Chronology, stratigraphy and hydrological modelling of extensive wetlands and paleolakes in the hyperarid core of the Atacama Desert during the late quaternary

QUATERNARY SCIENCE REVIEWS

卷:197

Article

Pfeiffer, Marco^1,2  Latorre, Claudio^3,4,5  Santoro, Calogero M.⁶  Gayo, Eugenia M.^7,8  Rojas, Rodrigo⁹  Laura Carrevedo, Maria⁵  McRostie, Virginia B.^4,10  Finstad, Kari M.¹¹  Heimsath, Arjun¹²  Jungers, Matthew C.¹³  De Pol-Holz, Ricardo^8,14  Amundson, Ronald¹ 

[1] Univ Calif Berkeley, Dept Environm Sci Policy & Management, 130 Mulford Hall, Berkeley, CA 94720 USA

[2] Univ Chile, Fac Ciencias Agron, Dept Ingn & Suelos, Santiago 11315, Chile

[3] Pontificia Univ Catolica Chile, Dept Ecol, Santiago, Chile

[4] Pontificia Univ Catolica Chile, Ctr UC Desierto Atacama, Santiago, Chile

[5] IEB, Santiago, Chile

[6] Univ Tarapaca, Inst Alta Invest, Antofagasta 1520,Casilla 6-D, Arica, Chile

[7] Univ Concepcion, Fac Ciencias Nat & Oceanog, Dept Oceanog, Lab Stable Isotope Biogeochem, Casilla 160-C, Concepcion, Chile

[8] Ctr Climate & Resilience Res CR2, Santiago, Chile

[9] CSIRO Land & Water, POB 2583, Brisbane, Qld 4001, Australia

[10] Pontificia Univ Catolica Chile, Dept Antropol, Santiago, Chile

[11] Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA

[12] Arizona State Univ, Sch Earth & Space Explorat, ISTB4,Room 795,781 E Terrace Rd, Tempe, AZ 85287 USA

[13] Denison Coll, Dept Geosci, 306 Olin Sci Hall,100 West Coll St, Granville, OH 43023 USA

[14] Univ Magallanes, GAIA Antartica, Punta Arenas, Chile

关键词: Atacama desert;    Hyperaridity;    Wetlands;    Late quaternary;    Paleogeography;    South America;    Sedimentology;   

DOI  :  10.1016/j.quascirev.2018.08.001

来源: Elsevier

【 摘 要 】

The halite-encrusted salt pans (salars) present at low elevations in the hyperarid core of the Atacama Desert in northern Chile are unique features of one of the driest and possibly oldest deserts on Earth. Here we show that these landscapes were shallow freshwater lakes and wetlands during the last glacial period and formed periodically between similar to 46.9 ka and 7.7 ka. The moisture appears to have been sourced from increased Andean runoff and most of our chronologies for these deposits were coeval with the Central Andean Pluvial Event (17.5-14.2 ka and 13.8-9.7 ka), but we also find evidence for older as well as slightly younger wet phases. These environments supported a diverse hygrophytic-halophytic vegetation, as well as an array of diatoms and gastropods. Using a regional hydrological model, we estimate that recharge rates from 1.5 to 4 times present were required to activate and maintain these wetlands in the past. Activation in the late Pleistocene was part of a regional enhancement of water resources, extending from the Andes, downstream and through riparian corridors, to the lowest and most arid portions of the desert itself. This fundamentally unique environment was encountered by the earliest human explorers in the region, and most likely facilitated migration and encampments on a landscape that at present lacks macroscopic life on its surface. (C) 2018 Elsevier Ltd. All rights reserved.

【 授权许可】

Free