Frugone-Álvarez, M., et al. (2017), A 7000-year high-resolution lake sediment record from coastal central Chile (Lago Vichuquén, 34°S): implications for past sea level and environmental variability, Journal of Quaternary Science, n/a-n/a, doi: 10.1002/jqs.2936.
Abstract
We present a 7-ka environmental reconstruction based on sedimentological and geochemical data from Lago Vichuquén, a coastal eutrophic lake in central Chile (34°48'S, 72°03' W, 4?m a.s.l.). A relatively shallow and restricted marine environment with low productivity, high detrital input and dominant anoxic conditions in the Vichuquén Basin occurred from 7.0 to 6.5?cal ka BP. Rapid onset of a Holocene marine transgression at 6.5?cal ka BP favoured deeper and more biologically productive environments that existed until 2.8 cal ka BP. Bioproductivity changes during the mid-Holocene (6.5–4.2?cal ka BP) were related to upwelling dynamics controlled by the intensity of the South-east Pacific Anticyclone (SPA). Periods with lower organic productivity and dominant anoxic conditions reflect an increased intensity of SPA (increased upwelling) and decreased precipitation. A shift at ~4.0?cal ka BP reflects the onset of modern Southern Westerly Winds and El Niño-Southern Oscillation patterns. Tectonic uplifting and geormorphological activity (dune advancement) are possible reasons behind the Vichuquén Basin closure at ~1.2?cal ka BP, leading to a low bioproductivity lacustrine environment which has developed until the present.
