Together, the cuts expose a variety of colors, textures, and compositions of most of the volcanic rock in this section of our tour. Continuing on, our route follows Limpia Creek and hilly, grass-covered slopes appear in front of us as the canyon begins to widen. The white domes of the University of Texas McDonald Observatory can be seen on the horizon to the north. And as the road straightens and heads to the west, Mount Livermore looms high in the distance, and is easily identified by its distinctive knobbed-tipped summit. The grassy slopes in the foreground are sporadically crowned by pinnacle-shaped outcrops of volcanic rock.
Casket Mountain is the aptly-named peak on our right to the north of the Prude Ranch.
Soon the road turns to the north again as we pass the Central and Southwest Solar Park and begins to climb the south face of Mount Locke where the Observatory is perched. About halfway up our ascent, there is a wide pullout and scenic overlook that is a popular stop for amateur geologists and school field trips. Here, a large wall of lava flow is exposed resting on a ash-flow tuff, turned red in a soil zone. Bisecting the lava wall is a near vertical white, siliceous dike , turned quartz at its baked edges. Dikes result from magma that is forced upward along fractures and cracks to produce walls of hardened rock.