Whirlwinds, dry convective helical vortices, move large gypsum crystals in the Andes Mountains of northern Chile. The crystals are entrained from a saline pan surface, where they grew in shallow surface brines. They are transported as much as 5 km and deposited in large dune-like mounds. The dune gravel is cemented relatively quickly by gypsum cement precipitating from near-surface saline groundwater, resulting in gypsum breccia. This marks the first occurrence of gravel-sized grains moved efficiently in air by suspension, provides a new possible interpretation for some ancient breccias and conglomerates, and improves understanding of limits of extremity of Earth surface environments.

You do not have access to this content, please speak to your institutional administrator if you feel you should have access.