Tides and lake-level variations in the great Patagonian lakes: Observations, modelling and geophysical implications.

MARDERWALD ERIC; HORMAECHEA JOSE LUIS; RICHTER ANDREAS; GROH ANDREAS; HORWATH MARTIN

Vienna

Congreso; EGU General Assembly 2016; 2016

European Geosciences Union

In Patagonia, the glacial-isostatic adjustment (GIA) to past ice-mass changes (Ivins & James 2004; Klemann etal. 2007) is of particular interest in the context of the determination of the complex regional rheology relatedto plate subduction in a triple-junction constellation. To further complicate the situation, GIA is overlaid withload deformation not only due to present ice mass changes but also due to water-level changes in the lakessurrounding the icefields and the ocean surrounding Patagonia. These elastic deformations affect the determinationof glacial-isostatic uplift rates from GPS observations (Dietrich et al. 2010; Lange et al. 2014). Observations oflake tides and their comparison with the theoretical tidal signal have been used previously to validate predictionsof ocean tidal loading and have revealed regional deviations from conventional global elastic earth models (Richteret al. 2009). In this work we investigate the tides and lake-level variations in Lago Argentino, Lago Viedma, LagoSan Martín/O?Higgins and Lago Buenos Aires/General Carrera. This allows us to test, among other things, thevalidity of tidal loading models.