METASEDIMENTARY AND METAVOLCANIC ROCKS
  Sierra Madre--Granite gneiss, felsic gneiss, amphibolite, and metavolcanic rocks.  Xsv
  Medicine Bow Mountains--Granite gneiss, felsic gneiss, amphibolite, and hornblende gneiss.  Xsv
  Laramie Mountains--Pelitic schist, marble, granite gneiss, layered amphibolite, and felsic gneiss.
     Xsv
  Black Hills--Pelitic schist; includes minor amounts of granite and amphibolite.  Xsv
METASEDIMENTARY ROCKS--In Medicine Bow Mountains and Sierra Madre
  Libby Creek Group 3--Pelitic schist, amphibole schist, quartzite, diamictite, quartz-pebble con-
     glomerate, and marble.  Xlc
  Deep Lake Group 3--Quartzite, diamictite, pelitic schist, and quartz-pebble conglomerate.  Xdl
GRANITIC ROCKS OF 1,700-Ma AGE GROUP.  Xgv
QUARTZ DIORITE
  Sierra Madre--Encampment River Granodiorite 4; age 1,800 Ma.  Xqd
  Medicine Bow Mountains--Keystone Quartz Diorite 5.  Xqd
  Hartville uplift--Diorite of Twin Hills 6.  Xqd
MAFIC INTRUSIVE ROCKS
  Sierra Madre--Gabbro of Elkhorn Mountain; age 1,800 Ma.  Xm
  Medicine Bow Mountains--Mullen Creek 5 and Lake Owens 7 Mafic Complexes; older than
     1,700 Ma.  Xm
GRANITIC ROCKS OF 2,000-Ma AGE GROUP
  Medicine Bow Mountains--Gaps Intrusion 3 (granitic).  Xgo
  Hartville uplift--Granite and quartz monzonite of Flattop Butte 6; age 2,150+/- Ma.  Xgo