vanhise.]  LAKE    SUPERIOR    REGION.  127 
are  interstratified  eruptives  and  sedimentaries,  as  is  the  Cuprifer- 
ous series.  On  Kekekabik  lake  there  is  an  extension  of  the  Ogishki 
Manissi  conglomerate  westward.  The  green  schist  conglomerates  here 
found  are  apparently  of  about  the  same  date  as  the  Ogishki  conglom- 
erate or  else  its  immediate  conformable  successor.  The  Animikie 
slates  associated  with  this  green  schist  conglomerate  are  also  in  con- 
formable succession  to  the  green  schists,  but  it  is  likely  that  this  con- 
formity would  not  be  found  in  the  vicinity  of  the  old  volcanic  vents. 
Winchell  (Alex.),175  in  1888,  finds  upon  Wonder  island  in  Saganaga 
lake  a  conglomerate  which  contains  abundant  rounded  pebbles  in  a 
groundmass  of  syenite.  The  lower  limit  of  the  conglomerate  is  quite 
abrupt,  and  whether  it  overlies  the  syenite  or  grades  into  it  is  uncer- 
tain, but  it  is  figured  as  overlying  the  syenite.  The  syenite  is  regarded 
as  erupted  after  the  conglomerate  existed  and  the  conglomerate  was 
not  laid  down  on  the  solidified  syenite.  The  Animikie  slates  are  found 
resting  unconformably  upon  vertical  schists,  gneisses,  and  syenites  at 
several  points  on  Gunflint  lake,  2  miles  west  of  Gunflint  hike,  and  on 
the  north  side  of  Epsilon  lake.  On  the  west  side  of  Sea  Gull  lake  the 
conglomerate  and  syenite  are  interbedded.  This  conglomerate  is 
thought  to  be  comparable  with  that  of  Wonder  island.  On  the  north 
side  of  the  same  lake  the  syenite  contains  sharply  limited  rounded  peb- 
bles and  irregular  masses  of  hornblendic  and  diabasic  material.  On 
Epsilon  lake  the  argillite  has  schistic  planes  standing  vertical,  while 
the  bedded  structure  has  a  dip  of  only  23°. 
Summing  up  the  succession:  At  the  base  are  the  granitoid  and 
gneissoid  rocks  in  three  areas,  the  Basswood,  White  Iron,  and  Saganaga 
lakes.  These  granitic  masses  everywhere  have  a  bedded  structure 
more  or  less  distinct.  They  are  traversed  by  quartzose  and  granu- 
litic  veins,  as  well  as  dikes  of  diabase.  The  gneisses  and  granites 
are  flanked  by  vertical  crystalline  schists  of  the  Vermilion  group.  The 
transition  from  the  gneisses  to  the  crystalline  schists  is  never  abrupt,  but 
is  a  structural  gradation,  near  the  line  of  junction  the  beds  of  gneisses 
and  schists  occurring  in  many  alternations.  Above  the  Vermilion  group 
are  the  Keewatin  semicrystalline  schists,  the  two  series  being  every- 
where conformable;  but  there  is  a  somewhat  abrupt  change  from  one 
group  to  the  other,  and  there  is  a  possibility  that  the  original  uncon- 
formity has  been  destroyed  by  lateral  pressure,  although  such  an  un- 
conformity^tethought  improbable.  There  has  been  no  actual  connection 
traced  betwe%i  the  Keewatin  schists  north  of  Gunflint  lake  and  those 
of  Knife  lake.  The  Keewatin  schists  are  almost  everywhere  veil  ically 
bedded.  When  the  bedding  is  obscure  this  is  sometimes  due  to  the 
action  of  erupted  masses,  but  more  often  the  cause  of  the  metamor- 
phosed condition  of  the  strata  is  not  ascribable  to  any  visible  euuse. 
The  Keewatin  schists  include  graywacke,  argillite,  sericite- schist,  chlo- 
rite schist,  porphyrellyte  schist  and  hematite. 
The  Ogishki  conglomerate  is  placed  as  a  part  of  the  Keewatin  system 
