﻿136 
  THEOBALD 
  : 
  GEOLOGY 
  OF 
  PEGU. 
  

  

  baiahn 
  hill. 
  An 
  outcrop 
  of 
  this 
  rock 
  also 
  occurs 
  near 
  the 
  Mahton, 
  about 
  

   one 
  mile 
  North-west 
  of 
  Lepangaing, 
  where 
  it 
  appears 
  to 
  strike 
  West-south- 
  

   west, 
  and 
  three 
  miles 
  North-east 
  of 
  this 
  outcrop 
  is 
  a 
  large 
  patch 
  of 
  lime- 
  

   stone 
  forming 
  a 
  low 
  hill, 
  the 
  dip 
  not 
  being 
  well 
  seen, 
  whilst 
  two 
  and 
  a 
  half 
  

   miles 
  South 
  of 
  the 
  first 
  outcrop 
  is 
  another 
  large 
  mass 
  of 
  limestone 
  which 
  

   forms 
  the 
  summit 
  of 
  a 
  hill. 
  The 
  ascent 
  to 
  this 
  last 
  mass 
  of 
  limestone 
  

   lies 
  over 
  typical 
  upper 
  Axial 
  strata, 
  and 
  I 
  believe 
  all 
  these 
  three 
  outcrops 
  

   belong 
  to 
  one 
  and 
  the 
  same 
  bed. 
  Although 
  the 
  limestone 
  would 
  here 
  

   seem 
  to 
  be 
  more 
  developed 
  than 
  farther 
  to 
  the 
  South, 
  I 
  noticed 
  no 
  

   fossils 
  in 
  it, 
  which 
  is, 
  I 
  think, 
  due 
  to 
  the 
  greater 
  amount 
  of 
  alteration 
  

   the 
  rock 
  has 
  here 
  undergone. 
  At 
  various 
  other 
  spots 
  traces 
  occur 
  of 
  

   this 
  bed, 
  but 
  nowhere 
  has 
  it 
  yielded 
  fossils 
  capable 
  of 
  determination 
  

   (save 
  at 
  one 
  spot), 
  and 
  that 
  only 
  the 
  single 
  species 
  of 
  Halobia 
  above 
  

   named. 
  

  

  Whilst, 
  therefore, 
  this 
  limestone 
  is 
  the 
  only 
  bed 
  of 
  the 
  group 
  which 
  has 
  

   yielded 
  any 
  reliable 
  evidence 
  of 
  its 
  age, 
  meagre 
  as 
  that 
  evidence 
  is, 
  the 
  

   next 
  division 
  (<?) 
  of 
  the 
  group 
  is 
  the 
  most 
  important 
  as 
  regards 
  the 
  pecu- 
  

   liar 
  petrological 
  character 
  of 
  its 
  beds, 
  which 
  enable 
  us 
  to 
  recognise 
  them 
  

   with 
  confidence 
  wherever 
  met 
  with. 
  The 
  characteristic 
  beds 
  of 
  this 
  

   division, 
  which 
  embraces 
  over 
  thirteen 
  hundred 
  feet 
  of 
  beds, 
  are 
  white 
  

   freckled 
  grits 
  and 
  conglomerates, 
  not 
  usually 
  very 
  coarse 
  (though 
  here 
  

   and 
  there 
  coarse 
  beds, 
  almost 
  pseudo-breccias, 
  occur), 
  and 
  cream-colored 
  

   argillaceous 
  sandstones, 
  often 
  having 
  a 
  sub-porcellaneous 
  appearance, 
  or 
  

   sometimes 
  something 
  of 
  a 
  lithographic 
  look. 
  Small 
  white 
  quartz 
  pebbles 
  

   abound 
  in 
  the 
  finer 
  conglomerates, 
  but 
  the 
  coarser 
  conglomerates 
  are 
  

   mainly 
  composed 
  of 
  argillaceous 
  subschistose 
  rocks, 
  which 
  suggest 
  the 
  

   idea 
  of 
  their 
  being 
  derived 
  from 
  beds 
  of 
  the 
  lower 
  division 
  of 
  the 
  group, 
  

   though 
  this 
  is 
  probably 
  fallacious. 
  The 
  coarsest 
  beds 
  I 
  have 
  anywhere 
  

   noticed 
  occur 
  in 
  the 
  Shu 
  (Shoo) 
  stream 
  above 
  Sabatan. 
  In 
  the 
  lower 
  

   part 
  of 
  the 
  Shu, 
  an 
  enormous 
  thickness 
  of 
  beds 
  is 
  fairly 
  exposed, 
  but 
  

   greatly 
  disturbed 
  and 
  faulted 
  towards 
  the 
  boundary 
  of 
  the 
  group. 
  

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