Non-glacial sculpted bedrock erosional forms or S-forms ranging in size from a few centimeters to a few metres are locally well preserved in the region, mainly on fine-grained, hard lithologies such as volcanic rocks of greenstone belts. They are commonly associated with adjacent or ubiquitous parallel striations and other erosional glacial ice flow indicators. The features are thought to originate from fluvial erosional processes associated with subglacial meltwater under high pressure. Their significance to drift composition and glacial dispersal is unknown.

S-Form	Photo Description
Furrows larger image [JPEG, 48.6 kb, 303 X 474, notice]	Locally, bedrock surfaces exhibit elongate grooves, commonly curved or branching in plan view, as shown here. The furrows are parallel to the flow direction, which in this photo is from top to bottom.
Open spindle flute larger image [JPEG, 30.7 kb, 301 X 466, notice]	Spindle flutes are depressions in the bedrock with a pointed end, oriented upflow, which broadens downflow to a smooth ramp. Edges are sharp. The flow direction is toward the top of the photo. Striations in the spindle are slightly curved and conform to the shape of the feature. They are approximately parallel to those on the adjacent bedrock surface.
Superimposed spindle flutes larger image [JPEG, 51.2 kb, 591 X 380, notice]	Spindle flutes are well preserved on mafic volcanic rocks. The flute orientations indicate flow toward the top of the photo, slighlty oblique to stration trends. Both the fluted and adjacent bedrock surfaces are striated.
Furrows, spindle flutes and cavettos larger image [JPEG, 66.9 kb, 592 X 384, notice]	Complex S-forms are accentuated by variation in bedrock composition.