﻿58 
  BOSE 
  : 
  GEOLOGY 
  OF 
  THE 
  LOWER 
  NARBADA 
  VALLEY. 
  

  

  some 
  of 
  their 
  beds, 
  tearing 
  off 
  and 
  scattering 
  broadcast 
  angular 
  blocks 
  

   derived 
  from 
  them. 
  

  

  At 
  Malpur, 
  between 
  Karajwani 
  and 
  Temrio, 
  by 
  the 
  road 
  to 
  Dei, 
  

   there 
  occur 
  masses 
  of 
  crystalline 
  dolerite 
  weathering 
  into 
  large-sized 
  

   exfoliating 
  nodules. 
  They 
  are 
  exposed 
  only 
  for 
  a 
  few 
  yards, 
  and 
  are 
  lost 
  

   under 
  beds 
  of 
  Nimar 
  sandstone 
  and 
  upper 
  cretaceous 
  limestone, 
  the 
  

   sandstone 
  close 
  to 
  the 
  junction 
  being 
  altered 
  into 
  quartzite. 
  The 
  surface 
  

   of 
  the 
  sedimentary 
  rock 
  in 
  immediate 
  contact 
  here 
  (and 
  in 
  a 
  few 
  other 
  

   cases) 
  has 
  been 
  smoothed 
  and 
  scratched 
  with 
  parallel 
  grooves 
  as 
  if 
  by 
  

   faulting. 
  But 
  there 
  was 
  no 
  other 
  sign 
  of 
  any 
  such 
  dislocation 
  noticeable 
  

   in 
  any 
  of 
  these 
  cases 
  ; 
  and 
  the 
  striation 
  of 
  the 
  contact 
  surface 
  appears 
  to 
  

   have 
  been 
  produced 
  somehow 
  subsequent 
  to 
  its 
  fusion 
  or 
  semi-fusion 
  by 
  

   the 
  heat 
  of 
  the 
  intruded 
  rock. 
  

  

  About 
  a 
  mile 
  westward, 
  south-west 
  of 
  Karajwani, 
  there 
  runs 
  in 
  an 
  

   east-north-east 
  — 
  west-south-west 
  direction, 
  almost 
  in 
  a 
  line 
  with 
  the 
  

   doleritic 
  dyke 
  just 
  noticed, 
  another 
  of 
  rather 
  compact, 
  fine-grained 
  

   dolerite 
  l 
  exposed 
  to 
  observation 
  with 
  trifling 
  interruptions 
  for 
  over 
  three- 
  

   quarters 
  of 
  a 
  mile. 
  The 
  sandstones 
  immediately 
  in 
  contact 
  have 
  been 
  

   variously, 
  and 
  as 
  if 
  whimsically, 
  altered. 
  The 
  alteration, 
  however, 
  does 
  

   not 
  extend 
  beyond 
  half 
  a 
  foot 
  in 
  any 
  direction 
  ; 
  nor 
  are 
  there 
  any 
  signs 
  

   of 
  disturbance 
  in 
  the 
  uplifted 
  strata. 
  

  

  At 
  Narjuli, 
  east 
  of 
  Malpur, 
  there 
  is 
  a 
  dyke 
  running 
  as 
  a 
  ridge, 
  

   with 
  yellowish, 
  baked, 
  pre-trappean 
  rocks 
  at 
  its 
  summit. 
  

  

  These 
  three 
  dykes 
  are 
  almost 
  in 
  a 
  line 
  and 
  probably 
  connected 
  under- 
  

   ground. 
  At 
  Chaklio, 
  2 
  miles 
  north 
  of 
  Dei, 
  a 
  small 
  dyke 
  of 
  basalt 
  is 
  

   exposed, 
  and 
  I 
  have 
  no 
  doubt 
  several 
  similar 
  ones 
  occur 
  in 
  the 
  district. 
  

  

  At 
  Phata, 
  at 
  the 
  northern 
  extremity 
  of 
  the 
  Dei 
  area, 
  a 
  dyke 
  is 
  cut 
  

   through 
  by 
  the 
  Hatni. 
  It 
  is 
  of 
  a 
  coarsely 
  crystalline 
  rock, 
  similar 
  to 
  that 
  

   of 
  Mandlesar, 
  Barwani, 
  Malpur, 
  &c, 
  passing 
  above 
  and 
  at 
  the 
  sides 
  into 
  

   a 
  much 
  finer 
  grained 
  dolerite. 
  The 
  sandstones 
  in 
  contact 
  are 
  remarkably 
  

   altered. 
  

  

  The 
  cretaceous 
  tract 
  west 
  of 
  Dei 
  has 
  been 
  broken 
  through 
  by 
  innumer- 
  

  

  1 
  The 
  rock 
  is 
  so 
  named 
  from 
  its 
  crystalline 
  structure 
  as 
  seen 
  under 
  the 
  microscope. 
  To 
  

   the 
  naked 
  eye 
  it, 
  like 
  several 
  other 
  dyke-rocks, 
  appears 
  a 
  basalt. 
  

  

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