix! The length of this about 10 meters. Taken from a tour boat.