Fossil seashells have been found in rock beds on land. what can you infer about how the area has changed

When we go to the beach one of the most exiting activities that we do is of course collect the best looking seashells. Now I have never seen seashells in another place other than the beach.

 My point in this entery that I have just mentioned is that where there is seeashells there is body of water. What those fossils mean is that that particular place whhere those seashells were once found means that maybe a very long whille back that place was onetime a body of water. Some natural dissaster came and that place doughtet and the water moved to some place else. 

My pleasure to help, over and out ;)