﻿Related 
  Sedimentary 
  Surface 
  Forms. 
  249 
  

  

  largely 
  determine 
  the 
  position 
  of 
  the 
  largest 
  water 
  waves 
  

   and 
  the 
  ripples 
  resulting 
  from 
  them. 
  

  

  4. 
  We 
  are 
  now 
  in 
  a 
  position 
  to 
  discuss 
  the 
  interesting 
  

   case 
  of 
  the 
  ripples 
  in 
  the 
  Bedford 
  and 
  Berea 
  formations 
  

   at 
  the 
  base 
  of 
  the 
  Mississippian 
  section 
  of 
  eastern 
  and 
  

   central 
  Ohio, 
  which 
  were 
  so 
  well 
  described 
  by 
  Hyde. 
  20 
  

  

  The 
  facts 
  entering 
  into 
  this 
  discussion 
  may 
  be 
  sum- 
  

   marized 
  as 
  follows 
  : 
  

  

  (1) 
  Where 
  the 
  ripples 
  are 
  most 
  typically 
  developed, 
  

   both 
  formations 
  consist 
  of 
  fine-grained 
  sandstones 
  inter- 
  

   stratified 
  with 
  more 
  or 
  less 
  shaly 
  portions. 
  

  

  (2) 
  The 
  beds 
  are 
  from 
  less 
  than 
  one 
  inch 
  to 
  at 
  most 
  

   two 
  or 
  three 
  feet 
  thick. 
  

  

  (3) 
  The 
  individual 
  layers 
  are 
  not 
  persistent, 
  pinching 
  

   out 
  and 
  reappearing 
  at 
  different 
  levels, 
  much 
  like 
  the 
  

   limestones 
  of 
  the 
  limestone-shale 
  series 
  of 
  the 
  Cincinna- 
  

   tian 
  at 
  the 
  type 
  locality. 
  

  

  (4) 
  Where 
  typically 
  developed, 
  almost 
  every 
  layer 
  is 
  

   rippled. 
  

  

  (5) 
  Only 
  oscillation-ripples 
  are 
  present. 
  

  

  ( 
  6 
  ) 
  Most 
  of 
  these 
  ripples 
  trend 
  very 
  nearly 
  N 
  53° 
  W, 
  

   with 
  subordinate 
  variations 
  in 
  both 
  directions 
  covering 
  

   an 
  extreme 
  total 
  range 
  of 
  69°. 
  

  

  (7) 
  Occasionally, 
  smaller 
  ripples 
  intersecting 
  the 
  

   larger 
  ones 
  at 
  right 
  angles 
  or 
  nearly 
  so, 
  are 
  found. 
  21 
  

   Only 
  one 
  case 
  of 
  typical 
  interference 
  pattern, 
  produced 
  

   by 
  the 
  intersection 
  of 
  equally 
  large 
  ripples, 
  has 
  come 
  to 
  

   my 
  knowledge. 
  

  

  (8) 
  These 
  ripples 
  were 
  observed 
  over 
  an 
  area 
  115 
  

   miles 
  long 
  and 
  20 
  miles 
  wide. 
  

  

  From 
  observation 
  (5) 
  we 
  have 
  already 
  concluded 
  the 
  

   absence 
  of 
  tidal 
  or 
  wind-drift 
  currents 
  from 
  the 
  lower 
  

   part 
  of 
  the 
  water. 
  The 
  former 
  indicates 
  the 
  absence 
  of 
  

   free 
  communication 
  with 
  the 
  open 
  sea, 
  the 
  latter 
  a 
  depth 
  

   sufficiently 
  large 
  in 
  proportion 
  to 
  the 
  area 
  to 
  prevent 
  the 
  

   action 
  of 
  drift 
  on 
  the 
  bottom. 
  That 
  the 
  limestone-shale 
  

   series 
  of 
  the 
  Ordovician 
  of 
  the 
  Cincinnati 
  region 
  owes 
  its 
  

   peculiar 
  character 
  to 
  the 
  stirring 
  action 
  of 
  storms 
  on 
  the 
  

   sea-bottom 
  and 
  subsequent 
  redistribution 
  of 
  the 
  material 
  

   thrown 
  into 
  suspension 
  through 
  the 
  action 
  of 
  surface 
  

   drifts, 
  appears 
  highly 
  probable 
  from 
  an 
  analysis 
  of 
  these 
  

  

  20 
  Jesse 
  E. 
  Hyde, 
  Jour. 
  Geol., 
  vol. 
  19, 
  pp. 
  257-269, 
  1911. 
  

  

  21 
  Several 
  good 
  specimens 
  are 
  in 
  the 
  collection 
  of 
  Ohio 
  State 
  University. 
  

  

  