﻿DETAILS 
  OF 
  THE 
  DEVELOPED 
  TERRITORY. 
  99 
  

  

  The 
  first 
  oil 
  zone 
  (A), 
  which 
  lies 
  from 
  250 
  to 
  500 
  feet 
  above 
  zone 
  B, 
  

   is 
  struck 
  at 
  depths 
  ranging 
  from 
  1,400 
  to 
  2,450 
  feet. 
  Its 
  thickness 
  

   ranges 
  from 
  a 
  few 
  feet 
  to 
  about 
  50 
  feet; 
  according 
  to 
  the 
  logs 
  it 
  is 
  

   lacking 
  in 
  some 
  of 
  the 
  wells, 
  the 
  first 
  oil 
  being 
  encountered 
  in 
  zone 
  B. 
  

   The 
  oil-bearing 
  strata 
  in 
  zone 
  A 
  are 
  largely 
  shale, 
  which 
  afford 
  a 
  

   reservoir 
  for 
  the 
  oil, 
  probably 
  on 
  account 
  of 
  their 
  fractured 
  condition. 
  

   Beds 
  of 
  fine 
  sand 
  in 
  this 
  zone 
  ma} 
  r 
  also 
  contain 
  some 
  of 
  the 
  petroleum. 
  

  

  The 
  second 
  oil 
  zone 
  (B), 
  occurs 
  at 
  depths 
  of 
  1,950 
  to 
  3,150 
  feet 
  

   and 
  is 
  penetrated 
  by 
  all 
  of 
  the 
  wells 
  in 
  this 
  area. 
  It 
  ranges 
  in 
  thick- 
  

   ness 
  from 
  nearly 
  50 
  to 
  about 
  250 
  feet, 
  in 
  the 
  wells; 
  one 
  of 
  the 
  wells, 
  

   however, 
  is 
  said 
  to 
  encounter 
  petroliferous 
  beds 
  intermittently 
  from 
  

   the 
  top 
  of 
  zone 
  B 
  for 
  a 
  distance 
  of 
  550 
  feet 
  downward. 
  The 
  oil- 
  

   bearing 
  strata 
  consist 
  of 
  alternating 
  layers 
  of 
  hard 
  shale 
  and 
  fine 
  

   sandstone. 
  

  

  The 
  third 
  oil 
  zone 
  (C), 
  occurs 
  from 
  500 
  to 
  600 
  feet 
  lower 
  in 
  the 
  

   wells 
  than 
  zone 
  B 
  and 
  consists 
  of 
  two 
  parts, 
  each 
  from 
  25 
  to 
  50 
  feet 
  

   thick, 
  separated 
  by 
  a 
  layer 
  of 
  shale 
  of 
  variable 
  thickness; 
  in 
  one 
  of 
  

   the 
  wells, 
  however, 
  the 
  intervening 
  shale 
  is 
  missing 
  and 
  the 
  strata 
  

   are 
  richly 
  impregnated 
  with 
  oil 
  from 
  the 
  top 
  of 
  the 
  zone 
  for 
  a 
  distance 
  

   I 
  of 
  250 
  feet 
  downward, 
  to 
  a 
  point 
  where 
  a 
  3-foot 
  layer 
  of 
  water 
  sand 
  

   1 
  limits 
  the 
  productive 
  zone. 
  In 
  practically 
  all 
  the 
  wells 
  in 
  the 
  field 
  

   zone 
  C 
  is 
  very 
  rich, 
  and 
  nearly 
  all 
  the 
  wells 
  tapping 
  it 
  are 
  fine 
  pro- 
  

   ducers. 
  

  

  PRODUCT. 
  

  

  The 
  oil 
  obtained 
  in 
  the 
  area 
  under 
  discussion 
  averages 
  somewhat 
  

   , 
  better 
  than 
  that 
  in 
  the 
  area 
  to 
  the 
  east, 
  and 
  has 
  a 
  gravity 
  of 
  26° 
  to 
  28° 
  

   Baume, 
  with 
  an 
  average 
  somewhere 
  between 
  26° 
  and 
  27°. 
  As 
  is 
  com- 
  

   mon 
  in 
  other 
  portions 
  of 
  the 
  field, 
  the 
  gas 
  pressure 
  in 
  most 
  of 
  the 
  

   wells 
  is 
  high. 
  

  

  The 
  production 
  of 
  the 
  individual 
  wells 
  ranges 
  from 
  100 
  to 
  2,700 
  

   barrels 
  per 
  day, 
  the 
  well 
  yielding 
  the 
  latter 
  amount 
  being 
  said 
  to 
  have 
  

   had 
  an 
  initial 
  daily 
  output 
  of 
  5,000 
  barrels 
  for 
  a 
  short 
  time. 
  In 
  one 
  

   series 
  of 
  wells 
  those 
  down 
  the 
  dip 
  are 
  more 
  productive 
  than 
  those 
  

   nearer 
  the 
  axis 
  of 
  the 
  anticline, 
  the 
  variation 
  being 
  at 
  least 
  partially 
  

   accounted 
  for 
  by 
  a 
  thickening 
  of 
  the 
  oil 
  zone 
  away 
  from 
  the 
  axis. 
  

  

  HARTNELL-BROOKSHIRE 
  AREA. 
  

   LOCATION 
  AND 
  STRUCTURE. 
  

  

  The 
  area 
  comprising 
  the 
  southern 
  portion 
  of 
  the 
  Hartnell 
  tract 
  

   and 
  Brookshire 
  property 
  and 
  the 
  southeastern 
  portion 
  of 
  the 
  Radium 
  

   lease 
  is 
  located 
  on 
  or 
  adjacent 
  to 
  the 
  ridge 
  running 
  northwestward 
  

   from 
  a 
  point 
  near 
  the 
  west 
  end 
  of 
  Graciosa 
  Ridge, 
  and 
  in 
  the 
  broad 
  

   valley 
  to 
  the 
  south. 
  The 
  major 
  structural 
  feature 
  developed 
  in 
  the 
  

  

  