Geol/Nats107

Illustrations

History

Iapetus

Precambrian

Depth of erosion of mountains

Grain size through time

Upper Cambrian

Middle Ordovician

Upper Ordovician

Middle Silurian

Middle Pennsylvanian

Start of Cyclotherms

Tectonic activity through time

Paleozoic History of Eastern U. S.

Dinosaur sizes

Last Modified July 15, 1997 RD