﻿THE 
  

  

  AMERICAN 
  JOURNAL 
  OF 
  SCIENCE 
  

  

  [FO 
  URTH 
  SERIES.] 
  

  

  Art. 
  XL. 
  — 
  The 
  Upper 
  Devonian 
  Delta 
  of 
  the 
  Appalachian 
  

   G 
  ' 
  eosyncline 
  / 
  by 
  Joseph 
  Bakrell. 
  

  

  Part 
  I. 
  The 
  delta 
  and 
  its 
  relations 
  to 
  the 
  interior 
  sea.* 
  

  

  Contents. 
  

  

  Page 
  

  

  Introduction 
  and 
  summary 
  429 
  

  

  Previous 
  views 
  regarding 
  conditions 
  of 
  origin 
  _ 
  433 
  

  

  Criteria 
  for 
  separation 
  of 
  subaerial 
  and 
  subaqueous 
  delta 
  

  

  deposits 
  _._. 
  436 
  

  

  Distribution 
  and 
  character 
  of 
  the 
  significant 
  formations.. 
  440 
  

  

  Purpose 
  of 
  the 
  descriptions 
  440 
  

  

  The 
  Oneonta 
  formation 
  ._ 
  441 
  

  

  The 
  Portage 
  beds 
  441 
  

  

  The 
  Catskill 
  formation 
  442 
  

  

  The 
  Chemung 
  formation 
  446 
  

  

  The 
  Skunnemunk 
  conglomerate 
  447 
  

  

  The 
  Rensselaer 
  grit 
  448 
  

  

  The 
  Pocono 
  sandstone 
  _ 
  449 
  

  

  Sections 
  of 
  the 
  Catskill-Pocono 
  formations 
  on 
  the 
  Schuyl- 
  

   kill 
  River, 
  Pennsylvania 
  450 
  

  

  The 
  Catskill 
  on 
  the 
  Potomac 
  River 
  459 
  

  

  Reconstruction 
  of 
  physiography 
  and 
  climate 
  of 
  the 
  Cats- 
  

   kill 
  delta 
  463 
  

  

  Comparison 
  of 
  the 
  Catskill 
  and 
  Skunnemunk 
  with 
  the 
  

  

  Si 
  walik 
  formation. 
  . 
  . 
  463 
  

  

  Conditions 
  of 
  origin 
  of 
  the 
  several 
  Appalachian 
  forma- 
  

   tions.... 
  464 
  

  

  Inferences 
  regarding 
  climate 
  _ 
  468 
  

  

  Introduction 
  and 
  Summary. 
  

  

  The 
  Upper 
  Devonian 
  sediments 
  of 
  the 
  Appalachian 
  geosyn- 
  

   cline 
  in 
  southeastern 
  New 
  York 
  and 
  northeastern 
  Pennsylvania 
  

   consist, 
  except 
  at 
  the 
  base, 
  of 
  a 
  great 
  thickness 
  of 
  red 
  shales 
  

   and 
  gray 
  sandstones 
  known 
  as 
  the 
  Oneonta 
  and 
  Catskill 
  forma- 
  

  

  * 
  Part 
  II 
  on 
  Factors 
  Controlling 
  the 
  present 
  Limits 
  of 
  the 
  Strata 
  

   and 
  Part 
  III 
  on 
  The 
  Relations 
  of 
  the 
  Delta 
  to 
  Appalachia 
  will 
  be 
  pub- 
  

   lished 
  in 
  subsequent 
  numbers. 
  

  

  Am. 
  Jour. 
  Sci. 
  — 
  Fourth 
  Series, 
  Vol. 
  XXXVI, 
  No. 
  215. 
  — 
  November, 
  1913. 
  

   29 
  

  

  