﻿96 
  SANTA 
  MABIA 
  OIL 
  DISTRICT, 
  CALIFORNIA. 
  

  

  The 
  production 
  of 
  the 
  wells 
  ranges 
  From 
  300 
  to 
  something 
  over 
  

   2,000 
  barrels 
  per 
  day. 
  Those 
  wells 
  which 
  penetrate 
  the 
  lowest 
  or 
  C 
  

   zone 
  are 
  the 
  hest 
  producers. 
  It 
  is 
  said 
  that 
  where 
  a 
  number 
  of 
  wells 
  

   are 
  located 
  comparatively 
  near 
  together 
  the 
  product 
  ion 
  of 
  each 
  well 
  is 
  

   largely 
  dependent 
  on 
  whether 
  or 
  not 
  the 
  adjacent 
  wells 
  are 
  producing, 
  

   a 
  fluctuation 
  of 
  50 
  percent 
  resulting 
  from 
  this 
  cause 
  in 
  some 
  instances. 
  

  

  PINAL-FOX 
  HOBBS 
  AREA. 
  

  

  LOCATION 
  WD 
  STKl 
  <TI 
  RE. 
  

  

  The 
  area 
  comprising 
  the 
  Fox 
  lease, 
  the 
  southwestern 
  part 
  of 
  the 
  

   Hobbs 
  lease, 
  and 
  the 
  northeastern 
  portion 
  of 
  the 
  Pinal 
  property, 
  

   occupies 
  the 
  ridge 
  and 
  two 
  adjacent 
  canyons 
  which 
  extend 
  north- 
  

   ward 
  from 
  the 
  central 
  portion 
  of 
  Graciosa 
  Ridge. 
  The 
  wells 
  are 
  

   located 
  in 
  an 
  area 
  of 
  considerable 
  structural 
  disturbance 
  caused 
  by 
  

   the 
  development 
  of 
  two 
  local 
  anticlines 
  on 
  the 
  northwestern 
  flank 
  of 
  

   the 
  main 
  Mount 
  Solomon 
  anticline. 
  These 
  two 
  minor 
  flexures 
  have 
  

   been 
  named 
  after 
  the 
  companies 
  under 
  whose 
  property 
  they 
  are 
  best 
  

   developed. 
  Although 
  the 
  position 
  assigned 
  to 
  them 
  on 
  the 
  map 
  is 
  

   more 
  or 
  less 
  hypothetical, 
  the 
  evidence 
  in 
  favor 
  of 
  it 
  is 
  fairly 
  complete, 
  

   and 
  their 
  location 
  explains 
  some 
  of 
  the 
  variations 
  in 
  production 
  of 
  

   adjacent 
  wells. 
  

  

  GEOLOGY 
  OF 
  THE 
  WELLS. 
  

  

  Practically 
  all 
  the 
  wells 
  within 
  this 
  area 
  start 
  in 
  the 
  Mont 
  ere}' 
  

   shale, 
  and 
  this 
  is 
  the 
  prevailing 
  formation 
  to 
  their 
  bottoms. 
  Certain 
  

   portions 
  of 
  the 
  shale 
  are 
  burnt 
  to 
  a 
  brick-red 
  color 
  by 
  the 
  combustion 
  

   of 
  their 
  hydrocarbon 
  contents, 
  the 
  burnt 
  shale 
  being 
  encountered 
  as 
  

   low 
  as 
  330 
  feet 
  in 
  one 
  of 
  the 
  wells. 
  The 
  burning 
  has 
  so 
  hardened 
  the 
  

   shale 
  in 
  places 
  as 
  to 
  render 
  drilling 
  in 
  them 
  more 
  difficult. 
  A 
  hard 
  

   limestone 
  " 
  shell 
  " 
  layer 
  was 
  encountered 
  in 
  one 
  of 
  the 
  wells 
  just 
  above 
  

   the 
  second 
  (B) 
  oil 
  zone. 
  Tar 
  or 
  asphaltum 
  occurs 
  in 
  some 
  of 
  the 
  wells 
  

   at 
  a 
  depth 
  of 
  about 
  600 
  feet, 
  in 
  others 
  at 
  various 
  depths 
  from 
  200 
  to 
  

   1,200 
  feet. 
  The 
  tar 
  is 
  in 
  many 
  wells 
  associated 
  with 
  black 
  shale. 
  

   Gas 
  accumulations 
  under 
  "shell" 
  and 
  other 
  impervious 
  layers 
  are 
  of 
  

   common 
  occurrence 
  both 
  in 
  the 
  oil 
  zones 
  and 
  locally 
  in 
  the 
  barren 
  

   overlying 
  shale. 
  Water 
  is 
  encountered 
  in 
  some 
  of 
  the 
  wells 
  at 
  

   depths 
  ranging 
  from 
  150 
  to 
  270 
  feet. 
  This 
  occurrence 
  is 
  noteworthy, 
  

   as 
  the 
  wells 
  in 
  the 
  group 
  to 
  the 
  east 
  are, 
  so 
  far 
  as 
  known, 
  quite 
  free 
  

   from 
  water 
  in 
  the 
  shale. 
  Its 
  occurrence 
  in 
  the 
  Fernando 
  sands 
  and 
  

   conglomerates 
  is 
  to 
  be 
  expected, 
  but 
  its 
  presence 
  in 
  sands 
  inter- 
  

   bedded 
  with 
  the 
  shale 
  is 
  unusual 
  for 
  this 
  field. 
  

  

  The 
  first 
  oil 
  zone 
  (A) 
  is 
  penetrated 
  in 
  the 
  wells 
  in 
  this 
  area 
  at 
  

   depths 
  ranging 
  from 
  a 
  little 
  more 
  than 
  1,600 
  to 
  2,650 
  feet, 
  or 
  between 
  

   400 
  and 
  600 
  feet 
  above 
  zone 
  B. 
  (See 
  PI. 
  X, 
  p. 
  92.) 
  Petroliferous 
  

   strata 
  occur 
  in 
  some 
  of 
  the 
  wells 
  above 
  this 
  horizon, 
  but 
  they 
  are 
  of 
  

  

  

  

  