Geology and geochemistry of the Atacama Desert

Abstract

The Atacama Desert, the driest of its kind on Earth, hosts a number of unique geological and geochemical features that make it unlike any other environment on the planet. Considering its location on the western border of South America, between 17 and 28 °S, its climate has been characterized as arid to hyperarid for at least the past 10 million years. Notably dry climatic conditions of the Atacama Desert have been related to uplift of the Andes and are believed to have played an important role in the development of the most distinctive features of this desert, including: (i) nitrates and iodine deposits in the Central Depression, (ii) secondary enrichment in porphyry copper deposits in the Precordillera, (iii) Li enrichment in salt flats of the Altiplano, and (iv) life in extreme habitats. The geology and physiography of the Atacama Desert have been largely shaped by the convergent margin present since the Mesozoic era. The geochemistry of surface materials is related to rock geochemistry (Co, Cr, Fe, Mn, V, and Zn), salt flats, and evaporite compositions in endorheic basins (As, B, and Li), in addition to anthropogenic activities (Cu, Mo, and Pb). The composition of surface water is highly variable, nonetheless in general it presents a circumneutral pH with higher conductivity and total dissolved solids in brines. Major water constituents, with the exception of HCO, are generally related to the increase of salinity, and despite the fact that trace elements are not well-documented, surface waters of the Atacama Desert are enriched in As, B, and Li when compared to the average respective concentrations in rivers worldwide.

Nitrates as a Potential N Supply for Microbial Ecosystems in a Hyperarid Mars Analog System

“…TZ-5 soils are affected by Quaternary and Cretaceous sedimentary rocks, and Paleozoic-Mesozoic and Mesozoic-Cenozoic intrusives. Finally, TZ-6 soils are affected by Quaternary and Cretaceous sedimentary rocks, as well as Mesozoic-Cenozoic intrusives [52,53].…”

Insights into the diversity and survival strategies of soil bacterial isolates from the Atacama Desert

“…During the year, the air temperature ranges from -6 o C (21.2 o F) to 38 o C (100.4 o F) (Azua-Bustos, Urrejola, and Vicuna 2012; Bull et al 2018). The Atacama Desert contains many salt flats, which contributes to a high salt content and a high density of minerals including nitrates, iodates, boron, lithium, and copper deposits (Tapia et al 2018). The Atacama Desert has been considered "a prime example of the extremobiosphere" (Bull et al 2018).…”

“…It is likely that the soil color is given by the richness of transition metals such as Copper, Nickel, Cobalt, Iron, and Manganese in association with alkali metals such as Lithium, Sodium, and Potassium. All these salts are known to exist in the soils of the Atacama (Tapia et al 2018). The green soil is believed to have an enrichment of magnesium, cobalt, and sulfur, while the red soil contains an enrichment of iron, and the white soil an enrichment of sodium chloride and calcium from shell erosion, among multiple other metals and minerals.…”

Vanadium Pentaoksida (V2O5) : Termodinamika Molecular dan Interaksi Ion dalam Larutan

“…Ketika pelarut diuapkan, ion tidak ikut menguap, tetapi tetap berada di dalam larutan yang tertinggal , dan bila sudah cukup pekat terjadilah nukleasi (154)(155)(156) dan mengkristal menjadi senyawa ionic. Proses ini dapat dinamakan dengan cara pembentukan mineral evaporit (157)(158)(159)(160)(161)(162). Pada vanadium pentaoksida memiliki titik lebur (163)(164)(165)(166)…”