﻿212 
  H. 
  E. 
  Gregory 
  — 
  Geologic 
  Sketch 
  of 
  

  

  Feet 
  

  

  6. 
  Shale 
  ; 
  purplish 
  drab 
  ; 
  full 
  of 
  plant 
  fragments 
  ; 
  two 
  thin 
  

   beds 
  of 
  limestone 
  included 
  20 
  

  

  7. 
  Shale 
  and 
  thin-bedded 
  limestone 
  ; 
  transverse 
  seams 
  stained 
  

   with 
  limonite 
  __ 
  1*75 
  

  

  8. 
  Sandstone 
  ; 
  medium-grained 
  quartz, 
  clear, 
  subangular 
  

   to 
  rounded 
  ; 
  occasional 
  large 
  grains 
  ; 
  some 
  lime 
  ; 
  gray- 
  

   white 
  with 
  limonite 
  stains 
  ; 
  cross-bedded 
  ; 
  thin 
  to 
  heavy 
  ; 
  

  

  some 
  rare 
  spots 
  of 
  conglomerate 
  

  

  9,t 
  

  

  9. 
  Sandstone 
  ; 
  fine-grained, 
  rounded 
  quartz 
  ; 
  much 
  stained 
  

   by 
  limonite 
  ; 
  even-bedded 
  ; 
  mica 
  on 
  bedding 
  planes 
  50 
  

  

  10. 
  Shale 
  ; 
  drab 
  with 
  lenses 
  of 
  yellowish 
  limestone 
  4 
  

  

  11. 
  Limestone 
  ; 
  gray, 
  sandy 
  _._ 
  ^ 
  

  

  12. 
  Coal, 
  with 
  2" 
  band 
  of 
  sandstone. 
  Coal 
  of 
  fair 
  quality 
  

  

  and 
  with 
  little 
  " 
  bone 
  " 
  __ 
  2 
  

  

  13. 
  Shale 
  ; 
  gray 
  to 
  drab 
  with 
  purple 
  streaks 
  resembling 
  

   rootlets 
  8 
  

  

  14. 
  Sandstone 
  ; 
  fine-grained, 
  with 
  clear, 
  rounded, 
  quartz 
  peb- 
  

   bles, 
  white 
  flakes 
  and 
  limonite 
  ; 
  even, 
  heavy 
  beds 
  ; 
  

   toward 
  top 
  assumes 
  greenish 
  tone 
  and 
  contains 
  much 
  

   mica 
  and 
  lime 
  __ 
  20 
  

  

  1 
  5. 
  Shale 
  ; 
  gray 
  to 
  purple 
  30 
  

  

  16. 
  Sandstone 
  ; 
  fine, 
  with 
  well-rounded 
  quartz 
  grains, 
  and 
  

  

  white 
  specks 
  ; 
  some 
  muscovite 
  ; 
  thin, 
  even 
  bedding 
  6 
  

  

  17. 
  Shale 
  ; 
  gray, 
  with 
  thin 
  beds 
  of 
  limestone 
  40 
  

  

  18. 
  Sandstone 
  ; 
  fine, 
  with 
  clear, 
  well-rounded 
  quartz 
  grains 
  

  

  and 
  white 
  specks. 
  Mica 
  on 
  bedding 
  planes 
  ; 
  weathers 
  

   gray-white 
  ; 
  some 
  raised 
  veins 
  of 
  harder, 
  dark 
  rock 
  ; 
  bed- 
  

   ding 
  fairly 
  even 
  ; 
  some 
  cross-bedding 
  ; 
  some 
  twisted 
  

   beds 
  ; 
  calcareous 
  at 
  top 
  135 
  

  

  19. 
  Limestone 
  and 
  shale 
  ; 
  the 
  latter 
  predominate 
  ; 
  shale 
  is 
  

  

  drab 
  ; 
  limestone 
  is 
  gray, 
  to 
  a 
  limonite 
  yellow 
  ; 
  cross- 
  

   bedded 
  and 
  twisted 
  ; 
  has 
  much 
  mica 
  on 
  bedding 
  planes. 
  55 
  

  

  20. 
  Sandstone 
  ; 
  fine, 
  with 
  rounded, 
  clear 
  grains 
  of 
  quartz, 
  

   and 
  numerous 
  blotches 
  of 
  lime 
  or 
  other 
  white 
  mate- 
  

   rial 
  ; 
  general 
  weathered 
  color 
  gray-wliite 
  with 
  spots 
  and 
  

   bands 
  of 
  yellow 
  ; 
  medium 
  hard 
  ; 
  even-bedded 
  ; 
  massive 
  ; 
  

   occasional 
  small-, 
  rounded 
  concretions 
  of 
  limonite. 
  Strike 
  

  

  N 
  46° 
  W;dipK 
  E.Z40 
  . 
  30 
  

  

  Bibliography. 
  

  

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  Basadre, 
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