THE   CORDILLERAS.  781 
10,000  or  12,000  feet  of  unconformable  beds,  part  of  which  consists 
very  largely  of  quartzite  and  is  regarded  as  pre-Carboniferous,  while 
the  upper  part  is  placed  in  the  Upper  Coal  Measures  and  Permo- 
Carboniferous.  The  Upper  Coal  Measures  are  limestones  and  sand- 
stones and  bear  fossils;  but  in  the  great  thickness  of  lower  beds  re- 
ferred to  the  Weber  no  fossils  are  found. 
King,36  in  1878,  describes  the  Archean  rocks  of  the  Uinta  Range  as 
a  group  of  pure  white  quartzites,  hornblende  schists,  and  hydromica 
(paragonite)  schist,  richly  charged  with  garnet,  staurolite,  and 
minute  crystals  of  cyanite.    They  are  referred  to  the  Huronian. 
The  Paleozoic  rocks  of  the  Uintas  rest  unconformably  upon  the 
Archean.  They  comprise  an  immense  body  of  quartzites  and  indu- 
rated sandstones  intercalated  with  shales,  12,000  feet  in  thickness, 
referred — not,  however,  without  some  questioning — to  the  Weber 
quartzite  or  Middle  Coal  Measures.  Directly  overlying  these  is  a 
series  of  sandstones  and  limestones  having  a  thickness  of  2,000  or 
2,500  feet,  in  which  Coal  Measure  fossils  were  obtained. 
Peale,37  in  1879,  describes  in  the  Green  River  district,  at  station 
77,  a  Cambrian  section  consisting  largely  of  quartzite  and  amounting 
to  7,000  feet.  At  station  130  is  another  red  quartzite  which  has  a 
limestone  below  it,  and  below  them  a  series  of  green  chloritic  rocks 
unlike  those  of  any  other  section  in  the  district.  The  author  is  in- 
clined to  place  these  below  the  Cambrian  quartzites,  and  considers 
them  of  probably  Huronian  age.  None  of  these  sections  expose  the 
underlying  crystalline  schists. 
Van  Hise,38  in  1889,  examined  the  Archean  core  of  the  Uintas. 
The  so-called  white  quartzite  is  found  to  be  largely  composed  of  white 
feldspar.  It  is  thoroughly  crystalline,  and  its  lithological  affinities 
are  with  the  granites  rather  than  with  the  quartzites.  The  black 
bands  contained  in  it,  supposed  by  some  to  represent  original  layers  of 
a  different  constitution,  and  by  others  to  represent  dikes,  were  found 
to  be  much  altered  eruptives.  The  unconformable  contact  between 
the  Uinta  series  and  the  Archean  was  seen  at  many  points. 
Boutwell,39  in  1902,  in  the  course  of  a  reconnaissance  in  the 
western  Uintas,  found  in  limestones  on  the  divide  between  the  head- 
ward  portions  of  Provo  and  Du  Chesne  several  lots  of  fossils  indica- 
tive of  their  Lower  Carboniferous  (Mississippian)  age.  These  lime- 
stones appear  on  broad  structural  grounds  to  overlie  the  great  quartz- 
ite of  the  central  Uintas.  He  concludes  that  this  sandstone-quartz- 
ite  series  is  proved  by  fossil  evidence  to  be  earlier  than  Lower  Car- 
boniferous, and  thus  that  the  interior  area  of  the  Uintas  is  not  later 
than  Silurian. 
Berkev,10  in  1905,  discusses  the  stratigraphy  of  the  Uinta  Moun- 
tains ami  suo-gests  a  correlation  of  the  basal  Uinta  quartzite  with  tin1 
basal  "  Cambrian  "  quartzite  of. the  Wasatch.     The  thickness  in  the 
