﻿100 
  THEOBALD 
  : 
  GEOLOGY 
  OF 
  PEGU. 
  

  

  This 
  section, 
  though 
  not 
  everywhere 
  well 
  exposed, 
  and 
  lying* 
  in 
  a 
  

   small 
  and 
  somewhat 
  tortuous 
  stream, 
  gives, 
  nevertheless, 
  a 
  good 
  general 
  

   idea 
  of 
  the 
  beds 
  of 
  the 
  Nummulitie 
  group, 
  and 
  may 
  be 
  thus 
  generalized 
  : 
  

  

  Miocene. 
  

  

  Clay 
  and 
  sandstones 
  

  

  NuMMULITIC. 
  

  

  1. 
  Nummulitie 
  limestone,.. 
  ... 
  ... 
  ... 
  10 
  

  

  2. 
  Shales 
  and 
  sandstones 
  j 
  shales 
  occasionally 
  Nummulitie 
  ... 
  658 
  

  

  3. 
  Massive 
  sandstones 
  with 
  some 
  shales 
  and 
  much 
  soda 
  

  

  efflorescence 
  in 
  places 
  ... 
  ... 
  ... 
  328 
  

  

  4. 
  Shales 
  and 
  sandstones, 
  the 
  shale 
  with 
  some 
  carhonaceous 
  

  

  ... 
  227 
  

  

  Total 
  ...1,223 
  

  

  The 
  limestone 
  at 
  the 
  head 
  of 
  this 
  section 
  is, 
  as 
  far 
  as 
  can 
  be 
  

   judged, 
  the 
  highest 
  bed 
  of 
  the 
  Nummulitie 
  group 
  : 
  and 
  its 
  variable- 
  

   thickness, 
  for 
  in 
  many 
  places 
  it 
  must 
  be 
  from 
  sixty 
  to 
  a 
  hundred 
  feet 
  

   thick, 
  is 
  quite 
  in 
  accordance 
  with 
  that 
  general 
  irregularity 
  of 
  develop- 
  

   ment 
  which, 
  as 
  I 
  have 
  already 
  described, 
  causes 
  it 
  in 
  places 
  to 
  thin 
  

   out 
  abruptly 
  and 
  disappear. 
  There 
  can, 
  however, 
  be 
  little 
  doubt 
  that 
  

   this 
  topmost 
  bed 
  of 
  the 
  group 
  is 
  the 
  same 
  bed 
  which 
  can 
  be 
  traced 
  

   at 
  intervals 
  from 
  near 
  Phoungyi 
  to 
  the 
  Pyengma 
  stream 
  in 
  the 
  Bassein 
  

   district, 
  a 
  distance 
  in 
  a 
  direct 
  line 
  of 
  two 
  hundred 
  and 
  twenty 
  -four 
  miles. 
  

   That 
  it 
  is 
  not 
  more 
  largely 
  met 
  with 
  than 
  it 
  is, 
  seems 
  partly 
  attribut- 
  

   able 
  to 
  its 
  irregular 
  development, 
  and 
  partly 
  no 
  doubt 
  to 
  the 
  extensive 
  

   denudation 
  it 
  has 
  undergone 
  during 
  the 
  most 
  recent 
  times 
  and 
  subse- 
  

   quent 
  to 
  the 
  formation 
  and 
  arrangement 
  of 
  the 
  general 
  surface 
  features 
  

   of 
  the 
  ground 
  at 
  present. 
  Below 
  the 
  bed 
  in 
  the 
  above 
  section 
  there 
  comes 
  

   in 
  a 
  great 
  thickness 
  of 
  sandstone 
  and 
  shales, 
  which 
  are 
  perhaps 
  best 
  seen 
  

   in 
  the 
  pass 
  East 
  of 
  Mendoon; 
  but 
  I 
  did 
  not 
  measure 
  the 
  beds, 
  

   as 
  I 
  saw 
  no 
  means 
  of 
  correlating 
  them 
  satisfactorily 
  with 
  the 
  above 
  

   section. 
  The 
  low 
  hills 
  Southwest 
  of 
  Choungkwa 
  on 
  the 
  Mahton 
  

   ( 
  288 
  ) 
  

  

  