ATACAMA

atacama, desert of, an arid, barren and saline region of western south america, covering the greater part of the chilean provinces of atacama and antofagasta, the argentine territory of los andes, and the south-western corner of the bolivian department of potosi. the higher elevations are known as the puna de atacama, which is practically a continuation southward of the great _puna_ region of peru and bolivia. it is a broken, mountainous region, volcanic in places, saline in others, and ranges from 7000 to 13,500 ft. in general elevation. its culminating ridges are marked by an irregular line of peaks and extinct volcanoes extending north by east from about 28 deg. s. into southern bolivia. on the eastern side, occasional rainfalls occur and streams from the snow-clads peaks produce some slight displays of fertility, but the general aspect of the plateaus, which are dry and cold in winter and in summer are swept by rainstorms and covered by occasional tufts of coarse grass, is barren and forbidding. they are also broken by great saline lagoons and dry salt basins. this region forms the argentine territory of los andes and is habitable in places. on the western slope the land descends gradually to the pacific, being broken into great basins, or terraces, by mountainous ridges in its higher elevations, widening out into gently-sloping sandy plains below, famous for their nitrate deposits, and terminating on the coast with sharply-sloping bluffs, having an elevation of 800 to 1500 ft., and looking from the sea like a range of flat-topped hills. this desolate region, which is rainless and absolutely barren, and was considered worthless for three and a half centuries, is now a treasure-house of mineral wealth, abounding in copper, silver, lead, nickel, cobalt, iron, nitrates and borax. it is occupied by many mining settlements, and includes some of the most productive copper and silver mines of the world. see l. darapsky, "zur geographic der puna de atacama," _zeits. ges. erdk. zu berlin_, 1899; g.e. church, "south america: an outline of its physical geography," _geographical journal_, 1901; john ball, _notes of a naturalist in south america_ (london, 1887); f. o'driscoll, "a journey to the north of the argentine republic," _geographical journal_, 1904. (a. j. l.)