Carácter relicto de la Gran Duna de Iquique, Región de Tarapacá, Chile

Abstract

An inherited form: the high dune of Iquique (Tarapacá Region, Chile). On the arid coast of northernmost Chile, the surroundings of the city of Iquique show a high dune which reaches an elevation of about 250 m a.s.l. Geomorphological observations as well as the sedimentological contrast between sands from the dune and those from the neighbouring beaches imply that presently no supply of sand is available for the dune. Such evidence points to the relict character of the dune which probably formed during the last glacial period (isotopic stage 2, ca. 20,000 yr B.P.). At that time, sea-level being about 100 m below the present one, an emerged marine platform, 5 km wide, allowed an active deflation which supplied a large quantity of sand to the dune. Since the urban expansion of Iquique is threatening the existence of the dune, it is suggested to consider it as a natural monument in order to ensure its preservation.