Arch and FinArch and fin, Arches NP, Utah. Mechanical Weathering. Development of arch along joint surface,
Arches NP, Utah. Note fins in background. (ID # WE-03)
Needles DistrictThousands of feet of sedimentary rock, exposed in the canyons of SE Utah, attest to great lengths of geologic time. This particular canyon is in the Needles District of Canyonlands National Park. (Image ID # WE-14)
Chemical WeatheringDifferent effects of chemical weathering according to rock type: limestone in foreground; granite in left background, Vermont.(Image ID #WE-58)