﻿40 
  ME. 
  T. 
  L. 
  WALKER 
  OS 
  THE 
  [Feb. 
  1897, 
  

  

  4. 
  Geological 
  and 
  Petrographical 
  Studies 
  of 
  the 
  Sudbury 
  Nickel 
  

   District 
  (Canada). 
  By 
  T. 
  L. 
  Walker, 
  Esq., 
  M.A. 
  (Com- 
  

   municated 
  by 
  J. 
  J. 
  H. 
  Teall, 
  Esq., 
  M.A., 
  E.R.S., 
  Sec. 
  G.S, 
  

   Eead 
  November 
  4th, 
  1896.) 
  

  

  [Abridged.] 
  

  

  Contents. 
  

  

  Page 
  

  

  I. 
  Introduction 
  40 
  

  

  II. 
  The 
  G-neiss-Formation 
  41 
  

  

  III. 
  The 
  Huronian 
  Rocks 
  43 
  

  

  IV. 
  The 
  Nickel-bearing 
  Rocks 
  46 
  

  

  V. 
  Other 
  Nickeliferous 
  Areas 
  59 
  

  

  VI. 
  The 
  Younger 
  Granites 
  61 
  

  

  VII. 
  Olivine 
  -diabase 
  Dykes 
  62 
  

  

  VIII. 
  Literature 
  65 
  

  

  Map 
  64 
  

  

  I. 
  Introduction. 
  

  

  The 
  town 
  of 
  Sudbury 
  is 
  situated 
  in 
  Northern 
  Ontario, 
  442 
  miles- 
  

   from 
  Montreal 
  on 
  the 
  transcontinental 
  line 
  of 
  the 
  Canadian 
  Pacific 
  

   Railway. 
  When 
  this 
  railway 
  was 
  constructed 
  some 
  eight 
  or 
  ten 
  

   years 
  ago, 
  the 
  name 
  Sudbury 
  was 
  given 
  to 
  a 
  small 
  station 
  which 
  

   was 
  afterwards 
  selected 
  for 
  the 
  eastern 
  terminus 
  of 
  the 
  branch 
  

   railway 
  that 
  follows 
  the 
  northern 
  shore 
  of 
  Lake 
  Huron 
  and 
  crosses 
  

   the 
  St. 
  Mary 
  River 
  at 
  Sault 
  Ste. 
  Marie. 
  It 
  is 
  about 
  40 
  miles 
  from 
  

   the 
  north-eastern 
  shore 
  of 
  Lake 
  Huron. 
  

  

  Shortly 
  after 
  the 
  construction 
  of 
  the 
  railway, 
  considerable 
  deposits 
  

   of 
  chalcopyrite 
  were 
  discovered 
  in 
  the 
  neighbourhood, 
  and 
  an 
  

   American 
  company 
  was 
  organized 
  to 
  work 
  them. 
  Thus 
  it 
  was 
  that 
  

   Copper 
  Cliff 
  Mine 
  was 
  opened 
  up 
  for 
  copper, 
  although 
  along 
  with 
  

   the 
  chalcopyrite 
  large 
  quantities 
  of 
  nickeliferous 
  pyrrhotite 
  occurred. 
  

   The 
  pyrrhotite 
  was 
  considered 
  worthless, 
  as 
  it 
  was 
  not 
  known 
  to 
  

   contain 
  nickel 
  till 
  the 
  mine 
  had 
  been 
  in 
  operation 
  for 
  some 
  little 
  

   time, 
  and 
  sales 
  had 
  been 
  made 
  of 
  the 
  products. 
  After 
  the 
  accidental 
  

   discovery 
  of 
  the 
  value 
  of 
  the 
  pyrrhotite 
  as 
  a 
  nickel 
  ore, 
  there 
  was 
  

   much 
  prospecting 
  in 
  the 
  district 
  for 
  nickel-deposits. 
  This 
  con- 
  

   tinued 
  till 
  1891, 
  by 
  which 
  time 
  scores 
  of 
  nickel- 
  deposits 
  had 
  been 
  

   located. 
  At 
  that 
  time 
  the 
  world's 
  annual 
  consumption 
  of 
  metallic 
  

   nickel 
  was 
  not 
  more 
  than 
  1500 
  tons, 
  and 
  hence 
  it 
  was 
  a 
  more 
  diffi- 
  

   cult 
  task 
  to 
  dispose 
  of 
  nickel 
  properties 
  at 
  remunerative 
  prices 
  than 
  

   it 
  was 
  to 
  discover 
  them. 
  Eor 
  this 
  reason, 
  prospecting 
  for 
  nickel 
  

   was 
  abandoned 
  in 
  this 
  region, 
  though 
  it 
  is 
  quite 
  probable 
  that, 
  

   should 
  a 
  demand 
  for 
  larger 
  quantities 
  of 
  nickel 
  arise, 
  many 
  more 
  

   deposits 
  will 
  yet 
  be 
  discovered. 
  

  

  The 
  earliest 
  geological 
  descriptions 
  of 
  the 
  country 
  in 
  the 
  imme- 
  

   diate 
  vicinity 
  of 
  Sudbury 
  were 
  published 
  by 
  Selwyn 
  in 
  1884. 
  In 
  

   1888 
  Bonney 
  published 
  an 
  account 
  of 
  the 
  Huronian 
  rocks 
  exposed 
  

  

  