Types of Sedimentary Rocks Types of Sedimentary Rocks Conglomerate in the Mojave Desert. Here the cobbles and pebbles are mostly volcanic rocks and lie in a matrix of volcanically derived sand. Spectacular breccia in Mosaic Canyon, Death Valley National Park. Cross-bedding in the Coconino sandstone, along the Kaibab Trail in the Grand Canyon. Evaporites in the process of formation, Devil's Golf Course, Death Valley.
Brines evaporate to a variety of different salts.
A view across the Devil's Golf Course. Pretty rough going. Tilted shales and sandstones in Rainbow Basin, near Barstow, California. White layers are thin tuffs. Barstow is in the middle of the Mojave Desert and is the western terminus of Interstate 40, a mere 2500 miles down the road from Chapel Hill.