Rockglaciers are landforms related to ice-rich permafrost creep and represent a substantial reservoir of groundwater in the alpine region. Rockglacier lakes can occur when permafrost-ice meltwater released from rockglaciers, snowmelt, rain and groundwater find the geomorphologic conditions to be collected in an impermeable depression. This depression can be filled with fine-grained sediments (∅<1/16 mm) from at least three sources: 1) the dust contained in the snow covering the lake during winter, 2) the solid fraction of the runoff and meltwater from the rockglacier and 3) the runoff or the wind transport from the surrounding areas. Fine sediment volumes, bedding and typology offer large amount of information for interpreting the past and ongoing biological and abiotic processes in the catchment. In order to estimate the fine sediment volumes and plan a coring campaign in the Col d’Olen Rockglacier Lake (Aosta Valley, Italy) we performed waterborne GPR surveys with both 200 and 500 MHz antennas. After data processing we obtained the bathymetry of the top and the bottom of the fine sediments. Within the fine sediments unit we also found a discontinuity whose meaning will be investigated with a planned coring located in the zone with the maximum sediment thickness.

A waterborne GPR survey to estimate fine sediments volume and find optimum core location in a rockglacier lake / Sambuelli, Luigi; Nicola, Colombo; Marco, Giardino; Danilo, Godone. - CD-ROM. - (2015). ((Intervento presentato al convegno 21st European Meeting on Environmental and Engineering Geophysics tenutosi a Turin - Italy nel 7-9 September.

A waterborne GPR survey to estimate fine sediments volume and find optimum core location in a rockglacier lake

SAMBUELLI, Luigi;
2015

Abstract

Rockglaciers are landforms related to ice-rich permafrost creep and represent a substantial reservoir of groundwater in the alpine region. Rockglacier lakes can occur when permafrost-ice meltwater released from rockglaciers, snowmelt, rain and groundwater find the geomorphologic conditions to be collected in an impermeable depression. This depression can be filled with fine-grained sediments (∅<1/16 mm) from at least three sources: 1) the dust contained in the snow covering the lake during winter, 2) the solid fraction of the runoff and meltwater from the rockglacier and 3) the runoff or the wind transport from the surrounding areas. Fine sediment volumes, bedding and typology offer large amount of information for interpreting the past and ongoing biological and abiotic processes in the catchment. In order to estimate the fine sediment volumes and plan a coring campaign in the Col d’Olen Rockglacier Lake (Aosta Valley, Italy) we performed waterborne GPR surveys with both 200 and 500 MHz antennas. After data processing we obtained the bathymetry of the top and the bottom of the fine sediments. Within the fine sediments unit we also found a discontinuity whose meaning will be investigated with a planned coring located in the zone with the maximum sediment thickness.
File in questo prodotto:
File Dimensione Formato  
We 21P1 18LAKE.pdf

non disponibili

Tipologia: 2. Post-print / Author's Accepted Manuscript
Licenza: Non Pubblico - Accesso privato/ristretto
Dimensione 3.88 MB
Formato Adobe PDF
3.88 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11583/2617568
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo