CARACTERIZACIÓN Y CORRELACIÓN DE NIVELES VOLCÁNICOS IDENTIFICADOS EN LA LAG. PORTEZUELO (37°S) EN LOS ÚLTIMOS 200 AÑOS

VILLA S.; DAGA R.; - CASELLI, A.T.

Tucuman

Congreso; XX Congreso Geológico Argentino; 2017

Asociación Geológica Argentina

In areas characterized by active and intense volcanism, fragments from different sources can be incorporated to the sediment at the same time, as well as different types of particles can be formed during a single event. This work presents morphological, textural and compositional analyses of 9 tephra layers from a lacustrine sedimentary sequence from Portezuelo lake, with the objective to correlate the volcanic layers with Copahue or others volcanos from the Southern Volcanic Zone for the last 200 years. The first results allowed to associate three tephras to the Vn. Copahue, while other three microtephras have acidic compositions without a clear source up to the moment. Other three microtephras showed bimodal composition which may have mix of particles; in this case the macroscopic characterization included materials of different composition.