﻿Vol. 
  53-] 
  

  

  SUPERFICIAL 
  DEPOSITS 
  IN 
  CTJTCH. 
  

  

  235 
  

  

  them. 
  It 
  will 
  be 
  seen 
  that, 
  beyond 
  calling 
  some 
  of 
  the 
  rocks 
  ' 
  ? 
  ashy 
  ' 
  

   and 
  ' 
  trappoid 
  ' 
  and 
  speaking 
  of 
  ' 
  trappean 
  blotches,' 
  the 
  author 
  

   speaks 
  of 
  nothing 
  but 
  grits. 
  It 
  is 
  true 
  that 
  in 
  some 
  parts 
  they 
  are 
  so 
  

   much 
  and 
  so 
  irregularly 
  discoloured, 
  apparently 
  by 
  infiltration, 
  that 
  

   they 
  then 
  bear 
  a 
  superficial 
  resemblance 
  to 
  some 
  rocks 
  of 
  volcanic 
  

   origin, 
  but 
  their 
  essentially 
  gritty 
  nature 
  is 
  unaltered. 
  

  

  The 
  best 
  exposure 
  is 
  on 
  the 
  northern 
  slope 
  of 
  the 
  hill, 
  where 
  the 
  

   section 
  shown 
  in 
  fig. 
  3 
  is 
  seen. 
  Here 
  the 
  bulk 
  of 
  the 
  hill 
  is 
  corn- 
  

  

  Fig. 
  3. 
  — 
  Infratrappean 
  grits 
  at 
  Bliujia 
  Hill. 
  

  

  

  A 
  = 
  Jurassic 
  rocks. 
  

  

  B 
  = 
  Infratrappean 
  grits. 
  

  

  C 
  = 
  Trap. 
  

  

  posed 
  of 
  the 
  Jurassic 
  sandstones, 
  which 
  on 
  the 
  western 
  side 
  rise 
  

   up 
  and 
  meet 
  the 
  capping 
  of 
  basalt. 
  East 
  of 
  this 
  junction 
  there 
  

   comes 
  in 
  rapidly 
  a 
  series 
  of 
  thick 
  beds 
  of 
  very 
  porous 
  character, 
  

   all 
  of 
  which 
  are 
  laminated, 
  but 
  not 
  conformably 
  to 
  the 
  base 
  on 
  

   which 
  they 
  lie. 
  Their 
  porous 
  character 
  gives 
  them 
  a 
  very 
  ' 
  ashy 
  ' 
  

   appearance 
  — 
  that 
  is, 
  the 
  appearance 
  of 
  fine 
  debris 
  deposited 
  in 
  the 
  

   open 
  air; 
  but 
  they 
  are 
  almost 
  entirely 
  composed 
  of 
  sand-grains 
  

   lying 
  in 
  a 
  loose 
  matrix 
  of 
  finer 
  dust, 
  and 
  are 
  so 
  like 
  some 
  of 
  

   the 
  samples 
  of 
  subreceht 
  concrete 
  that 
  without 
  labels 
  they 
  can 
  

   scarcely 
  be 
  distinguished 
  in 
  hand-specimens. 
  The 
  laminae 
  run 
  up 
  

   to 
  and 
  meet 
  the 
  basalt 
  above, 
  and 
  as 
  we 
  pass 
  eastward 
  the 
  deposit 
  

   becomes 
  thinner 
  till 
  the 
  basalt 
  and 
  Jurassic 
  sandstones 
  come 
  together 
  

   again. 
  The 
  other 
  patches 
  referred 
  to 
  as 
  lying 
  in 
  the 
  open 
  hollows 
  

   are 
  generally 
  darker 
  and 
  more 
  compact, 
  but 
  they 
  are 
  still 
  sandy. 
  

   The 
  isolation 
  of 
  this 
  and 
  similar 
  deposits 
  at 
  Khirgreea 
  and 
  Rhojla 
  ; 
  

   its 
  occurrence 
  in 
  a 
  shelter-spot 
  on 
  an 
  old 
  Jurassic 
  hill 
  ; 
  its 
  porous 
  

   character 
  and 
  sandy 
  composition, 
  all 
  point 
  to 
  an 
  seolian 
  origin, 
  

   representing 
  as 
  they 
  do 
  the 
  same 
  conditions 
  as 
  those 
  represented 
  by 
  

   the 
  subrecent 
  concrete. 
  

  

  The 
  second 
  type 
  of 
  deposit 
  at 
  Sanosra, 
  due 
  south 
  of 
  Bhuj, 
  and 
  

   at 
  Artara, 
  between 
  the 
  Jurassic 
  rocks 
  and 
  the 
  trap, 
  is 
  simply 
  a 
  

   collection 
  of 
  stones 
  derived 
  from 
  the 
  rocks 
  below, 
  cemented 
  by 
  finer 
  

   material, 
  and 
  lying 
  in 
  hollows 
  over 
  which 
  the 
  trap 
  passes 
  : 
  that 
  is 
  

   to 
  say, 
  it 
  is 
  the 
  surface-debris 
  of 
  the 
  land 
  on 
  which 
  the 
  lava 
  was 
  

   poured 
  out. 
  

  

  r2 
  

  

  