THE ADIRONDACK MOUNTAINS 



53 



Fig. 9 Geologic and topographic map of the vicinity of Wells show- 

 ing the relations of various rock formations and several conspicuous 

 faults. Contour interval: lOO feet. Positions of faults represented by 

 heavy black lines. Gv=Grenville strata ; Sy=syenite ; Gr=granite ; Gsg-^= 

 Grenville-syenite-granite mixed rocks ; black areas^gabbro or diabase ; 

 P;=Potsdam sandstone ; T=Theresa formation ; L=Little Falls lime- 

 stone : 0=Lower Trenton limestone; Oc=Canajoharie (Trenton) shale; 

 Pu^Paleozoic strata. Geology by W. J. Miller. 



