NEW   ENGLAND.  589 
The  normal  succession  for  large  areas  in  western  New  England 
appears  to  be:  (1)  Pre-Cambrian  basement,  predominantly  of  igneous 
origin,  upon  which  unconformably  rest  (2)  quartzite  and  quartz 
schist,  (3)  limestone,  (1)  quartz-mica-feldspar  schist.  This  succes- 
sion is  but  rarely  completely  present.  Locally  each  member  of  the 
upper  series  is  found  to  rest  unconformably  upon  the  pre-Cambrian 
core.  This  distribution  would  be  in  accordance  with  the  view  that 
the  pre-Cambrian  shore  was  to  the  east,  and  thus  each  higher  member 
of  the  sedimentary  series  extended  by  overlap  beyond  the  lower 
formations  and  was  deposited  directly  on  the  pre-Cambrian  basement. 
Hobbs,93  in  1903  and  1904,  concludes  that  the  crystalline  rocks  of 
southwestern  New  England  have  been  deformed  by  a  system  of  joints 
and  faults  of  post-Newark  age  superimposed  upon  older  structures 
which  appear  to  be  largely  due  to  folding.  He  concludes  further 
that  the  crystalline  and  later  rocks  of  the  Atlantic  coast  in  general 
show  lineaments  suggesting  regular  sets  of  faults  in  a  nearly  merid- 
ional series  and  in  two  other  series  which  make  nearly  equal  angles 
with  this  direction.  Other  lineaments  which  more  closely  approach 
the  equatorial  direction  vary  more  from  one  another  and  are  both 
numerically  less  important  and  less  strikingly  brought  out. 
SECTION   8.     SUMMARY  OF    PRESENT    KNOWLEDGE    OF 
NEW  ENGLAND. 
The  following  summary  has  been  prepared  by  George  Otis  Smith: 
Tn  the  first  edition  of  this  bulletin  the  generalization  was  made 
that  large  areas  of  rocks  in  New  England  commonly  regarded  as  pre- 
Cambrian  were  proving  to  be  Cambrian  or  post-Cambrian  in  age. 
This  statement  is  well  substantiated  by  the  results  that  have  come 
with  the  progress  of  systematic  work  during  the  last  decade.  Not 
only  has  the  post-Algonkian  age  of  many  schists,  gneisses,  and  gran- 
ites been  proved,  but  the  line  between  the  pre-Cambrian  and  the 
younger  formations  has  been  accurately  determined  in  certain  areas 
and  to  some  extent  a  pre-Cambrian  succession  of  formations  has  been 
established. 
The  earlier  work  on  the  subject  of  the  origin  of  crystalline  schists 
and  their  correlation  with  known  clastic  formations  was  a  necessary 
preliminary  to  the  true  interpretation  of  New  England  geology. 
The  later  work  on  tin1  crystalline  rocks  of  this  province  has  resulted, 
first  of  all,  in  the  recognition  of  the  post-Algonkian  age  and  the 
clastic  nature  of  large  areas  of  metamorphic  schi-ts  and  gneisses,  hut 
there  has  also  been  a  great  advance  in  the  determination  of  (he  post- 
Algonkian  age  and  the  intrusive  character  of  many  masses,  small  and 
large,  of  granite  gneiss  and  granite  long  held  to  he  of  pre-Cambrian 
age.     The  adherence  of  New  England  geologists  to  the  theory  of  a 
