1,Qa,18,Alluvium,Holocene 2,O,0,none,unknown 3,Qf,112,Alluvial-fan deposits,Holocene and upper Pleistocene 22,Aqf,14,Quartzofeldspathic gneiss,Archean 23,Aa,425,Amphibolite,Archean 24,Asg,300,Interlayered schist and gneiss,Archean 27,Ag,725,Older gneiss and schist,Archean 36,Qg,24,Terrace-gravel deposits,Upper Pleistocene 37,QTb,151,Basin-fill deposits,Pleistocene and Pliocene? 38,Aam,172,Amphibolite assemblage,Archean 39,Aag,472,Aluminous gneiss and schist,Archean 40,Aq,741,Quartzite and quartz-mica schist,Archean