Premium
Geometry, bed topography and drainage system structure of the haut glacier d'Arolla, Switzerland
Author(s) -
Sharp Martin,
Richards Keith,
Willis Ian,
Arnold Neil,
Nienow Peter,
Lawson Wendy,
Tison JeanLouis
Publication year - 1993
Publication title -
earth surface processes and landforms
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.294
H-Index - 127
eISSN - 1096-9837
pISSN - 0197-9337
DOI - 10.1002/esp.3290180608
Subject(s) - geology , meltwater , glacier , bedrock , geomorphology , glacier ice accumulation , glacier morphology , drainage system (geomorphology) , depth sounding , drainage , channel (broadcasting) , ice stream , hydrology (agriculture) , cryosphere , geotechnical engineering , climatology , oceanography , sea ice , ecology , engineering , electrical engineering , biology
As part of an integrated study of the hydrology, meltwater quality and dynamics of the Haut Glacier d'Arolla, Switzerland, the glacier's drainage network structure was determined from patterns of dye recovery in 342 injection experiments conducted from 47 moulins distributed widely across the glacier. This structure was compared with theoretical predictions based upon reconstructed patterns of water flow governed by (a) the subglacial hydraulic potential surface, and (b) the subglacial bedrock surface. These reconstructions were based on measurements of ice surface and bedrock topography obtained by a combination of ground survey and radio‐echo sounding techniques. The two reconstructions simulate the drainage system structures expected for (a) closed channels, in which water is pressurized by the overlying ice, and (b) gravity‐driven, open‐channel flow. The closed‐channel model provides the best fit to the observed structure, even though theoretical calculations suggest that, under summer discharge conditions, open‐channel flow may be widespread beneath the glacier. Possible reasons for this apparent discrepancy are discussed.