Dynamic effects of "sediment-laden underflows" on lake sedimentation are documented. using field data obtained in glacier-fed Peyto Lake. Canada during the glacier-melting period (June-August) of 1987. "Sediment-laden underflows" are here referred to bottom currents flowing continuously on an undulated bottom bed of lake with keeping relatively high suspended sediment concentration. The dynamic behav· ior of the sediment-laden underflows in Peyto Lake is outlined by some observational results of flow velocity. water temperature and sediment concentration. Sediment sorting processes of the sediment-laden underflows are specified by grain size distribu· tions of the sediment trapped near the bottom. The fine sediment transported by the underflows probably sinks as non-flocculated. discrete grains within the bottom water of almost no salinity and low sediment concentration « -80 mg/I). because the sediment is almost dolomitic. thus including little cohesive clay mineral. Sedimentation rates estimated for the underflows. the delta progradation and overflows and/or interflows account for 61%. 32% and 7% of the overall sedimenta· tion. respectively. and offer the possible life span of 586 yrs.
[1]
Kazuhisa Chikita,et al.
Sedimentation by river‐induced turbidity currents: field measurements and interpretation
,
1990
.
[2]
F. Weirich.
The record of density-induced underflows in a glacial lake
,
1986
.
[3]
R. Gilbert.
Sedimentation in Lillooet Lake, British Columbia
,
1975
.
[4]
R. Folk,et al.
Brazos River bar [Texas]; a study in the significance of grain size parameters
,
1957
.
[5]
D. Inman,et al.
Measures for describing the size distribution of sediments
,
1952
.
[6]
知北 和久,et al.
Dynamic sedimentation processes in a Glacier-Fed Lake, Peyto Lake, Alberta, Canada.
,
1991
.
[7]
G. Ashley,et al.
Proglacial Lacustrine Environment
,
1985
.