The purpose of these models is to show typical topographic forms and their relation to underlying geologic structures, They are not a representation of actual landscapes except in a very general way, However if a line were drawn from the state of Washington to the state of North Carolina most of these land forms would be encountered within a few hundred miles of either side of such a line, Great forces have been at work for hundreds of millions of years to shaped the crust of the earth, These forces are still at work and will continue as long as the earth exists, All geologic processes can be classified under three heads: Diastrophism Volcanism and Gradation, Model includes: 8 formed models and 1 guide, Made with the Best Quality Material with your child in mind, Top Quality Children"s Item, American Educational Products have a lead ship time of 21 days, SKU: AMED356