﻿44 
  BOSE 
  : 
  GEOLOGY 
  OF 
  THE 
  LOWEK 
  NARBADA 
  VALLEY. 
  

  

  latter, 
  indicate 
  considerable 
  changes 
  of 
  physical 
  conditions, 
  and 
  con- 
  

   sequently 
  a 
  proportionate 
  lapse 
  of 
  t'ime. 
  

  

  The 
  remarkable 
  change 
  in 
  the 
  mineral 
  character 
  also 
  proves 
  a 
  corre- 
  

   sponding 
  alteration 
  in 
  the 
  configuration 
  of 
  the 
  cretaceous 
  sea, 
  and, 
  there- 
  

   fore, 
  in 
  the 
  physical 
  geography 
  of 
  the 
  country 
  from 
  which 
  the 
  rivers 
  

   derived 
  their 
  sediment. 
  

  

  On 
  these 
  considerations, 
  and 
  on 
  the 
  strength 
  of 
  the 
  fact 
  that 
  two 
  of 
  

   the 
  most 
  characteristic 
  forms 
  occur 
  in 
  the 
  highest 
  (Arialur) 
  division 
  of 
  

   the 
  South 
  Indian 
  cretaceous 
  series, 
  I 
  am 
  inclined 
  to 
  correlate 
  the 
  coralline 
  

   limestone, 
  of 
  course 
  roughly, 
  with 
  the 
  latter. 
  x 
  

  

  Section 
  IV. 
  — 
  Lametas. 
  

  

  Area, 
  lithology, 
  Sfc. 
  — 
  A 
  small 
  patch 
  of 
  unfossiliferous 
  limestones, 
  

   quarried 
  for 
  building 
  purposes, 
  occurs 
  2 
  miles 
  south 
  of 
  Punghat, 
  in 
  the 
  

   western 
  portion 
  of 
  the 
  district 
  of 
  Hoshangabad 
  (map 
  No. 
  1) 
  . 
  They 
  are 
  

   probably 
  Lametas. 
  

  

  North 
  of 
  Punassa 
  (map 
  No. 
  1) 
  there 
  are 
  some 
  horizontally 
  bedded 
  

   gritstones 
  and 
  conglomerates 
  deposited 
  in 
  a 
  hollow 
  in 
  the 
  Vindhyans. 
  

   The 
  colour 
  of 
  the 
  matrix 
  resembles 
  that 
  of 
  the 
  latter, 
  which 
  is 
  no 
  doubt 
  

   owing 
  to 
  the 
  detritus 
  being 
  derived 
  from 
  them 
  ; 
  and 
  on 
  stratigraphical 
  

   grounds 
  I 
  have 
  no 
  doubt 
  that 
  the 
  rocks 
  in 
  question 
  are 
  not 
  Vindhyans. 
  

   But 
  they 
  may 
  belong 
  to 
  the 
  Gondwana 
  sandstone. 
  Their 
  remoteness, 
  

   however, 
  from 
  the 
  known 
  outcrops 
  of 
  this 
  series, 
  and 
  proximity 
  to 
  beds 
  

   with 
  fresh 
  water 
  shells 
  of 
  inter-trappean 
  affinities, 
  seemed 
  to 
  me 
  to 
  be 
  in 
  

   favour 
  of 
  their 
  being 
  nearer 
  in 
  age 
  to 
  the 
  latter. 
  

  

  At 
  Bhorla 
  (2§ 
  miles 
  north-east 
  of 
  Punassa), 
  the 
  conglomerates 
  just 
  

   mentioned 
  are 
  noticed 
  in 
  the 
  bed 
  of 
  a 
  tank, 
  covered 
  by 
  black 
  soil 
  over- 
  

  

  1 
  At 
  Kherwan, 
  and 
  in 
  the 
  vicinity 
  of 
  Deola 
  and 
  Chirakhan, 
  fields 
  of 
  coralline 
  

   limestone 
  are 
  strewn 
  over 
  with 
  pieces 
  of 
  what 
  appear 
  to 
  he 
  jaspidified 
  wood. 
  Between 
  

   Chirakhan 
  and 
  Deola, 
  just 
  hy 
  the 
  road-side, 
  there 
  is 
  lying 
  a 
  fossilised 
  tree, 
  hut 
  the 
  silicifica. 
  

   tion 
  has 
  gone 
  so 
  far 
  as 
  to 
  render 
  its 
  identification 
  extremely 
  difficult, 
  if, 
  indeed, 
  possible. 
  

   This 
  is 
  most 
  likely 
  the 
  fossil 
  trunk 
  noticed 
  by 
  Colonel 
  Keatinge 
  in 
  January 
  1857. 
  

   (Journ. 
  As. 
  Soc. 
  Ken., 
  Vol. 
  XXVII, 
  p. 
  121). 
  

  

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  41 
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