Colorful rocks extend across wide swaths of the Southwest, showcased in sedimentary rock formations in Zion, Arches, Capitol Reef, Canyonlands, and other national and state parks. There is an interesting story behind the spectacular bedrock “palette” of rich shades of pink and red, purple and creamy white, and yellow and green tones.
Iron-oxide concretions – curious-looking dark spheres – can be found by the hundreds of thousands in the dramatic red and white outcrops of Navajo Sandstone in Utah. The concretions typically consist of a sandstone core surrounded by a thick iron-rich rind, and they have an interesting geologic history and Native American cultural history. They also resemble Martian spherules or "blueberries", and may share similar origins.
Towering cliffs, plateaus, arches, and narrow canyons are iconic symbols of southern Utah’s Red Rock Country. Another type of landform captured my attention during recent explorations: mile after mile of gently rolling rock-covered terrain, giving the impression of being surrounded by an ocean of sandstone. An arid sand sea of shifting dunes created these rocks many millions of years ago.