﻿60 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Southward 
  it 
  runs 
  into 
  shales 
  and 
  can 
  not 
  be 
  traced. 
  Northward 
  

   there 
  are 
  indications 
  of 
  it 
  for 
  a 
  mile, 
  beyond 
  which 
  it 
  is 
  hidden 
  by 
  

   drift. 
  

  

  McGregor 
  fault. 
  Darton 
  spoke 
  of 
  the 
  group 
  of 
  faults 
  about 
  

   Saratoga 
  as 
  the 
  Saratoga 
  faults. 
  The 
  group 
  seems 
  to 
  us 
  to 
  consist 
  

   of 
  a 
  main 
  fault 
  with 
  branches 
  and 
  we 
  desire 
  to 
  retain 
  the 
  name 
  

   Saratoga 
  fault 
  for 
  the 
  branch 
  in 
  the 
  village, 
  often 
  called 
  the 
  

   " 
  Springs 
  " 
  fault. 
  The 
  grand 
  scarp 
  of 
  the 
  main 
  fault 
  along 
  the 
  

   front 
  of 
  Mt 
  McGregor 
  has 
  suggested 
  that 
  as 
  a 
  most 
  fitting 
  name 
  

   for 
  this 
  fault. 
  

  

  In 
  front 
  of 
  Mt 
  McGregor 
  the 
  fault 
  has 
  Precambric 
  rocks 
  on 
  the 
  

   upthrow 
  side 
  and 
  Canajoharie 
  shale 
  on 
  the 
  downthrow, 
  so 
  that 
  

   the 
  full 
  thickness 
  of 
  the 
  Potsdam, 
  Theresa, 
  Hoyt, 
  Little 
  Falls 
  and 
  

   Amsterdam 
  formations 
  is 
  faulted 
  out. 
  This 
  means 
  a 
  minimum 
  

   thickness 
  of 
  at 
  least 
  600 
  feet 
  ; 
  in 
  addition 
  there 
  is 
  another 
  thickness 
  

   of 
  600 
  feet 
  of 
  Precambric 
  in 
  the 
  fault 
  scarp, 
  with 
  the 
  summit 
  likely 
  

   200 
  feet 
  below 
  the 
  horizon 
  of 
  the 
  base 
  of 
  the 
  Potsdam. 
  How 
  much 
  

   thickness 
  of 
  the 
  Canajoharie 
  shale 
  is 
  involved 
  is 
  uncertain, 
  but 
  the 
  

   throw 
  of 
  the 
  fault 
  is 
  certainly 
  1400 
  feet 
  at 
  Mt 
  McGregor, 
  and 
  likely 
  

   200 
  feet 
  more 
  than 
  that. 
  It 
  seems 
  to 
  be 
  increasing 
  toward 
  the 
  north. 
  

  

  Near 
  Kings 
  Station, 
  4 
  miles 
  north 
  of 
  Saratoga, 
  a 
  branch 
  fault 
  sets 
  

   off 
  from 
  the 
  main 
  fault 
  toward 
  the 
  northeast, 
  bringing 
  a 
  block 
  of 
  

   Little 
  Falls 
  dolomite 
  to 
  the 
  surface 
  between 
  the 
  shales 
  and 
  the 
  

   Precambric. 
  This 
  may 
  be 
  called 
  the 
  Gurnspring 
  fault. 
  Carbonated 
  

   waters 
  rise 
  along 
  it 
  in 
  the 
  same 
  way 
  and 
  under 
  very 
  similar 
  

   structural 
  conditions 
  as 
  they 
  do 
  along 
  the 
  Saratoga 
  fault. 
  This 
  

   block 
  of 
  dolomite 
  seems 
  cut 
  off 
  at 
  the 
  north 
  by 
  shales, 
  and 
  hence 
  by 
  

   another 
  fault, 
  but 
  rock 
  outcrops 
  are 
  so 
  few 
  that 
  conditions 
  are 
  very 
  

   conjectural. 
  

  

  To 
  the 
  northward 
  the 
  McGregor 
  fault 
  runs 
  as 
  one 
  of 
  the 
  prom- 
  

   inent 
  breaks 
  of 
  the 
  region, 
  passing 
  to 
  Lake 
  George 
  and 
  forming 
  the 
  

   prominent 
  fault 
  scarp 
  along 
  the 
  west 
  shore 
  of 
  the 
  lake 
  and 
  of 
  

   Northwest 
  bay, 
  at 
  the 
  apex 
  of 
  which 
  it 
  passes 
  inland 
  away 
  from 
  

   the 
  lake. 
  

  

  Between 
  Kings 
  Station 
  and 
  St 
  Clements 
  the 
  McGregor 
  fault 
  runs 
  

   unbroken, 
  but 
  at 
  the 
  latter 
  place, 
  somewhat 
  over 
  a 
  mile 
  north 
  of 
  

   Saratoga, 
  it 
  sends 
  off 
  two 
  branches, 
  much 
  diminishing 
  the 
  throw 
  of 
  

   the 
  main 
  fault. 
  This 
  swerves 
  around 
  to 
  the 
  west 
  and 
  becomes 
  

   eventually 
  lost 
  under 
  the 
  heavy 
  drift 
  of 
  the 
  Kayaderosseras 
  valley. 
  

   Its 
  throw 
  is 
  rapidly 
  diminishing 
  and 
  it 
  probably 
  dies 
  out 
  in 
  that 
  

   district. 
  

  

  