THE   CORDILLERAS.  795 
and  the  series  resembles  the  Cambrian  of  T>onneville  Peak,  Aqui 
Mountains.  In  the  Seetoya  and  Shoshone  ranges  the  quartzites  re- 
ferred to  the  Weber  are  between  heavy  beds  of  limestones,  and  in 
Two  Cubits  it  conformably  overlies  an  enormous  development  of 
Wasatch  limestone. 
The  stratified  rocks  overlying  the  Havallah,  Pahute,  West  Hum- 
boldt, and  Truckee  granites  are  referred  to  the  Triassic;  those  over- 
lying the  granites  of  the  Pahsupp  Range  are  referred  to  the  Jurassic ; 
while  the  gray  slates  resting  unconformably  above  the  Sahwave  arc 
referred  to  the  Miocene.  These  references  are  mostly  made  on  litho- 
logical  grounds,  because  no  Paleozoic  strata  have  been  recognized  wesl 
of  the  Battle  Mountains,  although  in  certain  cases  paleontological 
evidence  is  found. 
It  is  remarked  that  throughout  Nevada  are  large  bodies  of  quartz- 
ites without  any  clue  to  their  stratigraphical  relations  with  an  under- 
lying or  overlying  limestone,  the  adjacent  rocks  being  either  granites 
or  Tertiary  volcanic  outflows.  It  is  then  exceedingly  difficult,  if  not 
impossible,  definitely  to  determine  their  true  geological  horizons.  In 
many  cases  lithological  and  structural  resemblances  furnish  a  strong 
aid,  and,  when  followed  up,  not  infrequently  throw  the  evidence 
in  favor  of  one  or  the  other  of  the  great  zones  of  quartzites;  but  in 
many  cases  such  resemblances  are  meager,  and  the  references  are 
made  on  theoretical  grounds,  being  on  slight  evidence,  or  even  per- 
sonal impressions  received  in  the  field. 
King,36  in  1878,  describes  many  of  the  Nevada  ranges. 
In  the  Gosiute  Range  the  Archean  rocks  are  granite,  granite  por- 
phyries, and  crystalline  dolomites,  all  of  which  are  interlaminated 
and  are  chemically  allied  to  those  of  the  Humboldt  Range.  That  the 
granite  porphyries  are  interstratified  with  the  marbles  confirms  the 
probability  of  their  being  metamorphic. 
The  Archean  of  the  Humboldt  Range,  with  the  exception  of  a  small 
body  of  granite,  is  composed  of  a  conformable  series  of  gneisses, 
gneissoid  schists  which  are  sometimes  hornblendic,  dolomitic  lime- 
stones, and  quartzites,  all  of  which  dip  to  the  west.  1<  i-  evident  by 
the  entire  absence  of  easterly  dipping  Archean  and  Paleozoic  rock- 
that  a  fault  similar  to  that  at  the  Wasatch  has  cut  down  the  core  of 
the  range  from  north  to  south,  and  that  the  eastern  half  i-  depressed 
below  the  level  of  the  Quaternary  plain.  The  White  (loud  Peat 
granite  bears  a  singular  resemblance  to  some  of  the  Huronian  grani- 
toid rocks,  also  conceived  to  be  metamorphic.  The  granite  appear- 
to  underlie  conformably  the  series  of  schists.  The  gneisses  of  Clover 
Peak  can  not  be  distinguished  in  hand  specimen  Prom  a  granite,  ex- 
cept that  there  is  an  indistinct  parallelism  of  ii-  dark  constituents. 
Between  this  stage  and  the  truly  schistose  gneisses  there  is  every 
possible  transition.     The  limestone  series  is  not  more  than  50  or  60 
