Geologists divide the iron-bearing rocks of the eastern Mesabi Iron Range into several layers: its four main divisions from the top down are named the Upper Slaty, Upper Cherty, Lower Slaty and Lower Cherty.
The four main divisions from the top down are the Upper Slaty, Upper Cherty, Lower Slaty and Lower Cherty. Geologists divide the iron-bearing rocks of the eastern Mesabi Iron Range into several layers.
Geologists divide the iron-bearing rocks of the eastern Mesabi Iron Range into several layers. The four main divisions from the top down are the Upper Slaty, Upper Cherty, Lower Slaty and Lower Cherty.
Geologists divide the iron-bearing rocks of the eastern Mesabi Iron Range into several layers. The four main divisions from the top down are the Upper Slaty, Upper Cherty, Lower Slaty and Lower Cherty.