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GEOLOGY]

UNITED STATES

631

Ordovician.
  Saluda bed 20 ± ft. 
  Richmond formation   300 ± ”
  Lorraine formation 300 ± ”
  Eden (Utica) shale 250 ”
  Trenton limestone 130 ”


Iowa

  Glacial drift.
 Unconformity.
Upper Cretaceous.
  Benton formation  0- 150 ft.
  Dakota formation 50- 100 ”
 Unconformity.
Pennsylvanian.
  Missouri formation1500 ft.
  Des Moines formation250- 400 ”
 Unconformity.
Mississippian.
  St Louis limestone100 ft.
  Osage (Augusta) formation200- 300 ”
  Kinderhook formation150- 200 ”
Devonian.
  Lime Creek formation80 ft.
  State Quarry beds 20-  40 ”
  Sweetland Creek shales 20-  40 ”
 Unconformity.
  Cedar Valley limestone250- 300 ft.
  Wapsipinicon formation (Independence, Fayette, Davenport)100- 150 ”
Silurian.
  Anamosa limestone 50-  75 ft.
  Le Claire limestone50 ”
  Delaware stage200 ”
 Unconformity.
Ordovician.
  Maquoketa shales175 ft.
 Possible Unconformity.
  Galena-Trenton limestone290 ft.
  St Peters sandstone100 ”
  Oneota formation (includes Shakopee, New Richmond and Oneota proper)300 ”
Cambrian.
  St Croix sandstone ( = Potsdam)1000 ft.
 Unconformity.
Proterozoic.
  Sioux quartzite(?) 

This section is fairly representative for much of the central Mississippi Basin.


Oklahoma

Pennsylvanian.
   (Summit removed by erosion.)
  Seminole conglomerate50 ft.
  Holdenville shale260 ”
  Wewaka formation700 ”
  Wetumka shale120 ”
  Calvin sandstone 145- 240 ”
  Senora formation 140- 485 ”
  Stuart shale  90- 280 ”
  Thurman sandstone  80- 260 ”
  Boggy shale2000-2600 ”
  Savannah sandstone 750-1100 ”
  McAlester shale1150-1500 ”
  Hartshorne sandstone 150- 200 ”
  Atoka formation (Chickahoc chert lentil)3200 ”
  Wapanucka limestone 100- 150 ”
Mississippian.
  Caney shale1500 ft.
Devonian.
  Woodford chert600 ft.
Silurian.
  Hunton limestone160 ft
  Sylvan shale (upper part)  50- 100 ”
Ordovician.
  Sylvan shale (lower part)250 ft.
  Viola limestone750 ”
  Simpson series1600 ”
  Arbuckle limestone4000-6000 ”
Cambrian.
  Regan sandstone  50- 100 ft.
 Unconformity.
Pre-Cambrian.
  Tishomingo granite(?) 

Composite section. The upper part is taken from vicinity of Coalgate, the lower part from the vicinity of Atoka.


West Central Colorado

Eocene or later.
  West Elk breccia3000 ft.
 Unconformity.
Cretaceous.
  Ruby formation2500 ft.
 Unconformity.
  Ohio formation (local only)200 ft.
 Unconformity.
  Laramie formation2000 ft.
  Montana formation2800 ”
  Niobrara formation100- 200 ”
  Benton formation150- 300 ”
  Dakota formation 40- 300 ”
Jurassic.
  Gunnison formation350- 500 ft.
 Unconformity.
Pennsylvanian.
  Maroon conglomerate4500 ft.
 Possible unconformity.
  Weber limestone100- 550 ft.
 Unconformity.
Mississippian.
  Leadville limestone400- 525 ft.
 Apparent unconformity.
Ordovician.
  Yule limestone350- 450 ft.
Upper Cambrian.
  Sawatch quartzite 50- 350 ft.
 Unconformity.
Archean.


The Bighorn Mountains of Wyoming

Cretaceous.
  De Smet formation (shale and sandstone)4000 ft.
  Kingsbury conglomerate   0-1500 ”
  Piney formation (shale and sandstone)2500 ”
  Parkman sandstone350 ”
  Pierre shale1500-3500 ”
  Colorado formation1050-1700 ”
Comanchean.
  Cloverly formation (upper part may be Cretaceous)  30- 300 ft.
  Morrison formation (may be Jurassic) 100- 300 ”
Jurassic.
  Sundance formation 250- 350 ft.
 Unconformity.
Triassic and Permian.
  Chugwater formation 750-1200 ft.
Pennsylvanian.
  Tensleep sandstone  30- 150 ft.
  Amsden sandstone 150- 350 ”
Mississippian.
  Madison limestone1000 ft.
 Unconformity.
Ordovician.
  Bighorn limestone300 ft.
 Unconformity.
Cambrian (Upper).
  Deadwood formation900 ft.
 Unconformity.
Pre-Cambrian.
  Granites.

This section is fairly representative for the Rocky Mountains.


Southern California

Quaternary.
  Alluvium, &c.
  Terrace deposits and dune sand.
Pliocene (?)
  Paso Robles formation1000 + ft.
 Unconformity.
Miocene (?)
  Pismo formation (in south part of area)
  Santa Margarita (in north part of area)
 Unconformity.
Miocene.
  Monterey shale5000-7000 ft.
  Vaquero sandstone   0- 500 ”
 Unconformity.
Cretaceous.
  Atascadero formation3000-4000 ft.
 Unconformity.
Comanchean.
  Toro formation (Knoxville)3000 ± ft.
 Unconformity.
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