These depressions generally consist of silty clay and caliche material. Natural resources included caliche, sand, gravel, oil, and gas. Other guardrails were installed around area caliche pits. Sodium iodate is extracted from the caliche and reduced to iodide by sodium bisulfite. However, caliche deposits indicate at least periodic droughts. However, caliche deposits indicate at least periodic droughts occurred. Soil saturation above the caliche bed can make the condition worse. Third, caliche beds can also cause the surrounding soil to be basic. Other geologic features of note on the islands include beachrock, eolianite, and caliche pseudomorphs. They are almost exclusively known from the caliche deposits of Chile. The term "caliche" is Spanish and is originally from the Latin "calx", meaning lime. House design evolved into post-reinforced pit-houses, covered with caliche adobe. The bus fell into a caliche pit with about of water. U.D. Horadada has several sponsors, including Grupo Caliche and the Town Hall. The local Spanish vernacular is called "Caliche".