The Geology of Michigan 

 - Cranbrook Institute of Science 
 - DVD; 60 mins 
<br/><br/> Travel through billions of years of geologic history and discover the processes and events that created and continued to form the Great Lakes and the regions that border these remarkable freshwater bodies.  From salt deposits formed in shallow tropical seas to contnental glaciers to the roots of ancient mountains, the experience that is an Epedition through Deep time is the most comprehensive video resourse for experiencing and understanding one of our plantet's most extraordinary geologic landscapes