﻿ROCKS 
  OF 
  THE 
  LEICESTEKSHIRE 
  COAL-FIELD. 
  21 
  

  

  in 
  contact 
  with 
  the 
  Main 
  Coal, 
  whilst 
  at 
  Boothorpe 
  we 
  know 
  they 
  

   overlie 
  strata 
  belonging 
  to 
  a 
  very 
  much 
  higher 
  horizon 
  in 
  the 
  Coal- 
  

   measures. 
  

  

  (2) 
  LlTHOLOGICAL 
  CHARACTERS 
  OF 
  THE 
  BEDS. 
  

  

  Throughout 
  the 
  whole 
  of 
  the 
  district 
  we 
  are 
  describing, 
  the 
  Per- 
  

   mian 
  beds 
  maintain 
  certain 
  well-marked 
  lithological 
  characters, 
  

   which, 
  apart 
  from 
  any 
  consideration 
  as 
  to 
  the 
  stratigraphical 
  position 
  

   of 
  the 
  series, 
  are 
  sufficient 
  to 
  differentiate 
  them 
  with 
  certainty 
  from 
  

   both 
  the 
  Trias 
  and 
  the 
  Carboniferous. 
  At 
  their 
  outcrop 
  they 
  gener- 
  

   ally 
  yield 
  a 
  subsoil 
  of 
  deep 
  red 
  or 
  purple 
  clay, 
  sometimes 
  sandy, 
  and 
  

   containing 
  more 
  or 
  less 
  of 
  brecciated 
  fragments 
  *. 
  When 
  observed 
  

   in 
  freshly 
  cut 
  sections, 
  such 
  as 
  those 
  described 
  above 
  (pp. 
  6 
  & 
  8) 
  as 
  

   occurring 
  at 
  Swadlincote 
  and 
  the 
  Boothorpe 
  Clay 
  Works, 
  it 
  is 
  seen 
  

   that 
  the 
  red 
  and 
  purple 
  clays, 
  which 
  are 
  associated, 
  as 
  a 
  rule, 
  with 
  

   thin 
  white 
  sandy 
  bands 
  and 
  several 
  beds 
  of 
  breccia, 
  occur 
  at 
  the 
  base 
  

   of 
  the 
  series. 
  The 
  red 
  clays 
  are 
  much 
  more 
  purple 
  in 
  colour 
  and 
  more 
  

   homogeneous 
  in 
  character 
  than 
  the 
  marls 
  of 
  the 
  Lower 
  Keuper, 
  and 
  

   are 
  of 
  a 
  decidedly 
  different 
  shade 
  of 
  colour 
  from 
  the 
  marls 
  of 
  the 
  

   Upper 
  Keuper. 
  The 
  Permian 
  marls 
  with 
  their 
  breccias 
  are, 
  at 
  

   Swadlincote, 
  followed 
  upwards 
  by 
  a 
  few 
  feet 
  of 
  evenly 
  bedded, 
  fine- 
  

   grained 
  sandstones, 
  which 
  are 
  fissile 
  and 
  often 
  beautifully 
  ripple- 
  

   marked. 
  These 
  sandstones 
  are 
  of 
  a 
  light 
  buff 
  colour, 
  as 
  a 
  rule, 
  very 
  

   soft, 
  and 
  contain 
  numerous 
  specks 
  of 
  a 
  blackish 
  mineral. 
  They 
  are 
  

   very 
  unlike 
  the 
  saudstones 
  found 
  on 
  any 
  other 
  geological 
  horizon 
  in 
  

   the 
  district. 
  

  

  The 
  principal 
  interest, 
  however, 
  centres 
  in 
  the 
  brecciated 
  bands, 
  

   which, 
  it 
  will 
  be 
  seen, 
  have 
  yielded 
  a 
  large 
  amount 
  of 
  information 
  

   throwing 
  light 
  upon 
  the 
  physical 
  changes 
  attending 
  the 
  deposition 
  

   of 
  the 
  whole 
  series. 
  

  

  The 
  brecciated 
  bands 
  are 
  rarely 
  more 
  than 
  3 
  feet 
  in 
  thickness, 
  and 
  

   contain 
  fragments 
  of 
  a 
  great 
  variety 
  of 
  rock, 
  all 
  comparatively 
  little 
  

   water-worn, 
  and 
  varying 
  in 
  size 
  from 
  that 
  of 
  a 
  pea 
  to 
  5 
  or 
  6 
  inches 
  

   across. 
  Occasionally 
  still 
  larger 
  fragments 
  occur; 
  bat 
  as 
  a 
  rule 
  

   they 
  do 
  not 
  measure 
  more 
  than 
  1| 
  to 
  2 
  inches 
  along 
  their 
  greatest 
  

   dimensions. 
  

  

  These 
  angular 
  pieces 
  of 
  rock 
  are 
  imbedded 
  in 
  a 
  bluish-grey 
  matrix 
  

   of 
  calcareous 
  sand, 
  which 
  varies 
  very 
  much 
  in 
  hardness. 
  Sometimes, 
  

   as 
  at 
  Measham 
  and 
  Oakthorpe, 
  it 
  forms, 
  with 
  the 
  enclosed 
  fragments, 
  

   a 
  rock 
  of 
  a 
  considerable 
  degree 
  of 
  hardness, 
  whilst 
  at 
  other 
  places, 
  

   as 
  jNewhall 
  Park 
  Colliery, 
  Swadlincote, 
  &c, 
  it 
  is 
  only 
  in 
  part 
  con- 
  

   solidated, 
  and 
  readily 
  breaks 
  down 
  under 
  the 
  action 
  of 
  the 
  weather. 
  

  

  * 
  The 
  red 
  marly 
  soil 
  at 
  the 
  outcrop 
  of 
  the 
  Permians 
  is 
  of 
  a 
  very 
  rich 
  and 
  

   fertile 
  character, 
  and 
  affords 
  in 
  this 
  respect 
  a 
  great 
  contrast 
  to 
  the 
  very 
  light, 
  

   sandy, 
  and 
  pebbly 
  soil 
  of 
  the 
  Bunter, 
  and 
  to 
  the 
  cold, 
  heavy 
  soil 
  of 
  the 
  under- 
  

   lying 
  Coal-measure 
  clays. 
  The 
  Permian 
  marls 
  are 
  in 
  some 
  localities 
  used 
  

   for 
  " 
  dressing 
  " 
  the 
  sandy 
  soils 
  of 
  the 
  Bunter, 
  which 
  are 
  so 
  light 
  as 
  occasionally 
  

   to 
  be 
  completely 
  denuded 
  by 
  the 
  action 
  of 
  the 
  wind. 
  

  

  