SMITHSONIAN MISCELLANEOUS COLLECTIONS 



L-nconfonnablc contact on line (Aa) between Archean (/ = V-'}?" ,^^.' \"'. 7 ,-ests unconf' 

 le of view on line {Arc). In center and left side on line Ac the Cambrian (/ ^„gel ^f. 



Locality: North side of Grand Canyon of Colorado River, Arizona, t)elow ^1^ ^.r„sion a" ' 

 One of the finest of the exposures showing the pre-Canibrian surface giaacu_ ^^^ 

 Muav limestone (.1/) fonn terraces up to base of Carboniferous Red Wall limes-iu 



ikian (u74^,1 Cambrian (r=:Tapeats sandstone) and Archean (T- Vishnu series) on right 

 th „r i:;"Kar_ series). 



e two higher formations of Cambrian Bright Angel shales (BA) and 



'.."louth of Bi« r 

 ■^'«""kian form" iSr" 



