LIkaxsom^ND]         CRIPPLE    CREEK    DISTRICT,    COLORADO.  87 
The  elevations  range  from  9,000  to  nearly  11,000  feet  above  sea,  the 
highest  point  in  the  district  being  Trachyte  Mountain  (10,83G  feet). 
Bull  Hill  and  Bull  Cliff  are  but  slightly  lower.  The  drainage  is 
chiefly  southward  toward  the  Arkansas  River.  The  district  contains 
two  important  towns.  Cripple  Creek  is  situated  on  the  northwest 
side  of  the  producing  area,  while  Victor,  3  miles  distant,  lies  on  the 
southwest  edge  of  the  same  area.  Two  railroads  connect  the  district 
with  Colorado  Springs,  the  Colorado  Midland  circling  around  the 
north  side  of  Pikes  Peak,  while  the  Short  Line  descends  to  the  valley 
along  the  picturesque  eastern  slope  of  the  same  mountain.  The 
Florence  and  Cripple  Creep  Railroad  runs  southward  to  Florence,  in 
the  Arkansas  Valley.  An  excellent  system  of  electric-car  lines  con- 
nects the  towns  with  all  the  important  mines. 
GENERAL  GEOLOGY. 
FIRST    GEOLOGICAL    SURVEY    OF    THE    DISTRICT. 
When  Mr.  Whitman  Cross  made  his  careful  study  of  the  geology 
of  the  Cripple  Creek  district,  ten  years  ago,  mining  had  barely  begun 
and  the  various  hills  were  not,  as  now,  perforated  by  deep  under- 
ground workings.  That  his  work  has  in  general  stood  the  test  of 
subsequent  underground  exploration  and  continues  to  be  highly 
regarded  in  the  district  is  convincing  proof  of  its  high  quality.  Later 
workers,  however  they  may  modify  or  amplify  its  results,  should 
acknowledge  their  debt  to  the  pioneer  who  first  deciphered  the  history 
of  this  volcanic  district.  The  account  of  general  geology,  as  given 
(by  Cross,  may  be  very  briefly  summarized  as  follows : 
The  Cripple  Creek  hills  lie  near  the  eastern  border  of  an  elevated 
nd  much  dissected  plateau,  which  slopes  gently  westward  for  40 
miles,  from  the  southern  end  of  the  Colorado  Range,  dominated  by 
Pikes  Peak,  to  the  relatively  low  hills  connecting  the  Mosquito  and 
^angre  de  Cristo  ranges.     The  prevailing  rocks  of  this  plateau  are 
granites,  gneisses,  and  schists.     The  granites  inclose  masses  of  Algon- 
jrian  quartzite  and  are  therefore  post-Archean,  but   they  are  older 
pan  the  only  Cambrian  sediments  known  in  Colorado,  and  on  the 
pripple    Creek    map    have    been    indicated    as    Algonkian.     During 
[Tertiary  time  volcanic  eruptions  broke1  through  these  ancient  rocks  at 
veral  points  and  piled  tuffs,  breccias,  and  lavas  upon  the  uneven 
urface  of  the  plateau.     The  eruptive  rocks  of  the  Cripple   Creek 
istrict  are  the  products  of  one  of  the  smaller  isolated  volcanic  centers 
f  this  period,  a  center  characterized  by  the  eruption  of  phonolite, 
'Inch  does  not  occur  elsewhere  in  this  general  region. 
The  most  voluminous  products  of  the  Cripple  Creek  volcano  now 
reserved   are  tuffs  and    breccias.     They  occupy   a    rudely  elliptical 
