THE   CORDILLERAS.  791 
contain  Olenellus  fauna.  YValcott  says  that  this  lower  series, 
although  in  a  most  excellent  condition  for  affording  fossils,  did  not 
reveal  any.  The  pre- Olenellus  rocks  are  rather  gently  folded,  al- 
though the  dips  are  sometimes  steep.  The  metamorphism  of  the 
rocks  is  largely  by  consolidation  and  cementation,  although  the 
quartzites  everywhere  show  the  effects  of  orogenic  movements  and 
in  places  approach  quartz  schists.  The  series  is  here  correlated  with 
the  "  Uinta  "  quartzite  and  the  Belt  series,  and  is  therefore  assigned 
to  the  Algonkian. 
To  the  south,  in  the  Little  Cottonwood  district,  is  a  great  mass  of 
white,  laminated  granite.  King  and  Emmons  believed  the  evidence, 
on  the  whole,  to  favor  the  pre-Algonkian  origin  of  this  granite. 
Geikie,  from  a  few  general  observations,  later  believed  it  to  be  intru- 
sive. Van  Hise  inclined  toward  Geikie's  view.  The  observations  of 
Boutwell  in  1900  finally  proved  the  intrusive  character  of  this  granite. 
These  views  were  accepted  by  Emmons  in  1908. 
Promontory  Ridge,  Fremont  Island,  and  Antelope  Island. — In  the 
range  composed  of  Promontory  Ridge  and  Fremont  and  Antelope 
islands  the  Archean  rocks  occur  in  typical  development.  Resting  on 
these,  according  to  Hague,  is  a  conformable  series  of  quartzites  and 
mica  schists  containing  a  zone  of  calcareous  sandstones  and  several 
beds  of  limestone,  the  whole  estimated  to  be  3,800  feet  in  thickness. 
No  fossils  are  found  in  these  rocks,  and  they  are  presumably  the 
equivalent  of  the  quartzites  of  the  Wasatch  Mountains,  and  therefore 
probably  Algonkian. 
SECTIOK  5.    NEVADA. 
SUMMARY    OF  LITERATURE. 
Schtel/'5  in  1855,  states  that  in  the  Humboldt  and  other  island 
mountains  of  the  desert  west  of  Salt  Lake  are  granites,  syenite-. 
quartzose  rocks,  and  clay  slates. 
Gilbert,16  in  1875,  states  that  the  ridges  of  the  Basin  Range  system 
are  in  part  composed  of  granitic  and  cognate  rocks.  The  granite 
occupies  various  positions.  Often  it  is  the  nucleus  of  the  range 
against  which  inclined  strata  rest.  Elsewhere  it  appears  in  dikes. 
traversing  either  the  sedimentary  rocks  or  other  granites.  In  a  few 
instances  it  was  observed  to  overlie  the  sedimentary  rocks,  while  in  a 
number  of  localities  the  evidence  of  its  eruptive  character  is  une- 
quivocal; in  others  it  is  plainly  metamorphic,  and  in  by  far  the 
majority  of  cases  it  appears  to  have  assumed  its  relation  to  the  un- 
doubted sedimentary  rocks  before  the  upheaval  of  the  combination. 
In  the  Granite  mining  district  the  section  shows  a  white  crystalline 
marble  overlain  by  granite,  which  appears  to  extend  from  the  summit 
of  the  range  to  the  opposite  base.    The  axis  ol*  the  Snake  River  Range 
