﻿GEOLOGY. 
  29 
  

  

  has 
  been 
  considered 
  upper 
  Cretaceous 
  and 
  of 
  one 
  in 
  southeastern 
  

   Santa 
  Barbara 
  County 
  that 
  has 
  been 
  ascribed 
  to 
  the 
  Eocene. 
  Its 
  

   age 
  is 
  therefore 
  much 
  in 
  doubt. 
  It 
  may 
  also 
  include 
  at 
  the 
  top 
  part 
  

   of 
  the 
  Vaqueros 
  (lower 
  Miocene), 
  which 
  overlies 
  this 
  doubtful 
  ter- 
  

   rane 
  and 
  of 
  which 
  the 
  base 
  has 
  not 
  been 
  definitely 
  determined. 
  

  

  Structurally 
  the 
  strata 
  included 
  in 
  this 
  pre-Monterey 
  group 
  lie 
  

   beneath 
  the 
  Monterey 
  and 
  upper 
  Vaqueros, 
  but 
  though 
  far 
  older 
  

   they 
  do 
  not 
  bear 
  so 
  strongly 
  the 
  marks 
  of 
  intense 
  folding 
  as 
  do 
  the 
  

   brittle 
  Monterey 
  shales. 
  They 
  are, 
  however, 
  steeply 
  upturned, 
  and 
  

   the 
  lines 
  of 
  folding, 
  as 
  in 
  the 
  case 
  of 
  the 
  other 
  formations, 
  are 
  in 
  gen- 
  

   eral 
  in 
  a 
  northwest-southeast 
  direction. 
  

  

  tejon, 
  sespe, 
  and 
  vaqueros 
  formations, 
  undifferentiated 
  

  

  (eocene-miocene) 
  . 
  

  

  general 
  statement. 
  

  

  The 
  Santa 
  Ynez 
  Range 
  is 
  mostly 
  composed 
  of 
  a 
  thick 
  terrane 
  of 
  

   marine 
  sediments 
  equivalent 
  to 
  a 
  part 
  or 
  all 
  of 
  the 
  Tejon 
  formation 
  

   and 
  the 
  Vaqueros 
  formation. 
  The 
  former 
  is 
  Eocene 
  and 
  the 
  latter 
  

   lower 
  Miocene 
  in 
  age. 
  This 
  terrane 
  comprises 
  a 
  continuous 
  succes- 
  

   sion 
  of 
  marine 
  sediments 
  of 
  detrital 
  origin, 
  seeming 
  to 
  present 
  no 
  

   point 
  at 
  which 
  an 
  angular 
  unconformity 
  exists, 
  although 
  the 
  line 
  at 
  

   the 
  base 
  of 
  the 
  coarse 
  conglomerate 
  containing 
  the 
  Vaqueros 
  fossils 
  

   doubtless 
  marks 
  a 
  long 
  time 
  interval. 
  

  

  In 
  the 
  preliminary 
  report 
  on 
  the 
  Santa 
  Maria 
  district 
  a 
  mention 
  is 
  

   made 
  of 
  the 
  Sespe 
  formation 
  as 
  being 
  represented 
  here, 
  and 
  a 
  small 
  

   area 
  of 
  it 
  is 
  shown 
  on 
  the 
  map 
  accompanying 
  that 
  report. 
  The 
  

   Sespe 
  formation 
  belongs 
  to 
  the 
  Eocene 
  or 
  Oligocene 
  and 
  is 
  a 
  distinct 
  

   formation 
  above 
  the 
  Tejon 
  and 
  below 
  the 
  Vaqueros. 
  It 
  occurs 
  ex- 
  

   tensively 
  in 
  the 
  Santa 
  Ynez 
  Mountains 
  north 
  of 
  Santa 
  Barbara, 
  and 
  

   an 
  outcrop 
  of 
  blood-red 
  sandstone 
  in 
  this 
  range 
  3h 
  miles 
  south 
  of 
  

   the 
  Santa 
  Ynez 
  Mission 
  was 
  indicated 
  on 
  the 
  outline 
  map 
  as 
  belong- 
  

   ing 
  to 
  the 
  Sespe 
  because 
  of 
  its 
  lithologic 
  resemblance 
  to 
  the 
  typical 
  

   rocks 
  of 
  this 
  formation. 
  This 
  small 
  area 
  has, 
  however, 
  not 
  been 
  

   separately 
  shown 
  on 
  the 
  present 
  map, 
  as 
  there 
  is 
  no 
  good 
  proof 
  of 
  

   its 
  age. 
  It 
  is 
  quite 
  possible 
  that 
  the 
  Sespe 
  formation 
  is 
  represented 
  

   in 
  parts 
  of 
  this 
  western 
  portion 
  of 
  the 
  range 
  by 
  rocks 
  not 
  recogniz- 
  

   able 
  on 
  the 
  lithologic 
  grounds 
  which 
  are 
  deemed 
  sufficient 
  for 
  the 
  

   determination 
  of 
  this 
  formation 
  in 
  the 
  vicinity 
  of 
  Santa 
  Barbara 
  or 
  

   the 
  Ojai 
  Valley, 
  to 
  the 
  east; 
  or 
  it 
  may 
  be 
  that 
  sedimentation 
  was 
  

   not 
  operative 
  in 
  the 
  western 
  part 
  of 
  the 
  range 
  during 
  Sespe 
  time, 
  and 
  

   therefore 
  that 
  rocks 
  of 
  that 
  age 
  are 
  lacking 
  from 
  the 
  geologic 
  section 
  

   in 
  this 
  region. 
  The 
  amount 
  of 
  work 
  done 
  in 
  the 
  Santa 
  Ynez 
  Range 
  

   does 
  not 
  warrant 
  a 
  full 
  discussion 
  of 
  the 
  structure 
  and 
  relations 
  of 
  

  

  a 
  Bull. 
  U. 
  S. 
  Geol. 
  Survey 
  No. 
  317, 
  1907, 
  pp. 
  1-69, 
  

   1784-^Bull. 
  322—07 
  3 
  

  

  