Western and south-central parts of quadrangle
    Intrusive rocks
.79
Tdl    Diabase and lamprophyre dikes
.9
Trd    Rhyolite dikes
.89
Tri    Rhyolite stock
.70
Td     Dikes
.9
Tdu    Tertiary dikes, undivided
.13
Tg     Granite
.59
Tdc    Diorite complex
.15
Tgp    Gray porphyry

    Extrusive rocks
.0
Twt    Welded tuff of Obsidian
.90
Tva    Andesite
.91
Tvr    Rhyolite flows
.29
Tcv    Challis volcanic group, undivided

    CRETACEOUS INTRUSIVE ROCKS
.92
Ki     Granitic rocks of Idaho batholith, undivided
.93
Klg    Leucocratic granite
.94
Kg     Muscovite-biotite granodiorite and granite
.95
Kgd    Biotite granodiorite
.96
Kgds   Sphene-enriched biotite granodiorite
.97
Kgdp   Porphyritic biotite granodiorite and granite
.98
Kgdh   Hornblende-biotite granodiorite
.99
Kt     Tonalite and granodiorite
.100
Kim    Mixed rock units

    JURASSIC INTRUSIVE ROCKS
.101
Jg     Gabbro

    PALEOZOIC SEDIMENTARY ROCKS
.102
Pg     Grand Prize Formation (Lower Permian)

       Wood River Formation
.103
PIPw     Upper part (Lower Permian and Upper 
          Pennsylvanian)
.104
IPwl     Lower part (Upper to Middle Pennsylvanian)
.105
Pzsr   Salmon River assemblage (Paleozoic)
.106
Msuc   Surrett Canyon and South Creek Formations,
        undivided (Upper Mississippian)
.107
Msp    Scott Peak Formation (Upper Mississippian)
.0
Mmc    Middle Canyon Formation (Upper Mississippian 
        and Lower Mississippian)
.108
Mw     White Knob Limestone (Upper Mississippian)
.109
Mmg    McGowan Creek Formation (Lower Mississippian)
.110
Mcb    Copper Basin Formation, lower part 
        (Lower Mississippian)
.111
Dgj    Grand View and Jefferson Dolomites, undivided 
.112
Dg     Grand View Dolomite (Upper Devonian)
.113
Dj     Jefferson Dolomite (Upper and Middle Devonian)
.114
Dab    Informal units B (Middle? and Lower Devonian) 
        and A (Lower Devonian) of Hays and others (1978, 
        1980) and Beartooth Butte Formation (Lower 
        Devonian), undivided
.115
Sl     Laketown Dolomite (Silurian)
.116
Srm    Roberts Mountains Formation (Silurian)
.117
Op     Black, carbonaceous, graptolite-bearing shale and 
        argillite (Ordovician)
.118
Ose    Saturday Mountain Formation, Kinnikinic Quartzite
        and Ella Dolomite, undivided (Ordovician)
.119
Oc     Upper carbonate unit (Ordovician)
.120
OCrr   Siltstone, sandy siltstone and quartzite of Rob
        Roy mine area (Ordovician? or Cambrian?)
.121
OCq    Quartzite (Lower Ordovician or older)
.122
Or     Ramshorn Slate (Ordovician?)
.123
OCb    Bayhorse Dolomite (Lower Ordovician and 
        Upper Cambrian)
.124
Cg     Garden Creek Phyllite (Cambrian?)
.125
Ccqs   Quartzite, shale, and carbonate rocks of the 
        Squaw Creek area (Cambrian)
 
    PALEOZOIC (?) AND PROTEROZOIC (?) ROCKS
.126
OCZl   Interbedded quartzite, dolomite. and argillite of
        Leaton Gulch and Pennal Gulch areas (Ordovician?,
        Cambrian?, Late Proterozoic?)
.127
rp     Roof pendants and xenoliths of metamorphic rock
        in Idaho batholith, undivided (Paleozoic? or 
        Proterozoic?)
.128
rps    Schist roof pendant
.129
rpq    Quartzite roof pendant
.130
rpc    Calc-silicate rock roof pendant
 
    MIDDLE PROTEROZOIC SEDIMENTARY 
      AND METAMORPHIC ROCKS
.131
Yl     Lawson Creek Formation 
.132
Ys     Swauger Formation
.133
Yg     Gunsight Formation
.134
Ya     Apple Creek Formation
.135
Yb     Big Creek Formation
.136
Yy     Yellowjacket Formation
.137
Yh     Hoodoo Quartzite
 
    INTRUSIVE ROCKS OF UNCERTAIN AGE
 
.138
dr     Diorite, quartz diorite and syenite
.139
sr     Quartz syenite, syenite and granite