vanhisk.]  THE    GREAT    NORTHERN   AREA.  211 
Huronian.  Hudson  bay  as  a  whole  lies  in  the  great  Laurentian  area 
of  the  Dominion.  The  long  chain  of  islands  which  fringe  the  east  coast 
are  composed  of  bedded  volcanic  and  almost  unaltered  sedimentary 
rocks,  resembling  the  Nipigon  series  of  lake  Superior,  which  may  be  of 
Lower  Cambrian  age.  On  the  western  side  of  the  bay,  from  the  Churchill 
river  northward,  quartzites  and  other  rocks  are  found  which  may  also 
belong  to  the  Cambrian  system.  Cambro- Silurian  rocks  rest  almost 
horizontally  upon  the  Laurentian  along  the  southwestern  side  of  the  bay. 
Bell,6  in  1883,  reports  upon  the  geology  of  the  basin  of  Moose  river 
and  adjacent  country.  The  boundaries  of  the  Laurentian  and  Huro- 
nian formations  appear  to  be  conformable  to  each  other.  Massive 
granites  occur  abundantly  with  the  Laurentian  gneisses  and  Huronian 
schists.  The  granites  generally  lie  close  to  the  junction  of  the  Huro- 
nian and  Laurentian,  this  being  the  usual  position  of  these  granite 
areas  in  the  great  region  northward  of  lakes  Huron  and  Superior. 
Bell,7  in  1885,  describes  granite  and  gneiss  at  North  head,  Button 
islands,  Ungava  bay,  Nunaungok,  Ashe's  inlet,  Nottingham  and  Digges 
islands,  Stuparts  bay,  Eskimo  inlet,  port  DeBoucherville,  and  port 
Laperriere.  A  portion  of  the  west  coast  of  Hudson  bay  is  occupied 
with  diorites,  hornblende- schists  and  mica-schists,  which  may  be  re- 
ferred to  the  Huronian  series.  Deadman's  island  consists  of  white 
and  light-gray  quartzites,  and  glossy  mica-schists,  striking  north  75° 
west.  The  whole  of  the  western  part  of  Marble  island  consists  of  white 
and  light  colored  quartzite  bearing  a  strong  resemblance  to  white  and 
vein  marble.  The  beds  of  quartzite  are  very  massive,  although  their 
surfaces  are  often  ripple-marked,  being  sometimes  as  fine  and  regular 
as  the  fluting  on  a  washboard. 
B  ell,8  in  1885,  gives  a  general  characterization  of  the  geology  of 
Hudson  bay.  The  distribution  of  the  Huronian  series  is  intimately  con- 
nected with  that  of  the  Laurentian,  being  found  mostly  within  the 
limits  of  the  latter.  The  rocks  of  the  Huronian  system  appear  to  rest 
conformably  upon  the  Laurentian  in  all  cases  observed.  About  the 
mouth  of  Churchill  river,  on  the  west  side  of  the  bay,  and  for  some 
miles  along  the  coast,  are  found  massive  and  thinly  bedded  quartzites 
with  conglomerate  beds,  the  pebbles  being  mostly  of  white  quartz,  iu- 
terstratified  with  occasional  thin  shaly  layers.  These  strata  may  form 
a  part  of  the  Huronian  series,  but  they  also  resemble  the  gold-bearing 
rocks  of  Nova  Scotia.  On  the  Little  Whale  river  and  in  Richmond 
gulf  on  the  east  side  of  the  bay  another  set  of  rocks  is  found  following 
the  Huronian  and  underlying  unconformably  the  Nipigon  series.  This 
intermediate  formation  consists  of  beds  of  hard  red  siliceous  conglom- 
erate and  red  and  gray  sandstones,  with  some  red  shales,  and  appears 
to  have  a  considerable  volume.  The  Nipigon  formation  is  largely  de- 
veloped along  the  east  main  coast  of  Hudson  bay,  between  cape  Jones 
and  cape  Dufferin,  and  consists  of  compact,  nonfossiliferous,  bluish 
gray  limestones,  coarse  cherty  limestone  breccias,  quartzites,  shales, 
