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Experiments on the origin of kettle-hales : comments on the paper by Dr J. K. Maizels

Dr Reference MaizelsJ. K. Maizels' (1977) paper on laboratory simulations of kettle-hole development was a reminder of "mini-kettle-hole" formation observed in July 1958. Figure 1 shows the small cavities in various stages of development, each related to the melting rate of partially buried ice blocks.

Fig. 1. "Mini-kettle-holes" formed by the ablation of ice stranded on the basin floor of Tulsequah Lake 3 days after it had drained.

The circumstances under which these features developed were rather unusual. Figure 1 shows part of the basin floor of ice-dammed Tulsequah Lake, British Columbia. Approximately 72 h earlier, the lake had drained catastrophically (Reference MarcusMarcus, 1960). Icebergs derived from the Tulsequah Glacier ice dam were left perched about the slopes and floor of the emptied basin; many small pieces of ice were similarly stranded. Meanwhile, streams flowing into the lake dropped to the newly established base level, formed depositional fans along the lake floor and partially or fully covered the smaller ice blocks with sediments. Local equilibrium was roughly established within 2 days. Ablation produced the micro-landscape shown in Figure 1 by the end of the third day.