290  PRE-CAMBRIAN    ROCKS    OF    NORTH    AMERICA.  [bull.  86. 
Hayden,21  in  1873,  describes  syenite  in  the  Little  Cottonwood  canyon 
of  the  Wasatch  at  the  base  of  the  series,  upon  which  rest  feklspathic 
gneissic  strata,  and  unconforniably  upon  these  the  lower  qtfartzites. 
The  Wasatch  is  probably  a  complete  anticlinal  fold. 
Peale,22  in  1873,  states  that  the  base  of  the  mountains  near  Ogden 
is  for  the  most  part  a  red  syenite  which  passes  into  granite  and  gneiss, 
and  contains  in  places  veins  of  hornblende,  quartz,  and  specular  iron. 
The  granites  of  Cottonwood  creek  are  conspicuously  bedded,  the  dip 
being  about  50°  or  70°  to  the  east,  and  they  contain  rounded  pebble-like 
masses  of  a  dark  color  inclosed  within  the  gray  matrix.  These  gran- 
ites are  cut  by  veins  of  feldspar.  The  pebble-like  masses  suggest  that 
the  formation  is  metamorphic. 
Bradley,18  in  1873,  regards  the  core  of  the  Wasatch  as  metamorphic. 
The  occurrence  ol  angular  and  rounded  patches  of  dark  material  in  the 
granite  of  the  Little  Cottonwood  canyon  is  taken  as  evidence  that 
these  were  pebbles  of  a  conglomerate  before  its  metamorphism.  The 
rocks  are  chiefly  hornblendic  gneiss  and  syenite,  with  quartz  veins. 
Howell  31,  in  1875,  states  that  in  Bock  canyon,  near  Provo,  pebbly 
chlorite-schist  is  unconforniably  below  hard  quartzite. 
Emmons,  (S.  F.)6,  in  1877,  describes  the  Wasatch  range  as  a  sharp 
north  and  south  anticlinal  fold  over  preexisting  ridges  of  granite  andj 
unconformable  Archean  beds,  the  axis  being  bent  and  contorted  by 
longitudinal  compression  so  that  at  times  it  assumes  a  direction  approx- 
imately east  and  west.  In  connection  with  the  folding  is  a  widely  ^ 
spread  system  of  faulting  and  dislocation,  in  a  direction  generally  par- ; 
allel  to  the  main  line  of  elevation,  which  has  cut  off  and  thrown  down 
the  western  members  of  the  longitudinal  folds  and  the  western  ends  of 
the  transverse  folds,  and  they  are  now  buried  beneath  the  valley  plains. 
In  the  northern  region  is  a  second  broad  anticlinal  fold  to  the  east  of 
the  main  line  of  elevation.  This  mountain  range  occupies  the  line  of 
former  Archean  uplift,  around  which  were  deposited  a  thickness  of 
30,000  or  40,000  feet  of  practically  conformable  beds  extending  upward 
from  the  Cambrian  to  the  Jurassic.  At  the  base  of  the  Paleozoic  is  the 
Cambrian  formation,  which  has  a  small  thickness  of  calcareous  slates 
bearing  Primordial  fossils  and  a  great  thickness  of  white  quartzite,  in- 
cluding a  few  micaceous  beds  and  argillites,  the  whole  being  12,000- 
feet.  The  granite  mass  constituting  the  center  of  the  Wasatch  was 
not  protruded  through  the  sedimentary' rocks,  but  the  latter  were  de- 
posited around  them,  and  their  present  conditions  are  due  to  subsequent; 
elevation,  flexure,  dislocation,  and  erosion. 
In  the  Cottonwood  canyons  is  a  large  mass  of  granite  which  shows 
a  conoidal  structure,  and,  while  massive,  has  distinct  planes  of  cleavage 
which  dip  50°  to  the  westward.     It  is  a  white,  rather  coarse  grained 
granite,  dotted  here  and  there  with  round  black  spots  where  there  has; 
been  a  concentration  of  the  dark  green  hornblende,  which  is  a  promjH 
nent  constituent  of  the  mass.     On  the  western  flanks  of  the  Cotton- : 
