CREVASSE DETECTION IN GLACIERS OF SOUTHERN CHILE AND ANTARCTICA BY MEANS OF GROUND PENETRATING RADAR
Author
Araya, LuisBunster Weitzmann, Claudio Moises
Casassa Rogazinski, Gino
Mella Pineda, Ronald Andres
Neira, Guillermo
Ordenes Silva, Fernando Ruben
Rivera Ibañez, Sergio Andres
Zamora Maric, Rodrigo Eduardo
Abstract
Detection of crevasses is critical for safe travelling on glaciers. Here we present the use of a Ground Penetrating Radar (GPR) for crevasse detection. Experiments were made in temperate ice on Glaciar Mocho, Volcán Mocho-Choshuenco, southern Chile (39°25'S) and in cold ice in East Antarctica (87°30'S). In southern Chile the radar was hand-carried 1.2 m in front of the operator who was walking over the glacier at a speed of ~0.5 m s -1 , while in...
Ver más
Detection of crevasses is critical for safe travelling on glaciers. Here we present the use of a Ground Penetrating Radar (GPR) for crevasse detection. Experiments were made in temperate ice on Glaciar Mocho, Volcán Mocho-Choshuenco, southern Chile (39°25'S) and in cold ice in East Antarctica (87°30'S). In southern Chile the radar was hand-carried 1.2 m in front of the operator who was walking over the glacier at a speed of ~0.5 m s -1 , while in Antarctica it was mounted on a 7 m-long rod in front of a tractor convoy travelling at a speed of ~2 m s -1 . In both geographical sites profiles were made perpendicularly to crevasses ranging in width from 0.1 m to 1.0 m. Buried crevasses clearly show as apexes of diffraction hyperbolae, which could be detected down to a depth of 15 m. Show as discontinuities in the firn stratigraphy which have a width equal to the crevasse width, and associated diffraction hyperbolae to each side of the crevasse. The GPR proved to be a valuable tool for detecting crevasses, allowing for a reaction time of ~9 s (equivalent to ~4.5 m on the ground) in the case of the hand-carried system and ~5 s (or ~10 m on the ground) for the tractor system.
Ver menos
Book's title
GLACIER MASS BALANCE CHANGES AND MELTWATER DISCHARGE
Publication date of the book
2007Start page
153
End page
162