Tag Archive for: Washington County
Zion National Park, Washington County, Utah
Photographer: Tyler Knudsen; © 2013
Fall foliage adorns the already colorful walls of Jurassic-age Navajo Sandstone in the Zion Narrows. The North Fork of the Virgin River has cut the 1000-foot-deep Narrows in a relatively short span of geologic time (about 1 to 2 million years).
Towering walls of Jurassic-age Navajo Sandstone guard the historic pioneer cemetery atop Moquitch Hill in lower Zion Canyon. The cemetery serves as the final resting place for many founders of the Town of Springdale.
Eroded fragments of a dark ironstone layer contrast sharply against the pale-orange Jurassic-age Navajo Sandstone at Snow Canyon State Park. In places, the iron- and manganese-rich ironstone forms a resistant cap at the top of sandstone columns or pillars called hoodoos.
Towering cliffs of Jurassic-age sandstone constrict lower Zion Canyon. The prominently cross-bedded Navajo Sandstone, deposited in a vast dune field comparable to that of the modern-day Sahara, forms the cliffs, including the narrow spine of Angels Landing at left.
Sculpted hills of iron-stained Jurassic-age Navajo Sandstone form the Red Mountains north of St. George. In the distance, Paleozoic strata of Square Top Mountain and Jackson Peak have been transported up and over younger Mesozoic strata along the Square Top Mountain thrust fault.
Sandstone Mountain, Red Cliffs Desert Reserve, Washington County, Utah
Photographer: Tyler Knudsen; © 2012
Shifting sands partially bury an unusually large (about 1 foot in diameter) spherical hematite concretion that has eroded from the nearby Jurassic-age Navajo Sandstone. The concretion’s dark concentric bands formed when iron-oxide minerals precipitated out of groundwater that flowed through the sandstone.