Figure 13.11
Layered sedimentary rock formations in Bryce Canyon, Utah. The sediments that formed these rocks were laid down beginning about 63 million years ago over a period of about 23 million years by a system of streams and freshwater lakes. The oldest sediments are at the bottom (according to the principle of superposition; see Section 11.2). Hematite gives the sediments their vibrant orange color.(Bruce Gervais)