316  PRE-CAMBRIAN    GEOLOGY    OF    NORTH    AMERICA. 
At  these  contacts  the  lower  quartzite  of  the  Upper  series  contains 
abundant  fragments  of  the  Lower  series,  which  had  reached  their 
present  condition  before  being  deposited  in  the  former.  That  the 
Lower  series  had  been  greatly  folded  and  deeply  truncated  before 
the  Upper  series  was  deposited  is  further  shown  by  the  much  banded 
and  contorted  jasper  abutting  at  all  angles  against  the  beds  of  the 
uptilted  but  simply  folded  Upper  series,  and  also  by  its  more  crys- 
talline character. 
Since  great  belts  of  conglomerates  containing  abundant  fragments 
of  ore  and  jasper  are  found  in  the  Upper  Vermilion  at  Ogishki  Lake 
and  in  the  Upper  Kaministiquia  series,  it  is  argued  that  the  source 
of  this  material  are  the  great  belts  of  iron  ore  and  jasper  contained 
in  the  Lower  Vermilion,  Hunters  Island,  and  Lower  Kaministiquia 
series.  That  the  Vermilion  Lake  conglomerate  is  unconformably 
above  the  schists  in  vertical  attitude,  bearing  ore  and  jasper,  is  fur- 
ther indicated  by  the  fact,  discovered  by  Merriam,  that  on  the  islands 
of  Vermilion  Lake  the  conglomerate  is  found  to  be  in  a  series  of 
gentle  folds,  although  having  a  vertical  cleavage  developed.  Mer- 
riam regards  the  conglomerate  as  a  comparatively  thin  formation 
overlying  and  overlapping  the  Lower  series.  The  presence  of  red 
jasper  conglomerate  in  the  Original  Huronian  suggests  that  in  this 
district  will  be  found  a  Lower  series  similar  to  the  Lower  Vermilion 
bearing  jasper  and  ore. 
It  is  concluded  that  the  confusion  in  correlation  of  the  formations 
about  Lake  Superior  is  due  to  the  failure  to  recognize  this  general 
unconformity.  Once  recognized,  the  structural  conclusions  to  which 
the  various  writers  have  most  steadfastly  held  are  found  to  be  in 
general  harmony.  Above  the  physical  break,  and  constituting  the 
Upper  Huronian  (equivalent  to  the  Original  Huronian)  are  the 
Animikie  and  Upper  Kaministiquia,  Upper  Vermilion,  Upper  Mar- 
quette, western  Menominee,  Penokee-Gogebic  proper,  and  the  Dakota, 
Iowa,  Minnesota,  and  Wisconsin  quartzites,  surrounded  by  the  fos- 
siliferous  series.  In  the  Lower  Huronian  are  the  Keewatin  (in  part 
at  least) ,  Lower  Kaministiquia,  Lower  Vermilion,  Lower  Marquette, 
Felch  Mountain  iron-bearing  series,  Menominee  proper,  the  Cherty 
limestone  at  the  base  of  the  Penokee  series,  and  the  Black  River  Falls 
iron-bearing  schists. 
Lawson,327  in  1893,  on  lithological  grounds  suggests  the  following 
hypothetical  correlation  of  certain  rocks  of  western  Ontario  and 
Minnesota,  eastern  Ontario,  and  Quebec: 
