Notice the poorly sorted material (sediments of all different sizes) and the various rock types? Most of the rock fragments we see in the lahar are andesite (a dark, fine-grained volcanic rock) with some Cripple Creek Granite (course-crystalline with reddish-orange feldspar). Some of the more rounded cobbles may have been picked up along the stream channel in the paleovalley that the lahar followed. This location is near the contact between the Pikes Peak Granite (1.08 billion years old), which lies to the east of this site, and the much older Cripple Creek Granite (1.40-1.43 billion years old) which lies to the west. These two granitic rocks both formed in a batholith (a magma chamber that cooled underground), but came from different sources.