﻿STRUCTURE 
  AND 
  CONDITIONS 
  AFFECTINC 
  PRESENCE 
  OF 
  OIL. 
  77 
  

  

  rather 
  uniformly 
  along 
  the 
  northeastern 
  border 
  of 
  the 
  area, 
  and 
  de- 
  

   velop 
  toward 
  the 
  southeast 
  into 
  the 
  syncline 
  crossing 
  Tunnel 
  Canyon 
  

   and 
  Horse 
  Gulch 
  just 
  north 
  of 
  Sisquoc 
  River. 
  The 
  high, 
  broad 
  ridge 
  

   between 
  Bone 
  Mountain 
  and 
  Manzanita 
  Mountain 
  is 
  composed 
  of 
  

   Monterey 
  shale, 
  which 
  lies 
  approximately 
  flat, 
  and 
  toward 
  the 
  north- 
  

   west 
  becomes 
  one 
  arm 
  of 
  the 
  great 
  syncline 
  which 
  extends 
  through 
  

   Goodchild's 
  ranch 
  on 
  Labrea 
  Creek 
  and 
  is 
  traceable 
  almost 
  to 
  Colson 
  

   Fork 
  of 
  Tepusquet 
  Creek. 
  A 
  similar 
  syncline, 
  possibly 
  the 
  same, 
  

   extends 
  from 
  Colson 
  Fork 
  northwestward 
  across 
  Tepusquet 
  Creek 
  to 
  

   the 
  margin 
  of 
  the 
  Lompoc 
  quadrangle. 
  The 
  northeastern 
  arm 
  of 
  this 
  

   fold 
  forms 
  the 
  high 
  ridge 
  extending 
  along 
  the 
  southwestern 
  side 
  of 
  

   Buckhorn 
  Canyon. 
  

  

  It 
  is 
  possible 
  that 
  the 
  pre-Monterey 
  rocks 
  north 
  of 
  Bee 
  Rock 
  Can- 
  

   yon 
  plunge 
  down 
  monoclinally 
  under 
  the 
  Vaqueros 
  in 
  a 
  fold 
  at 
  right 
  

   angles 
  to 
  the 
  wide 
  anticlinal 
  fold 
  that 
  exposes 
  the 
  former. 
  Such 
  a 
  

   plunge 
  would 
  be 
  apt 
  to 
  give 
  rise 
  to 
  the 
  northeast-southwest 
  table 
  

   between 
  Bone 
  Mountain 
  and 
  Manzanita 
  Mountain 
  that 
  interrupts 
  the 
  

   structure 
  to 
  the 
  northwest 
  and 
  southeast, 
  and 
  this 
  table 
  may, 
  there- 
  

   fore, 
  represent 
  a 
  buckling 
  across 
  an 
  otherwise 
  continuous 
  structure. 
  

  

  Southwest 
  of 
  Los 
  Coches 
  Mountain 
  one 
  or 
  more 
  folds 
  are 
  over- 
  

   turned, 
  but 
  the 
  northwestern 
  extensions 
  of 
  these 
  folds 
  have 
  not 
  been 
  

   examined. 
  

  

  The 
  region 
  southeast 
  of 
  Round 
  Corral 
  and 
  Asphaltum 
  creeks 
  is 
  

   occupied 
  by 
  several 
  sharp 
  folds 
  which 
  strike 
  in 
  a 
  general 
  northwest- 
  

   southeast 
  direction. 
  Overturning 
  is 
  not 
  uncommon 
  in 
  this 
  series 
  of 
  

   folds, 
  one 
  notable 
  example 
  being 
  an 
  anticline 
  on 
  the 
  southern 
  flank 
  

   of 
  Zaca 
  Peak. 
  West 
  of 
  Round 
  Corral 
  Creek 
  the 
  structure 
  lines 
  bow 
  

   around 
  from 
  a 
  northwesterly 
  to 
  a 
  westerly 
  or 
  west-southwesterly 
  

   direction, 
  the 
  folds 
  at 
  the 
  same 
  time 
  becoming 
  less 
  compressed 
  and 
  

   the 
  conditions 
  for 
  the 
  retention 
  of 
  the 
  oil 
  in 
  the 
  basal 
  sands 
  of 
  the 
  

   hard 
  shale 
  series 
  correspondingly 
  better. 
  

  

  'faults. 
  

  

  There 
  is 
  strong 
  evidence 
  of 
  a 
  fault 
  zone 
  passing 
  north 
  of 
  the 
  nar- 
  

   row 
  area 
  of 
  intrusive 
  rock 
  north 
  of 
  Zaca 
  Lake, 
  and 
  thence 
  north- 
  

   westward 
  as 
  far 
  as 
  the 
  head 
  of 
  Rattlesnake 
  Canyon. 
  The 
  resultant 
  

   downthrow 
  along 
  this 
  zone 
  of 
  displacement 
  is 
  on 
  the 
  southwest, 
  

   probably 
  amounting 
  to 
  a 
  good 
  many 
  hundred 
  feet 
  toward 
  the 
  east 
  

   edge 
  of 
  the 
  Lompoc 
  quadrangle. 
  Toward 
  the 
  northwest 
  this 
  fault 
  

   apparently 
  dies 
  out 
  or 
  merges 
  into 
  a 
  syncline. 
  

  

  Just 
  east 
  of 
  Los 
  Coches 
  Mountain 
  there 
  may 
  be 
  another 
  fault 
  

   which 
  brings 
  up 
  the 
  uppermost 
  Yaqueros 
  on 
  the 
  north. 
  A 
  third 
  

   fault 
  between 
  the 
  Pliocene 
  and 
  Monterey 
  may 
  extend 
  from 
  a 
  point 
  

   near 
  the 
  mouth 
  of 
  Round 
  Corral 
  Canyon 
  to 
  Labrea 
  Creek, 
  

   1784— 
  Bull. 
  322—07 
  6 
  

  

  