Shale of various orogeny
Images (a), (b) and (d) –(f) courtesy of Dr. J. Schieber, Indiana University.

Shale of various orogeny

Color cathodoluminescence reveals provenance of populations of quartz grains (a) Cleveland shale (Devonian); low grade metamorphic acadian orogeny; (b) Barnett shale (Miss.) Texas; low grade metamorphic ouchita orogeny; (c) Unspecified; (d) Santa Barbara basin shale (modern); plutonic (Sierra Nevada) and metamorphic (recycled coast range sediments); (e) Mancos shale, Utah; low and medium grade metamotphic quartz, sevier orogeny; (f) Huroh shale (Devonian); medium grade metamorphic and plutonic. All samples prepared using Ilion+ II broad beam argon milling system.