The processes of sedimentation in Lake C2, like other meromictic lakes with clastic sediment inputs, are strongly controlled by the density stratification. Primarily, the stratification of the water column allows for sedment to be broadly dispersed across the lake basin rather than being mixed and deposited in the delta proximal zone and also prohibits disturbance of the sediments once deposited because of the anoxia below the chemocline.
Suspended sediment transport closely parallels the suspended sediment concentrations in the main inlet stream (Hardy, 1996). Analysis of sediment trap yields in the delta proximal zone of the lake in 1992 shows that the bulk of the suspended sediment is transported in a few distinct events, although trace amounts in the traps reflected the diurnal hydrologic inputs.
The two main events in which sediment is contributed to the lake are the main spring freshet and a late summer pulse associated with a heavy precipitation event and subsequent snowmelt. During the early season freshet, cold meltwater enters the lake and disperses across the prodelta zone as a sediment plume. Once the outlet of the lake opens, the plume is drawn on a trajectory towards the outlet. During this period, because of the density contrast between the inflowing cold meltwater and sediment and the saline lake, the sediment is transported in the uppermost zone of the water column as an overflow.
The second major pulse of sediment in the summer of 1992 rejuvenated the sediment plume and spread widely across the central lake basin. Sediment was transported as both overflows and interflows as the meltwater and sediment travelled across the chemocline at a depth of approximately 15 to 18 meters. "Event traps"yielded the highest sediment catch in 1992 in response to this major discharge event.