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Ice-push action causes considerable shore and vegetation damage on lakes located 10–40 km southeast of Schefferville in central Quebec – Labrador. The damage occurs mainly on shores of large lakes; on small ones the damage is slight. In the spring the wind-driven ice thrusting up on the shores moves shore material, even quite large stones, and forms fine ice-push ridges. It also uproots trees and shifts them far landward. The ice-made features on shores of large lakes are common: they occur on 46% of the shores. In addition, there is slight vegetation damage on 32% of the shores; only 22% of the shores lack signs of ice push. Ice push is a major process moulding the shorelines of these lakes.

The development of beach cusps was observed on Mont‐St‐Pierre beach on the southern shore of the St Lawrence estuary on the Gaspé peninsula, in July 1979. Local observations and sediment analyses showed that the cusp material originated from a beach ridge located in the upper part of the tidal area. The initial stage in the formation of cusps was the breaching of this beach ridge by the swash. Material transported by the swash and backwash formed the cusp horns. No cusps were observed to develop on the western part of the beach where the beach ridge was not breached by the swash. Le développement des croissants de plage a été observé sur la plage de Mont‐St‐Pierre, la céte méridionale de l'estuaire du Saint‐Laurent, sur peninsule de la Gaspésie, en juillet 1979. Les observations faites sur l'aire de recherche et les analyses skdimentaires ont révélé que les matériaux des croissants de plage étaient essentiellement originaires d'une crtte de plage qui se trouvait dans la partie supérieure de la zone de rnarée. La formation des croissants de plage a commencé par la rupture de la crtte de plage que les bas‐fonds avaient causées. Ces matkriaux transportés par les bas‐fonds et les bas‐fonds revenants ont produit les parties pointues des croissants. Aucun croissant de plage ne s’était produit dans la région ouest de la plage ou les bas‐fonds n'ebrkchaient pas la crtte de plage.

The morphometry of trondhjemite pebbles and cobbles from till and esker material and from moraine-shore and esker-shore material was studied in the Airisto area, SW Finnish Archipelago. The maximum projection roundness, sphericity, and oblate-prolateness were measured on 2000 pebbles and cobbles in the 16-256 mm size range. Wave energy was low at the study sites, which owing to land uplift rise beyond the reach of littoral forces in a relatively short time (the upper beach over a period of about 800 years). Of the three indices, roundness shows the greatest variation, from 0.30 to 0.72. The oblate-prolate index also showed significant variations (-0.66 - + 1.43). The poorest indicator, but not entirely useless as a discriminatory tool, is the sphericity index, which showed least change (0.69 - 0.78). The increase in roundness and decrease in oblate-prolate index are predominantly the results of abrasion caused by the sliding and rolling of pebbles and cobbles to and fro over sand and gravel in the breaker and swash zones. On mixed gravel-cobble shores from till pebbles (16-64 mm) were most disc-like while cobbles (64-128 mm) were most disc-like on esker shores.

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