﻿THE 
  VINDHYANS. 
  19 
  

  

  Smaller 
  intrusions 
  are 
  very 
  abundant. 
  They 
  must 
  be 
  much 
  more 
  

   numerous 
  than 
  is 
  indicated 
  on 
  the 
  map. 
  It 
  is 
  only 
  where 
  the 
  super- 
  

   incumbent 
  beds 
  have 
  been 
  removed 
  by 
  denudation 
  that 
  the 
  dykes 
  are 
  

   exposed 
  to 
  observation 
  ; 
  and 
  of 
  those 
  that 
  are 
  observable 
  not 
  a 
  few 
  must 
  

   lie 
  hidden 
  in 
  inaccessible 
  jungles. 
  These 
  small 
  intrusions, 
  passing 
  

   through 
  what 
  may 
  be 
  called 
  incipient 
  fissures 
  of 
  eruption, 
  have, 
  unlike 
  

   the 
  larger 
  ones, 
  greatly 
  affected 
  the 
  contiguous 
  beds, 
  as 
  may 
  be 
  seen 
  all 
  

   along 
  the 
  Narbada, 
  from 
  Palasi 
  (Jamoti) 
  to 
  Mandhata. 
  The 
  dyke 
  rock 
  

   is 
  a 
  more 
  or 
  less 
  crystalline 
  dolerite, 
  which 
  shows 
  that 
  it 
  solidified 
  under 
  

   greater 
  pressure 
  than 
  that 
  which 
  produced 
  the 
  finer-grained 
  basalt 
  of 
  the 
  

   great 
  dyke 
  described 
  in 
  the 
  preceding 
  paragraph; 
  and 
  the 
  greater 
  

   resistance 
  offered 
  by 
  the 
  super-incumbent 
  rocks 
  in 
  the 
  former 
  case 
  

   probably 
  account 
  for 
  their 
  having 
  suffered 
  proportionately 
  greater 
  dis- 
  

   turbance. 
  This 
  disturbance, 
  however, 
  is, 
  as 
  I 
  shall 
  have 
  frequent 
  occa- 
  

   sion 
  to 
  remark 
  in 
  the 
  course 
  of 
  this 
  memoir, 
  invariably 
  local. 
  

  

  Age, 
  thickness, 
  8fc. 
  — 
  The 
  Vindhyans 
  in 
  this 
  area 
  are 
  remarkable 
  for 
  

   being 
  more 
  uniform 
  lithologically 
  than 
  in 
  other 
  parts. 
  The 
  lower 
  series, 
  

   composed 
  mainly 
  of 
  limestone 
  and 
  shale, 
  is 
  entirely 
  absent 
  ; 
  and 
  Mr. 
  

   Mallet 
  is 
  apparently 
  rather 
  doubtful 
  as 
  to 
  which 
  of 
  the 
  three 
  groups 
  

   of 
  the 
  upper 
  series 
  (Bhanrer, 
  Rewah, 
  and 
  Kaimur) 
  the 
  rocks 
  here 
  should 
  

   be 
  referred. 
  He 
  suggests 
  the 
  possibility 
  of 
  their 
  including 
  both 
  the 
  

   Rewahs 
  and 
  Kaimurs, 
  though 
  the 
  two 
  are 
  no 
  longer 
  distinguishable. 
  1 
  

  

  They 
  form 
  a 
  shallow 
  synclinal. 
  A 
  thick-bedded 
  sandstone 
  is 
  never 
  

   missed 
  at 
  the 
  base. 
  It 
  is 
  especially 
  well 
  seen 
  on 
  a 
  hill 
  (called 
  Tengria- 
  

   pahar), 
  a 
  mile 
  north-east 
  of 
  Jhirpania, 
  in 
  the 
  Dhar 
  forest. 
  Here 
  mas- 
  

   sive 
  beds 
  of 
  sandstone, 
  each 
  averaging 
  some 
  8 
  feet 
  in 
  thickness, 
  rest 
  with 
  

   marked 
  unconformity 
  upon 
  the 
  Bijawars. 
  As 
  thickness 
  of 
  stratification 
  

   has 
  been 
  noted 
  as 
  a 
  characteristic 
  feature 
  of 
  the 
  Kaimur 
  sandstone, 
  the 
  

   sandstone 
  in 
  question 
  probably 
  represents 
  it. 
  The 
  higher 
  beds 
  may 
  be 
  

   referable 
  to 
  the 
  Rewah 
  group 
  ; 
  and 
  Mr. 
  Mallet 
  finds 
  in 
  the 
  overlying 
  

   shales 
  " 
  considerable, 
  though, 
  not 
  a 
  strong, 
  resemblance 
  to 
  those 
  at 
  Gun- 
  

   noorgur, 
  more 
  to 
  the 
  eastward/' 
  and 
  considers 
  it 
  possible 
  that 
  they 
  

  

  1 
  *' 
  Memoirs," 
  Vol. 
  VI 
  \, 
  pp. 
  55, 
  78, 
  98. 
  

  

  ( 
  19 
  ) 
  

  

  