Nature · Earth Science
Sculptures carved by wind, water and time
Given enough time, wind, water and frost become master sculptors, whittling solid rock into arches, spires, balancing rocks and hoodoos. These fantastical desert and coastal forms are fleeting on geological timescales — each one a temporary masterpiece caught partway between mountain and dust.
Weathering attacks weaknesses in rock — cracks, softer layers and joints — far faster than the surrounding stone. Wind-blown sand, freeze–thaw and running water hollow out alcoves, punch through fins to make arches, and leave harder caprock protecting slender columns below.
A rock fin is hollowed from both sides until a window opens and widens into a free-standing arch.
Windows punched through rock
An arch forms when weathering breaks through a thin fin of rock, opening a window that slowly widens. Eventually every arch grows too thin and collapses — they are geologically temporary.
Waves carving the coastline
Waves exploit cracks in a headland to cut a cave, then an arch straight through it. When the arch collapses, an isolated pillar — a sea stack — is left standing offshore.
Totem-pole columns of rock
A hoodoo is a slender spire capped by a harder rock that shields the softer column beneath from erosion. Bryce Canyon’s glowing amphitheatres hold thousands of them.
Boulders poised on a pedestal
When erosion wears away the softer rock beneath a resistant boulder, the boulder is left improbably balanced on a narrow pedestal — a natural sculpture waiting to fall.