Glacial sediment production and development of hydro-electric power in glacierized areas

摘要: by Jim Bogen (Glaciology Section, Norwegian Water Resources and Energy Administration, P.O. Box 5091, Majorstua, N-0301 Oslo 3, Norway) ABSTRACT This paper discusses the results of a sediment­monitoring programme carried out in connection with hydro-electric power development plans river basins surrounding Jostedalsbreen ice cap Norway. Whereas highest suspended-sediment transport rates occur during years several flash-flood events, bed load is more dependent upon duration large magnitude flood events. Bed-load has been obtained from annual measurements deltaic growth small lakes at front glaciers. During 1968-86, mean ratio to total amounted 0.30-0.50% load, but floods this decreased. The suspended sediment yield glaciers ranges 100 tonnes km2 a-I 1300 a-I. Valley cause erosion rates, exception cirque glacier, Trollbergdalsbreen, which thought be soft glacier. investigation undertaken involved monitoring volume sediments, together size distribution, mineralogy shape grains. In general, valley supply sand than smaller glaciers, whereas particles fine silt-size almost all are angular shape. Methods comparing abrasive capacity various intakes plant discussed. Long-term was investigated studies varves rythmites cores glacier-fed lakes. INTRODUCTION last few years, glacier areas Norway have developed for power. sediment-monitoring on western side, Breheimen-Stryn Project, involve diversions water 32 (Fig.