﻿Vol. 
  53.] 
  STJDBDTEY 
  STICKEL 
  DISTEICT 
  (CANADA). 
  41 
  

  

  in 
  the 
  cuttings 
  of 
  the 
  Canadian 
  Pacific 
  Railway 
  in 
  the 
  neighbour- 
  

   hood 
  of 
  Sudbury. 
  During 
  the 
  seasons 
  of 
  1888, 
  '89, 
  and 
  '90, 
  Bell 
  and 
  

   Barlow 
  were 
  appointed 
  by 
  the 
  Canadian 
  Geological 
  Survey 
  to 
  explore 
  

   the 
  district. 
  A 
  collection 
  of 
  rocks 
  was 
  sent 
  by 
  Bell 
  to 
  the 
  late 
  

   G. 
  H. 
  Williams, 
  whose 
  petrographical 
  studies 
  were 
  published 
  along 
  

   with 
  Bell's 
  report. 
  During 
  the 
  summer 
  of 
  1890 
  the 
  late 
  Baron 
  von 
  

   JFoullon, 
  of 
  the 
  Austrian 
  Geological 
  Survey, 
  spent 
  a 
  few 
  weeks 
  in 
  

   the 
  district, 
  and 
  directed 
  his 
  attention 
  particularly 
  to 
  the 
  determi- 
  

   nation 
  of 
  the 
  relative 
  ages 
  of 
  the 
  different 
  rocks. 
  A 
  full 
  statement 
  

   of 
  the 
  literature 
  bearing 
  on 
  the 
  subject 
  is 
  appended 
  (§ 
  VIII. 
  p. 
  65). 
  

   I 
  beg 
  to 
  acknowledge 
  my 
  indebtedness 
  to 
  the 
  writings 
  of 
  all 
  who 
  

   have 
  studied 
  the 
  geology 
  of 
  the 
  Sudbury 
  district, 
  especially 
  to 
  the 
  

   papers 
  of 
  Adams, 
  Bell, 
  Barlow, 
  Bonney, 
  von 
  Poullon, 
  Garnier, 
  and 
  

   G. 
  H. 
  Williams. 
  Vogt's 
  excellent 
  descriptions 
  of 
  the 
  Norwegian 
  

   nickel-deposits 
  and 
  associated 
  rocks 
  have 
  been 
  freely 
  consulted, 
  as 
  

   in 
  many 
  respects 
  these 
  descriptions 
  are 
  quite 
  accurate 
  when 
  applied 
  

   to 
  the 
  Sudbury 
  district. 
  

  

  The 
  nickel 
  district 
  is 
  included 
  in 
  the 
  great 
  belt 
  of 
  Huronian 
  rocks 
  

   which 
  extends 
  from 
  the 
  northern 
  shore 
  of 
  Lake 
  Huron 
  north-east- 
  

   ward 
  to 
  Lake 
  Mistassini. 
  In 
  the 
  neighbourhood 
  of 
  Sudbury 
  this 
  

   belt 
  is 
  barely 
  25 
  miles 
  wide, 
  and 
  consists 
  of 
  quartzite, 
  amphibolite, 
  

   mica-schist, 
  phyllite, 
  volcanic 
  breccia, 
  and 
  grauwacke. 
  Inliers 
  of 
  

   later 
  eruptives 
  form 
  a 
  large 
  part 
  of 
  the 
  belt, 
  and 
  it 
  is 
  in 
  connexion 
  

   with 
  one 
  class 
  of 
  these 
  that 
  the 
  nickel-deposits 
  occur. 
  The 
  country 
  

   north-west 
  and 
  south-east 
  of 
  the 
  belt 
  of 
  Huronian 
  rocks 
  is 
  com- 
  

   posed 
  of 
  coarse 
  granites 
  and 
  gneisses 
  which 
  are 
  regarded 
  as 
  of 
  

   Laurentian 
  age. 
  

  

  The 
  whole 
  of 
  this 
  part 
  of 
  Canada 
  has 
  been 
  subjected 
  to 
  glacial 
  

   action, 
  the 
  general 
  direction 
  of 
  ice-movement 
  having 
  been 
  from 
  

   north-east 
  to 
  south-west. 
  The 
  rocks 
  in 
  many 
  places 
  present 
  well- 
  

   polished 
  surfaces, 
  particularly 
  where 
  the 
  protecting 
  covering 
  of 
  

   clay, 
  sand, 
  or 
  gravel 
  has 
  been 
  only 
  recently 
  removed, 
  as 
  in 
  railway- 
  

   cuttings 
  and 
  along 
  lake- 
  and 
  river-banks. 
  The 
  most 
  lasting 
  work 
  

   of 
  glacial 
  agency 
  is. 
  seen 
  in 
  the 
  hollowing-out 
  of 
  innumerable 
  

   depressions, 
  which 
  are 
  now 
  occupied 
  by 
  lakes 
  and 
  rivers. 
  Archaean 
  

   districts 
  in 
  Canada 
  are 
  characterized 
  by 
  innumerable 
  rocky 
  lakes 
  

   with 
  clear 
  waters 
  and 
  swift 
  eddying 
  streams. 
  

  

  II. 
  The 
  Gneiss-Foemation". 
  

  

  The 
  larger 
  part 
  of 
  Northern 
  Ontario 
  is 
  occupied 
  by 
  gneisses 
  of 
  

   various 
  kinds. 
  In 
  the 
  immediate 
  vicinity 
  of 
  Sudbury 
  these 
  rocks 
  

   are 
  not 
  observed, 
  though 
  they 
  form 
  almost 
  endless 
  tracts 
  on 
  both 
  

   sides 
  of 
  the 
  Huronian 
  belt. 
  Good 
  exposures, 
  which 
  are 
  easily 
  

   reached, 
  occur 
  in 
  the 
  cuttings 
  of 
  the 
  Canadian 
  Pacific 
  Railway, 
  near 
  

   Wahnapitae 
  to 
  the 
  south-east, 
  and 
  about 
  3 
  miles 
  west 
  of 
  Onaping 
  

   to 
  the 
  north-west. 
  Besides 
  these 
  gneisses, 
  which 
  may 
  be 
  regarded 
  

   as 
  Laurentian, 
  there 
  are 
  gneissoid 
  rocks 
  geographically 
  included 
  in 
  

   the 
  Huronian 
  belt, 
  but 
  as 
  these 
  are 
  of 
  very 
  much 
  later 
  origin, 
  and 
  

   not 
  true 
  gneisses, 
  it 
  is 
  proposed 
  to 
  deal 
  with 
  them 
  in 
  a 
  later 
  section. 
  

  

  