﻿E. 
  WILSON 
  ON 
  THE 
  RHJSTICS 
  OP 
  NOTTINGHAMSHIRE. 
  451 
  

  

  43. 
  The 
  Rh^tics 
  of 
  Nottinghamshire. 
  By 
  E. 
  Wilson, 
  Esq., 
  E.G.S. 
  

   (Read 
  June 
  21, 
  1882.) 
  

  

  At 
  the 
  Meeting 
  of 
  the 
  British 
  Association 
  at 
  York 
  in 
  1881 
  I 
  gave 
  

   a 
  summarized 
  account 
  of 
  the 
  Rhaetic 
  rocks 
  of 
  Nottinghamshire. 
  In 
  

   the 
  present 
  communication 
  I 
  propose 
  to 
  give 
  a 
  more 
  detailed 
  descrip- 
  

   tion 
  of 
  the 
  same. 
  

  

  Rhaetic 
  rocks 
  were 
  first 
  noticed 
  in 
  this 
  district 
  about 
  fifteen 
  years 
  

   ago 
  near 
  Gainsborough, 
  in 
  Lincolnshire, 
  by 
  Mr. 
  E. 
  M. 
  Burton, 
  and 
  

   were 
  subsequently 
  observed 
  at 
  Newark 
  by 
  the 
  Rev. 
  A. 
  Irving 
  and 
  

   by 
  Mr. 
  Horace 
  Woodward, 
  and 
  at 
  Elton 
  Station, 
  on 
  the 
  Nottingham 
  

   and 
  Grantham 
  line, 
  by 
  Mr. 
  R. 
  Etheridge. 
  All 
  these 
  sections, 
  how- 
  

   ever, 
  were 
  more 
  or 
  less 
  incomplete, 
  either 
  above 
  or 
  below. 
  

  

  During 
  the 
  last 
  five 
  or 
  six 
  years 
  several 
  new 
  and 
  some 
  complete 
  

   sections 
  of 
  the 
  Rhaetic 
  beds 
  have 
  been 
  exposed 
  on 
  the 
  eastern 
  and 
  

   southern 
  borders 
  of 
  Notts, 
  chiefly 
  by 
  new 
  railway-works. 
  Unfortu- 
  

   nately 
  these 
  sections 
  are 
  now 
  all 
  covered 
  up 
  and 
  grass-grown. 
  See- 
  

   ing, 
  however, 
  that 
  they 
  disclosed 
  several 
  interesting 
  facts 
  and 
  some 
  

   new 
  features 
  concerning 
  this 
  series, 
  a 
  brief 
  record 
  of 
  them 
  appears 
  

   desirable. 
  

  

  The 
  Rhaetic 
  formation 
  in 
  this 
  country 
  is 
  usually 
  subdivided 
  into 
  

   three 
  groups 
  of 
  rocks, 
  viz. 
  : 
  — 
  (1) 
  Lower 
  fflicetie, 
  grey 
  or 
  green 
  in- 
  

   durated 
  marls, 
  the 
  " 
  Tea-green 
  marls 
  " 
  of 
  Etheridge 
  ; 
  (2) 
  Avicula- 
  

   contorta 
  series, 
  black 
  fissile 
  shales 
  with 
  subordinate 
  bands 
  of 
  sand- 
  

   stone 
  and 
  limestone, 
  with 
  or 
  without 
  one 
  or 
  more 
  " 
  bone-beds;" 
  and 
  

   (3) 
  Upper 
  fflicetie 
  or 
  White 
  Lias, 
  a 
  variable 
  series 
  of 
  shales 
  and 
  

   light-coloured 
  limestones. 
  This 
  tripartite 
  subdivision 
  has 
  generally 
  

   been 
  considered 
  to 
  hold 
  good 
  for 
  Nottinghamshire. 
  In 
  that 
  county 
  

   we 
  get 
  at 
  the 
  top 
  a 
  series 
  of 
  pretty 
  thickly 
  laminated 
  grey 
  marls 
  

   with 
  bands 
  or 
  layers 
  of 
  blue- 
  centred 
  septariiform 
  nodules 
  of 
  lime- 
  

   stone 
  containing 
  Estherke 
  ; 
  below 
  these 
  come 
  the 
  characteristic 
  thinly 
  

   laminated 
  black 
  shales 
  of 
  the 
  Avicula-contorta 
  series 
  ; 
  and 
  beneath 
  

   these 
  we 
  find 
  a 
  series 
  of 
  indurated 
  unfossiliferous 
  light-blue 
  marls 
  

   that 
  weather 
  a 
  yellowish-green 
  or 
  buff 
  colour, 
  and 
  break 
  up 
  into 
  

   cuboidal 
  fragments. 
  Eor 
  reasons 
  presently 
  to 
  be 
  given, 
  I 
  would 
  take 
  

   these 
  lowest 
  green 
  marls 
  from 
  the 
  Rhaetics 
  and 
  relegate 
  them 
  to 
  the 
  

   Keuper 
  formation 
  (see 
  figure, 
  p. 
  452). 
  

  

  I 
  now 
  proceed 
  to 
  describe 
  the 
  chief 
  Rhaetic 
  sections 
  which 
  are 
  or 
  

   have 
  at 
  different 
  times 
  been 
  exposed 
  in 
  this 
  district. 
  

  

  Gainsborough. 
  — 
  In 
  the 
  cuttings 
  of 
  the 
  Great 
  Northern 
  Railway 
  

   at 
  Lea, 
  near 
  Gainsboro', 
  the 
  Avicula-contorta 
  beds, 
  represented 
  by 
  at 
  

   least 
  25 
  feet 
  of 
  fossiliferous 
  black 
  fissile 
  shales 
  with 
  several 
  bands 
  

   of 
  micaceous 
  sandstone 
  and 
  one 
  or 
  two 
  bone-beds, 
  may 
  be 
  seen 
  rest- 
  

   ing 
  " 
  with 
  conformable 
  stratification 
  " 
  on 
  " 
  an 
  eroded 
  surface 
  " 
  of 
  

   blue 
  marl 
  of 
  the 
  Upper 
  Keuper 
  series. 
  The 
  upper 
  portion 
  of 
  the 
  

  

  