432  PBE-CAMBRIAN    GEOLOGY   OF   NORTH    AMERICA. 
in  the  township  of  Marter,  to  the  Height  of  Land  north  of  Opazatica 
or  Long  Lake.  There  is  evidence  that  its  trend  there  becomes  more 
easterly  and  that  it  follows  the  great  Height  of  Land  ridge  farther 
into  Quebec.  The  southeasterly  limit  of  the  belt  is  approximately  a 
line  from  the  south  end  of  Fish  Lake,  on  the  international  boundary, 
to  a  little  beyond  the  northeast  angle  of  the  township  of  Ingram. 
Young,63  in  1905,  reports  on  the  area  between  Rabbit  and  Tema- 
gami  lakes.  The  geological  succession  is  similar  to  that  in  the  North- 
east Arm  of  Lake  Temagami.  The  oldest  series  of  rocks  consists 
chiefly  of  schists,  which  in  one  area  are  mainly  chloritic  and  sericitic, 
while  in  a  second  area  hornblende  and  mica  schists  predominate. 
These  schists  are  penetrated  by  masses  of  granite  of  at  least  two  varie- 
ties, one  of  which  is  also  cut  by  a  body  of  syenite.  The  schists  and 
intrusive  masses  of  granite  and  syenite  are  in  places  unconformably 
overlain  by  a  heavy  conglomerate,  which  almost  invariably  grades 
up  into  a  slate,  and  the  latter  in  one  instance  is  conformably  overlain 
by  a  bed  of  quartzite.  The  beds  of  slate  and  conglomerate  as  a  whole 
occur  horizontally  and  are  frequently  capped  by  sills  of  diabase. 
The  diabase  is  also  found  resting  on  the  schists  and  granites.  Dia- 
base dikes  intersect  the  schists,  the  granites,  and  the  overlying  con- 
glomerate and  slate  formation;  their  relation  to  the  sheets  of  diabase 
was  not  observed. 
Coleman,04  in  1905,  describes  and  maps  the  geology  of  the  Sudbury 
nickel  basin  of  Ontario.     His  sedimentary  succession  is  as  follows: 
Later Upper  Huronian-Animikie_. 
Chelmsford  sandstone. 
( hiwatin  slate. 
Onaping  tuff. 
Trout  Lake  conglomerate. 
[Middle  Iluronian Ramsay  Lake  conglomerate. 
ArcheanJ  Tx  .  [Quartzite. 
Lower  Huronian I  „  ,  ,    ,   J 
[Graywacke  and  slate. 
Intrusive  into  the  rocks  of  the  Lower  and  Middle  Huronian  are 
acidic  and  basic  eruptives  consisting  of  altered  diabases,  porphyrites, 
norite,  gabbro,  and  granite.  Also  intrusive  are  other  granites  and 
gneisses  assigned  to  the  Laurentian.  Between  the  Animikie  and  the 
lower  sediments  there  is  intruded  a  laccolithic  mass,  the  folding  of 
which  is  such  that  it  constitutes  a  boat-shaped  basin  carrying  the 
Animikie  within  it.  Its  average  thickness  is  1J  miles.  The  outer 
edge  of  this  eruptive  is  basic  and  carries  the  nickel  deposits.  Toward 
the  inner  edge  there  is  a  gradation  into  acidic  rocks.  The  ores  are 
believed  to  be  the  result  of  magmatic  separation,  modified  by  later 
solution  and  redeposition. 
Miller,65  in  1905,  makes  a  report  upon  the  Boston  Township  iron 
range  of  northeastern  Ontario.  The  range  consists  of  iron- formation 
bands  and  lenses  associated  with  Keewatin  greenstones  and  green 
