﻿S. 
  Powers 
  — 
  The 
  Butler 
  Salt 
  Borne. 
  

  

  137 
  

  

  1600 
  feet 
  in 
  Anderson 
  County. 
  Overlying 
  the 
  gumbo 
  

   the 
  logs 
  show 
  predominately 
  sand 
  which 
  attains 
  a 
  thick- 
  

   ness 
  of 
  about 
  1200 
  feet 
  below 
  the 
  base 
  of 
  the 
  Mount 
  

   Selman 
  formation. 
  An 
  additional 
  700 
  feet 
  of 
  sand 
  which 
  

   is 
  in 
  part 
  if 
  not 
  wholly 
  of 
  Mount 
  Selman 
  age 
  is 
  found 
  in 
  

   the 
  lower 
  portion 
  of 
  the 
  synclinorium 
  near 
  the 
  Nueces 
  

   River 
  in 
  Anderson 
  County. 
  

   A 
  comparison 
  of 
  estimates 
  of 
  thickness 
  is 
  tabulated 
  : 
  

  

  Anderson 
  Co. 
  

   Hopkins, 
  1917 
  

  

  Anderson 
  Co. 
  

   Well 
  logs 
  

  

  Freestone 
  Co. 
  

   Butler 
  dome 
  

  

  Formation 
  

  

  

  Thickness, 
  feet 
  

  

  

  

  r 
  Mount 
  Selman 
  

  

  

  

  

  

  

  formation. 
  . 
  

  

  350-600 
  

  

  

  700+ 
  

  

  200+ 
  

  

  Eocene 
  ■< 
  

  

  Wilcox 
  form- 
  

   ation 
  

  

  450-650 
  

  

  ' 
  sand 
  1200 
  ) 
  

   shale 
  800 
  ± 
  f 
  

  

  1000 
  

  

  

  Midway 
  form- 
  

  

  

  

  s 
  

  

  

  

  ation 
  

  

  250 
  

  

  

  

  400- 
  

  

  

  Navarro 
  form- 
  

  

  

  *■ 
  

  

  800 
  ± 
  

  

  400+ 
  

  

  

  ation 
  

  

  600-900 
  

  

  

  

  

  

  Tavlor 
  marl 
  . 
  . 
  

  

  800-1000 
  

  

  

  

  

  Upper 
  

   Cretaceous 
  • 
  

  

  Austin 
  chalk 
  . 
  

  

  400-500 
  

  

  

  250 
  

  

  

  Eagle 
  Ford 
  

  

  . 
  1 
  

  

  

  

  

  

  shale 
  

  

  " 
  Woodbine" 
  

  

  350-400 
  

  

  - 
  900- 
  

  

  -1150 
  

  

  

  

  oil 
  sand. 
  . 
  . 
  . 
  

  

  j 
  

  

  

  

  

  The 
  conspicuous 
  discrepancies 
  between 
  the 
  figures 
  of 
  

   Hopkins 
  and 
  the 
  well 
  log 
  data 
  are 
  the 
  relatively 
  great 
  

   thickness 
  assigned 
  to 
  the 
  Wilcox 
  formation 
  and 
  the 
  rela- 
  

   tively 
  small 
  thickness 
  assigned 
  to 
  the 
  underlying 
  shales 
  

   in 
  the 
  well 
  logs. 
  Some 
  error 
  in 
  correlation 
  or 
  in 
  

   measurement 
  is 
  suggested. 
  A 
  thinning 
  of 
  the 
  Cretaceous 
  

   south 
  of 
  the 
  present 
  outcrop 
  is 
  possible, 
  but 
  a 
  compari- 
  

   son 
  of 
  all 
  the 
  logs 
  of 
  deep 
  wells 
  thus 
  far 
  drilled 
  points 
  to 
  

   strikingly 
  uniform 
  subsurface 
  conditions. 
  

  

  The 
  estimated 
  thickness 
  of 
  the 
  "Wilcox 
  on 
  the 
  sides 
  of 
  

   the 
  dome 
  is 
  half 
  that 
  in 
  the 
  Anderson 
  County 
  well 
  logs. 
  

   This 
  is 
  accounted 
  for 
  by 
  an 
  unconformity, 
  the 
  presence 
  

   of 
  which 
  is 
  indicated 
  by 
  an 
  almost 
  horizontal 
  ferruginous 
  

   sandstone 
  capping 
  an 
  abrupt 
  hill 
  on 
  the 
  south 
  Butler 
  

   road 
  about 
  1000 
  feet 
  west 
  of 
  the 
  edge 
  of 
  the 
  saline 
  

   prairie. 
  Only 
  750 
  feet 
  east 
  of 
  this 
  hill 
  the 
  Wilcox 
  sands 
  

   dip 
  23 
  degrees 
  west, 
  while 
  1000 
  feet 
  west 
  of 
  it 
  irregularly 
  

  

  