50 MHz helicopter-borne radar data for determination of glacier thermal regime in the central Chilean Andes

• Published in: Annals of Glaciology
• Main Authors: Gacitúa, Guisella, Uribe, José A., Wilson, Ryan, Loriaux, Thomas, Hernández, Jorge, Rivera Ibáñez, Sergio
• Format: Article in Journal/Newspaper
• Language: English
• Published: Int Glaciol Soc 2015
• Subjects: Aerogeophysical measurements; Applied glaciology; Basal ice; Glacial geomorphology; Isi; Olivares; Annals of Glaciology
• Online Access: https://doi.org/10.3189/2015AoG70A953; https://repositorio.uchile.cl/handle/2250/135590

Artículo de publicación ISI Despite their importance as freshwater reservoirs for downstream river systems, few glaciers in central Chile have been comprehensively surveyed. This study presents ground-penetrating radar (GPR) and field-based observations for characterizing the englacial and basal conditions of Glaciar Olivares Alfa (33°110 S, 70°130 W), central Chilean Andes. Using a 50MHz radar mounted onto a helicopter platform, data were collected covering large portions of the glacier accumulation and ablation zones. The radar data revealed boundaries of a temperate-ice layer at the base of the eastern body of Glaciar Olivares Alfa which appears to be covered by colder ice that extends throughout large parts of the glacier. The thickness of the temperate ice layer is highly variable across the glacier, being on average 40% of the total ice thickness. Radar data analyses reveal regions of cold ice at the bottom/ base of the glacier and also patterns of highly saturated sediments beneath the glacier. Using GPR data, this study represents the most exhaustive analysis of glacier ice structure performed in the central Chilean Andes. The results will enable improved estimations of the glacier’s mass balance and ice dynamics, helping us to understand its further development and its impact on water availability. Basal Financing Program of the Scientific and Technological National Commission of Chile (CONICYT) CODELCO Andina Division mining company Anglo American Chile mining company