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  53'] 
  THE 
  SUPERFICIAL 
  DEPOSITS 
  OF 
  CUTCH. 
  223 
  

  

  18. 
  On 
  some 
  Superficial 
  Deposits 
  in 
  Cutch. 
  By 
  the 
  Eev. 
  J. 
  F. 
  

   Blake, 
  M.A., 
  F.G.S. 
  (Bead 
  February 
  3rd, 
  1897.) 
  

  

  [Abridged. 
  1 
  ] 
  

  

  During- 
  a 
  recent 
  visit 
  to 
  Cutcb 
  for 
  the 
  purpose 
  of 
  studying 
  the 
  

   Jurassic 
  2 
  rocks 
  there 
  exposed, 
  my 
  attention 
  was 
  naturally 
  attracted 
  

   to 
  a 
  number 
  of 
  superficial 
  deposits, 
  which 
  in 
  some 
  cases 
  concealed, 
  

   and 
  in 
  others 
  were 
  associated 
  with, 
  the 
  solid 
  rocks 
  beneath. 
  I 
  

   cannot 
  pretend 
  to 
  have 
  made 
  an 
  exhaustive 
  study 
  of 
  them, 
  as 
  I 
  have 
  

   only 
  examined 
  such 
  parts 
  as 
  may 
  be 
  found 
  in 
  the 
  Jurassic 
  area 
  ; 
  

   but 
  these 
  have 
  suggested 
  certain 
  theories 
  of 
  their 
  origin, 
  which 
  I 
  

   have 
  not 
  seen 
  proposed 
  elsewhere, 
  and 
  as 
  these 
  theories 
  depend 
  on 
  

   observations 
  which 
  I 
  do 
  not 
  find 
  recorded, 
  it 
  may 
  at 
  least 
  be 
  hoped 
  

   that 
  an 
  account 
  of 
  such 
  observations 
  may 
  throw 
  light 
  on 
  the 
  origin 
  

   of 
  the 
  deposits. 
  The 
  matters 
  with 
  which 
  I 
  propose 
  to 
  deal 
  may 
  be 
  

   classed 
  under 
  the 
  following 
  heads 
  : 
  — 
  

  

  (1) 
  Subrecent 
  concrete. 
  

  

  (2) 
  The 
  boulder-beds 
  associated 
  with 
  this 
  concrete. 
  

  

  (3) 
  Infratrappean 
  grits. 
  

  

  (4) 
  Laterite. 
  

  

  (5) 
  Alluvium 
  and 
  Ran. 
  

  

  Of 
  all 
  these, 
  except 
  No. 
  2, 
  there 
  are 
  to 
  be 
  found 
  brief 
  descrip- 
  

   tions 
  in 
  Mr. 
  A. 
  B. 
  Wynne's 
  memoir 
  on 
  the 
  geology 
  of 
  Cutch, 
  3 
  but, 
  

   as 
  a 
  rule, 
  that 
  author 
  does 
  not 
  venture 
  on 
  any 
  suggestion 
  as 
  to 
  their 
  

   origin, 
  and 
  in 
  no 
  case 
  does 
  he 
  appeal 
  to 
  the 
  particular 
  causes 
  to 
  

   which 
  I 
  have 
  been 
  led 
  to 
  refer 
  them. 
  

  

  (1) 
  The 
  Subrecent 
  Concrete. 
  

  

  Under 
  this 
  name 
  Mr. 
  Wynne 
  describes 
  some 
  remarkable 
  deposits 
  

   of 
  which 
  he 
  writes 
  as 
  follows 
  : 
  — 
  ' 
  Very 
  generally 
  distributed 
  over 
  

   the 
  hilly 
  country 
  is 
  the 
  subrecent 
  calcareous 
  deposit 
  already 
  alluded 
  

   to. 
  The 
  white 
  sandstones 
  of 
  which 
  it 
  consists 
  are 
  sometimes 
  

   sufficiently 
  coherent 
  to 
  be 
  used 
  for 
  building, 
  and 
  it 
  is 
  very 
  commonly 
  

   burnt 
  for 
  lime 
  all 
  over 
  the 
  province. 
  No 
  fossils 
  have 
  ever 
  been 
  

   found 
  in 
  it, 
  but 
  on 
  some 
  slabs 
  from 
  the 
  deposit 
  in 
  Western 
  Cutch 
  

   tracks 
  of 
  Crustacea 
  or 
  of 
  annelids 
  have 
  been 
  observed. 
  It 
  is 
  not 
  

   limited 
  to 
  a 
  uniform 
  level 
  in 
  its 
  various 
  situations, 
  having 
  been 
  met 
  

   with 
  in 
  the 
  low 
  ground 
  at 
  the 
  foot 
  of 
  the 
  hills 
  bordering 
  the 
  Eunn, 
  

   as 
  well 
  as 
  high 
  in 
  their 
  glens. 
  Its 
  aspect 
  is 
  always 
  very 
  much 
  the 
  

   same, 
  though 
  its 
  texture 
  is 
  varied, 
  being 
  sometimes 
  conglomeratic 
  or 
  

   finely 
  oolitic, 
  and 
  generally 
  it 
  presents 
  some 
  oblique 
  lamination.' 
  4 
  

  

  1 
  [By 
  the 
  omission 
  of 
  that 
  portion 
  of 
  the 
  paper 
  in 
  which 
  the 
  quartzite- 
  

   reefs 
  and 
  their 
  mode 
  of 
  formation 
  were 
  discussed.] 
  

  

  2 
  Throughout 
  this 
  memoir 
  I 
  use 
  the 
  word 
  'Jurassic' 
  for 
  all 
  the 
  rocks 
  so 
  

   coloured 
  on 
  Mr. 
  Wynne's 
  map, 
  without 
  prejudging 
  the 
  question 
  as 
  to 
  how 
  many 
  

   of 
  them 
  may 
  be, 
  as 
  some 
  certainly 
  are, 
  of 
  Neocoraian 
  age. 
  

  

  3 
  Mem. 
  Geol. 
  Surv. 
  India, 
  vol. 
  ix. 
  pt. 
  i. 
  (1872). 
  4 
  Ibid. 
  p. 
  81. 
  

  

  