U. S. OEOLOCirAI. SI'I'.VEV 



rT!OFESSIO\AL rAI'EI! 139 I'l.ATi: X\ l\ 





,1. BA,\K (IK WASH WEMi W OOLSKV 'I'ANK, GILA UENU MUUNTAINS. MMUCOI'A CUtM'\. Al'.l/. 

 An i-\jH)siin^ {ft tilh-ii 'I'crliary s;iinlslune uncont'ornuihly overlain by tilled Qiialernary gravel. 





'ij; «?*»'" 



Ji. Wooi.SliY TANK. LilLA BEND MOUNTAINS, MARICOI'A COUNTY, ARIZ. 

 Coarse gravel willi calearcous ceineiil, of Quaternary age, resting on the surfai^e ol'T'ertiary basall. 



