photos from http://www.stmarys.ca/academic/science/geology/pub/8mechanical.html
cycle. Most substances expand when hot or cooled and water is one of them. Water can expand at temperatures that are 4 degrees Celsius down to negative 20 degress Celsius. This expansion is the cause of water pipes bursting in the winter when it is too cold. Rocks have crevices that gets filled with water, in these crevices there are joints that have cracks that were caused by plate tectonics. Frost wedging occurs in climates that are cool all year around
and freezing and thawing occurs constantly in most parts of Atlantic
Canada
East edge in Mt. Brewer in Sierra sharp edge boulders produced by frost action
http://www.geosci.unc.edu/faculty/glazner/Images/Weathering/weathering.html
