A Reconnaissance of Parts of Northwestern New Mexico and Northern Arizona

Front Cover
U.S. Government Printing Office, 1910 - Geology - 88 pages
 

Common terms and phrases

Popular passages

Page 59 - ... thickness of over forty feet which near the top contain bands of flags or sandstone impregnated with iron. Usually one of these layers at least is fossiliferous and has been termed the Gasteropod zone. Among the fossils so far identified in this bed are the following : Ostrea translucida, Exogyra 1 Farther to the westward this band reposes on the Dakota Sandstone or may perhaps be said to form a part of it.