﻿446 
  Geological 
  Society. 
  

  

  PROCEEDINGS 
  OF 
  LEARNED 
  SOCIETIES. 
  

  

  GEOLOGICAL 
  SOCIETY. 
  

  

  December 
  3rcl, 
  1913. 
  — 
  Dr. 
  Aubre}^ 
  Straban, 
  F.R.S., 
  President, 
  

   ill 
  tbe 
  Cbair. 
  

  

  The 
  following 
  commnnications 
  were 
  read 
  : 
  — 
  

  

  1. 
  * 
  A 
  Contribution 
  to 
  our 
  Knowledge 
  of 
  the 
  G-eology 
  of 
  the 
  

   Kent 
  Coalfield.' 
  By 
  Dr. 
  E. 
  A. 
  Newell 
  Arber, 
  M.A., 
  F.L.S., 
  F.G.S. 
  

  

  In 
  this 
  paper 
  an 
  attempt 
  is 
  made 
  to 
  give 
  a 
  general 
  and 
  connected 
  

   account 
  of 
  the 
  Carboniferous 
  rocks 
  of 
  Kent, 
  based 
  on 
  the 
  evidence 
  

   of 
  some 
  nineteen 
  borings 
  or 
  sinkings. 
  The 
  Mesozoic 
  cover 
  of 
  this 
  

   wholly 
  concealed 
  coalfield 
  is 
  ignored. 
  It 
  is 
  shown 
  that 
  the 
  proved 
  

   area 
  is 
  200 
  square 
  miles 
  (128,000 
  acres), 
  partly 
  lying 
  beneath 
  land, 
  

   and 
  partly 
  beneath 
  the 
  North 
  Sea, 
  the 
  Straits 
  of 
  Dover, 
  and 
  the 
  

   English 
  Channel. 
  The 
  general 
  strike 
  is 
  about 
  30"^ 
  south 
  of 
  east 
  

   and 
  north 
  of 
  Avest, 
  and 
  the 
  dip 
  of 
  the 
  Transition 
  Coal 
  Measures 
  is 
  

   2° 
  to 
  3^, 
  in 
  the 
  two 
  localities 
  where 
  reliable 
  evidence 
  is 
  alone 
  

   available 
  on 
  this 
  point. 
  

  

  The 
  area, 
  as 
  a 
  whole, 
  is 
  a 
  syncline, 
  limited 
  on 
  the 
  north 
  and 
  

   south 
  by 
  Armorican 
  folds, 
  of 
  which 
  the 
  northern 
  has 
  been 
  now 
  

   fairly 
  accurately 
  located. 
  There 
  is 
  evidence 
  also 
  of 
  a 
  fold 
  on 
  the 
  

   east 
  ; 
  and 
  it 
  is 
  maintained 
  that 
  the 
  Kent 
  coalfield 
  is 
  not 
  continuous 
  

   with 
  that 
  of 
  the 
  Pas 
  de 
  Calais. 
  There 
  are 
  reasons 
  for 
  believing 
  

   that 
  the 
  Avestern 
  boundary 
  is 
  a 
  great 
  fault. 
  

  

  The 
  chief 
  sm-face-featm-e 
  of 
  the 
  Coal 
  Measures 
  is 
  that 
  of 
  an 
  

   inclined 
  plane, 
  sloping 
  rapidly 
  but 
  regularly 
  westwards 
  and 
  south- 
  

   westwards 
  from 
  an 
  elevated 
  region 
  near 
  Ripple 
  and 
  Deal 
  in 
  the 
  

   east. 
  

  

  The 
  Lower 
  Carboniferous 
  rocks 
  exceed 
  450 
  feet 
  in 
  thickness, 
  and 
  

   were 
  denuded 
  before 
  the 
  Coal 
  Measures 
  were 
  deposited. 
  

  

  The 
  Coal 
  Measures 
  consist 
  of 
  the 
  Transition 
  Series 
  (1700 
  to 
  

   2000 
  feet 
  thick), 
  and 
  the 
  Middle 
  Coal 
  Measures 
  (2000 
  feet). 
  No 
  

   Lower 
  Coal 
  Measures 
  or 
  Millstone 
  Grit 
  occur. 
  The 
  measures 
  are 
  

   grey 
  throughout, 
  and 
  no 
  red 
  rocks, 
  Espley 
  rocks, 
  Sjjiro)'his- 
  

   limestones, 
  nor 
  igneous 
  rocks 
  occur. 
  

  

  The 
  coals 
  are 
  well 
  distributed, 
  and 
  are 
  often 
  of 
  considerable 
  

   thickness, 
  although 
  there 
  is 
  a 
  frequent 
  tendency 
  to 
  splitting 
  and 
  

   inconstancy. 
  Steam 
  and 
  household 
  coals 
  predominate, 
  but 
  gas- 
  

   coals 
  also 
  occur. 
  

  

  The 
  most 
  productive 
  portions 
  of 
  the 
  measures 
  are 
  the 
  higher 
  

   part 
  of 
  the 
  Transition 
  and 
  the 
  lower 
  j^art 
  of 
  the 
  Middle 
  Coal 
  

   Measures. 
  

  

  2. 
  ' 
  On 
  the 
  Fossil 
  Floras 
  of 
  tbe 
  Kent 
  Coalfield.' 
  By 
  Dr. 
  E. 
  A. 
  

   Newell 
  Arber, 
  M.A., 
  F.L.S., 
  F.G.S. 
  

  

  The 
  floras 
  of 
  ten 
  further 
  borings 
  in 
  Kent 
  are 
  here 
  recorded, 
  and 
  

   the 
  number 
  of 
  species 
  known 
  from 
  the 
  Kent 
  Coalfield 
  is 
  raised 
  to 
  

   9G, 
  as 
  compared 
  with 
  10 
  known 
  in 
  1892 
  and 
  26 
  in 
  1909. 
  A 
  

  

  