QUEBEC    NORTH    AND    WEST    OF    ST.    LAWRENCE    RIVER.  473 
rock.  Considerable  deformation  took  place  during  the  intrusion. 
Between  the  limestone  and  the  granite  is  a  highly  brecciated  zone, 
holding  large  amounts  of  lime-rich  silicates,  which  are  eminently 
characteristic  of  contact  metamorphism.  Diagenesis  took  place.  To 
a  great  extent,  however,  the  elements,  other  than  the  lime  necessary 
for  the  formation  of  these  minerals,  came  from  the  intrusion  and  its 
accompanying  exhalations.  The  metamorphism,  then,  was  largely 
also  nietasomatic.  In  the  gray  gneisses  and  in  the  granite  are  dark 
basic  masses,  which  represent  fragments  broken  off  from  the  lime- 
stone series  and  floated  away  into  the  igneous  mass.  They  have  been 
still  more  highly  metamorphosed  than  the  rocks  from  which  they 
came  and  have  been  more  or  less  dissolved  and  changed  in  character 
by  the  granite.  In  other  words,  they  have  been  partially  "  granitized." 
The  gray  gneisses,  which  have  the  composition  of  quartz  diorites, 
may  represent  an  intermediate  phase  of  this  "  granitization  "  be- 
tween the  inclusions  and  the  granite.  This  theory  may  account  for 
the  large  amount  of  plagioclase  feldspar  found  in  the  granite  itself. 
Haycock,52  in  1905,  discusses  the  geology  of  part  of  the  county  of 
Ottawa  along  Lievre  River.  This  is  a  typical  Laurentian  area  of 
granites,  gneisses,  and  schists,  including  bands  of  limestone,  quartzites, 
and  gneisses  of  sedimentary  origin.  It  is  concluded  that  unevenness 
in  original  deposition  appears  the  most  natural  way  to  account  for 
the  erratic  distribution  of  the  limestone.  In  one  area  evidence  is  in 
accord  with  the  hypothesis  of  the  unconformable  superposition  and 
subsequent  infolding  of  the  limestone  with  a  gneiss  and  quartzite.  the 
whole  then  being  disturbed  by  the  acidic  intrusives.  At  another  place 
the  limestones  seem  to  be  interstratified  with  the  gneisses  and  quartz- 
ites, The  relations  of  the  sedimentary  rocks  to  the  massive  gneisses 
are  unknown.  The  gneisses  are  regarded  as  of  igneous  origin,  but 
whether  older  or  newer  than  the  surrounding  rocks,  or  of  contem- 
poraneous origin,  was  not  determined. 
Johnston  (J.  F.  E.),53  in  1905,  reports  on  the  geology  of  part  of 
the  county  of  Ottawa  along  Lievre  River,  a  part  of  the  Original 
Laurentian  area. 
Ells,54  in  1905,  discusses  the  geology  of  a  portion  of  eastern  On- 
tario in  the  counties  of  Renfrew,  Addington,  Frontenac,  Lanark. 
and  Carleton.  The  rocks  in  this  area  may  be  roughly  divided  into 
several  groups,  as  follows: 
1.  Granite  gneiss  and  syenite,  which  apparently  represent  the 
oldest  series,  upon  which  the  others  rest. 
2.  Gneiss,  often  grayish  or  reddish  gray,  sometimes  highly  quartz- 
ose  and  garnetiferous,  but  of  various  shades  of  color,  certain  por- 
tions of  which  pass  upward  into  limestones.    Hastings  series. 
3.  Amphibolites  with  schists,  sometimes  micaceous,  sparkling  and 
glistening,  often  containing  garnets;  at  other  times  chloritic,  horn- 
