I left San Antonio on May 30; my first destination was several National Parks in the Colorado Plateau.

The Colorado Plateau was formerly the site of a shallow inland sea which periodically rose and fell depositing layered rock formations. Where these have been exposed through erosion, uplift and other processes, cross-sections of these contrasting layers are revealed creating the spectacular landforms now protected within the national parks; this is probably the highest concentration of national parks in the lower 48.

Last year, I visited Petrified Forest, Grand Canyon, Zion and Bryce Canyon National Parks; this year, I headed for Arches, Canyonlands, and Capitol Reef. Each park has its own characteristic sequence of rock layers (“stratigraphy”). Once one learns the characteristics of some of these layers (e.g., the Chinle formation was deposited in low-oxygen environments such as stagnant swamps and has a characteristic gray-green color) these layers can be traced across multiple parks.