﻿APR. 
  4, 
  1922 
  brouwer: 
  tectonic 
  features 
  dutch 
  east 
  indies 
  175 
  

  

  tive 
  tectonics, 
  embryotectonics, 
  and 
  comparative 
  embryotectonics, 
  as 
  

   in 
  zoology 
  comparative 
  anatomy 
  and 
  ontogeny 
  are 
  essential 
  parts 
  of 
  

   morphology. 
  

  

  The 
  tectonic 
  features 
  of 
  the 
  East 
  Indian 
  Archipelago 
  as 
  they 
  now 
  

   exist 
  are 
  the 
  result 
  of 
  orogenic 
  forces 
  which 
  have 
  been 
  acting 
  during 
  

   long 
  periods 
  of 
  time 
  and 
  which 
  have 
  caused 
  movements 
  in 
  a 
  horizontal 
  

   direction 
  at 
  many 
  places. 
  Where 
  the 
  lands 
  were 
  high 
  above 
  the 
  

   strand-lines 
  of 
  the 
  surrounding 
  seas, 
  the 
  ranges 
  were 
  cut 
  down 
  and 
  the 
  

   deeper 
  parts 
  were 
  uncovered 
  by 
  erosion; 
  where 
  at 
  the 
  same 
  time 
  the 
  

   crust 
  was 
  moving 
  below 
  sea-level 
  no 
  denudation 
  took 
  place 
  and 
  no 
  un- 
  

   conformities 
  or 
  disconformities 
  in 
  the 
  succession 
  of 
  strata 
  are 
  found. 
  

   In 
  the 
  parts 
  of 
  the 
  earth's 
  crust, 
  which 
  are 
  now 
  visible 
  on 
  the 
  different 
  

   islands 
  the 
  erosion 
  intervals 
  are 
  not 
  found 
  at 
  the 
  same 
  place 
  in 
  the 
  

   geological 
  time-table. 
  In 
  Sumatra 
  a 
  striking 
  unconformity 
  is 
  found 
  

   between 
  the 
  late 
  Mesozoic 
  and 
  the 
  early 
  Tertiary, 
  in 
  Timor 
  between 
  

   the 
  middle 
  Tertiary 
  and 
  the 
  Plio- 
  Pleistocene. 
  In 
  order 
  to 
  give 
  a 
  

   detailed 
  account 
  of 
  the 
  tectonic 
  features 
  it 
  would 
  be 
  necessary 
  to 
  de- 
  

   scribe 
  the 
  many 
  islands 
  separately 
  but 
  for 
  the 
  major 
  tectonic 
  features 
  

   it 
  is 
  sufficient 
  to 
  describe 
  the 
  visible 
  traces 
  of 
  two 
  stages 
  of 
  crustal 
  

   movements, 
  the 
  late 
  Mesozoic 
  and 
  Tertiary 
  stage 
  and 
  the 
  youngest 
  

   stage, 
  which 
  still 
  continues. 
  The 
  youngest 
  stage 
  is 
  definitely 
  known 
  

   to 
  he 
  limited 
  to 
  certain 
  parts 
  of 
  the 
  present 
  Archipelago, 
  while 
  the 
  dis- 
  

   tribution 
  in 
  time 
  and 
  place 
  of 
  the 
  older 
  stage 
  is 
  not 
  exactly 
  known. 
  

  

  THE 
  OLDER 
  TREND 
  LINES 
  STUDIED 
  IN 
  PLAN 
  

  

  Digitate 
  forms, 
  such 
  as 
  those 
  represented 
  by 
  the 
  islands 
  Celebes 
  and 
  

   Halmaheira 
  have 
  been 
  considered 
  as 
  produced 
  by 
  a 
  broad 
  side- 
  and 
  end- 
  

   on 
  conflict 
  of 
  Tertiary 
  folded 
  ranges. 
  See 
  Fig. 
  1 
  . 
  Yet 
  it 
  can 
  be 
  shown 
  

   that 
  the 
  present 
  morphology 
  is 
  the 
  result 
  of 
  the 
  youngest 
  stage 
  of 
  

   crustal 
  movements, 
  since 
  the 
  known 
  strike 
  of 
  the 
  Tertiary 
  folds 
  is 
  in 
  

   places 
  very 
  different 
  from 
  the 
  direction 
  of 
  the 
  present 
  geanticlines. 
  

   In 
  the 
  eastern 
  peninsula 
  of 
  Celebes 
  a 
  northwest-southeast 
  or 
  north 
  

   northwest-south-southeast 
  strike 
  is 
  found 
  in 
  strongly 
  folded 
  marls 
  and 
  

   limestones 
  with 
  associated 
  layers 
  and 
  nodules 
  of 
  hornstone. 
  In 
  the 
  

   eastern 
  part 
  of 
  this 
  peninsula 
  the 
  central 
  range 
  consists 
  of 
  nearly 
  

   horizontal 
  limestones 
  of 
  Eocene 
  and 
  Oligocene 
  age. 
  On 
  the 
  northern 
  

   and 
  southern 
  slopes 
  more 
  or 
  less 
  pronounced 
  dips 
  to 
  the 
  northwest 
  have 
  

   been 
  found. 
  In 
  the 
  central 
  part 
  of 
  the 
  island 
  the 
  main 
  Tertiary 
  strike 
  

   seems 
  to 
  be 
  northwest-southeast. 
  The 
  tectonic 
  features 
  of 
  the 
  south- 
  

   eastern 
  peninsula 
  of 
  Celebes 
  are 
  but 
  little 
  known, 
  its 
  northern 
  part 
  

  

  