Glacial grooves, East Sister Island, Lake Erie, Ontario, Canada. The glacial grooves in this photo are roughly 385 million years old, and were created from the gouging action of ice flowing in the Lake Erie basin. Recent freeze-thaw activity has produced significant frost heaves, or raised blocks, within and beside the glacial grooves. —Source: Natural Resources Canada. Photographer: R.N. McNeely. Copyright Terrain Sciences Division, Geological Survey of Canada.
Lateral glacial abrasion on rock wall, New Zealand. Lateral glacial abrasion has smoothed this metamorphic rock. The flowlines indicate a downward direction. —Source: Tom Lowell's Glacier Image Database, University of Cincinnati.
Striated Graywackie, Yale Glacier, Alaska. 1997. Parallel striations and bedrock fracture trends (across the left side of the image) are clearly visible in this photo. —Source: Tom Lowell's Glacier Image Database, University of Cincinnati.
The glacial character of the surface shield at the Strait of Belle Isle is the effect of an ancient ice age about 1 billion years ago. The surface was preserved under a layer of sedimentary rocks.