"Strain" refers to the changes in shape and size that occur during deformation. To determine how much strain has occurred, it's necessary to find objects of known original shape and size. The photographs on this page show examples of deformed objects of known original shape or size, that reveal the strain that has affected the rocks.
Deformed trilobite, Moydart Formation, Silurian Arisaig Group, Moydart Point, Nova Scotia, Canada.
Deformed pillow lavas, Twillick Point, Carmanville, Newfoundland, Canada.
Deformed Conglomerate: Proterozoic Purcell Supergroup, British Columbia, Canada