HR: 1400h
AN: PP43C-15    [Abstracts]
TI: Natural Environmental Hazards Reflected in High-Altitude Patagonian Lake Sediments (Lake Caviahue, Argentina)
AU: * Mueller, A
EM: Anne.Muller@gmx.de
AF: UFZ Centre for Environmental Research, Brueckstr. 3a, Magdeburg, Germany
AU: Pirrung, M
AF: Institut fuer Geowissenschaften, Friedrich-Schiller Universitaet Jena, Burgweg 11, Jena, 07749, Germany
AU: Scharf, B
AF: UFZ Centre for Environmental Research, Brueckstr. 3a, Magdeburg, Germany
AU: von Tuempling, W
AF: UFZ Centre for Environmental Research, Brueckstr. 3a, Magdeburg, Germany
AB: Two 6-m long sediment cores drilled in the two basins of Lake Caviahue give new evidence of the impact of natural hazards such as ash fallouts linked to nearby volcanic eruptions in the ecologically sensitive environment of the high-altitude region of the Argentinan Patagonian Andes. The two cores show distinct signals of changes in autochthonous productivity and terrigenous input into the lake from ash fallout, river load and shore erosion. Multiproxy records of the sediments indicate whether these changes can be related to volcanic activity. High values of magnetic susceptibility in the cores reflect periods of basaltic ash fallouts during eruptions of the nearby Copahue volcano. The southern basin is located in the prevalent direction of ash fallouts and has been affected by these volcanic inputs more intensely than the northern basin of the lake. In contrast, sedimentation and authochthonous productivity in the northern basin are strongly affected by fluvial inputs such as suspended river load and acidic stream waters.
DE: 0458 Limnology (1845, 4239, 4942)
DE: 0468 Natural hazards
DE: 1599 General or miscellaneous
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Joint Assembly