| Sandstones and volcanic tuffs of the Middle Miocene Ricardo Group (roughly 10 million years old) are wonderfully exposed in Hagen Canyon. Blackish rocks at top of image are remnants of a volcanic basalt flow during Miocene times. |
| Sandstones and volcanic tuffs of the Middle Miocene Ricardo Group (roughly 10 million years old) are wonderfully exposed in Hagen Canyon. Blackish rocks at top of image are remnants of a volcanic basalt flow during Miocene times. |