﻿GEOLOGx 
  OF 
  SARATOGA 
  SPRINGS 
  AND 
  VICINxfY 
  I39 
  

  

  The 
  Amsterdam 
  is 
  the 
  only 
  Black 
  River 
  . 
  formation 
  deposited 
  

   over 
  the 
  Saratoga 
  region. 
  The 
  margins 
  of 
  the 
  Lowville 
  and 
  Water- 
  

   town 
  troughs 
  did 
  not 
  quite 
  reach 
  the 
  district, 
  and 
  the 
  Amsterdam 
  

   rests 
  on 
  the 
  Little 
  Falls 
  dolomite. 
  It 
  is 
  the 
  oldest 
  Ordovicic 
  for- 
  

   mation 
  of 
  the 
  quadrangle. 
  Between 
  the 
  deposition 
  of 
  the 
  two 
  

   the 
  region 
  stood 
  as 
  a 
  land 
  area 
  on 
  the 
  margin 
  of 
  the 
  Champlain 
  

   trough. 
  The 
  small 
  amount 
  of 
  erosion 
  of 
  the 
  Little 
  Falls 
  sur- 
  

   face 
  during 
  this 
  long 
  interval 
  is 
  indicative 
  of 
  low 
  altitude 
  of 
  the 
  

   land. 
  

  

  The 
  pure 
  limestone 
  of 
  the 
  Amsterdam 
  denotes 
  also 
  low 
  alti- 
  

   tude 
  of 
  the 
  neighboring 
  land. 
  The 
  abundance 
  of 
  marine 
  fossils 
  

   shows 
  plentiful 
  life 
  in 
  the 
  waters. 
  

  

  Uplift 
  followed 
  Amsterdam 
  deposition, 
  the 
  Saratoga 
  region 
  pass- 
  

   ing 
  slightly 
  above 
  sea 
  level. 
  

  

  Succeeding 
  this 
  uplift 
  came 
  the 
  Trenton 
  submergence. 
  At 
  first, 
  

   beds 
  of 
  limestone 
  and 
  of 
  blackish 
  shale 
  alternated 
  with 
  one 
  an- 
  

   other; 
  but 
  the 
  limestone 
  soon 
  ceased 
  and 
  the 
  great 
  thickness 
  of 
  

   the 
  Canajoharie 
  shale 
  of 
  lower 
  Trenton 
  age 
  slowly 
  accumulated 
  

   in 
  the 
  subsiding 
  trough. 
  The 
  fossils 
  are 
  chiefly 
  graptolites 
  ; 
  open 
  

   sea 
  forms 
  swept 
  into 
  the 
  trough 
  by 
  marine 
  currents 
  which 
  ran 
  

   through 
  it. 
  Conditions 
  were 
  not 
  favorable 
  for 
  an 
  abundant 
  and 
  

   diversified 
  marine 
  fauna. 
  

  

  During 
  this 
  same 
  time 
  Trenton 
  limestones 
  were 
  being 
  deposited 
  

   on 
  the 
  west 
  side 
  of 
  the 
  Adirondacks, 
  in 
  clearer 
  seas 
  which 
  swarmed 
  

   with 
  marine 
  organisms. 
  Conditions 
  on 
  the 
  two 
  sides 
  of 
  the 
  region 
  

   were 
  thus 
  sharply 
  contrasted. 
  

  

  In 
  middle 
  Trenton 
  time 
  the 
  deeper 
  Canajoharie 
  sea 
  which 
  ex- 
  

   tended 
  from 
  the 
  Mohawk 
  valley 
  northward 
  through 
  the 
  Chazy- 
  

   Saratoga 
  basin 
  into 
  Canada 
  and 
  southward 
  through 
  the 
  Hudson 
  

   river 
  region 
  and 
  as 
  far 
  south 
  as 
  the 
  southern 
  Appalachians, 
  was 
  

   probably 
  drained 
  for 
  a 
  brief 
  period 
  in 
  this 
  region, 
  but 
  soon 
  again 
  

   the 
  shallow 
  sea 
  of 
  the 
  Schenectady 
  period 
  extended 
  through 
  the 
  

   trough 
  northward 
  to 
  an 
  unknown 
  extent, 
  but 
  undoubtedly 
  across 
  

   the 
  Saratoga 
  and 
  Schuylerville 
  quadrangles. 
  The 
  bottom 
  of 
  this 
  

   trough 
  kept 
  sinking 
  gradually, 
  so 
  that 
  upward 
  of 
  2000 
  feet 
  of 
  

   shallow 
  water 
  deposits 
  could 
  be 
  accumulated 
  in 
  it 
  in 
  Schoharie 
  and 
  

   Schenectady 
  counties. 
  

  

  In 
  the 
  following 
  Utica 
  period 
  this 
  region 
  was 
  probably 
  again 
  

   emerged, 
  for 
  no 
  Utica 
  deposits 
  have 
  as 
  yet 
  been 
  recognized 
  in 
  the 
  

   lower 
  Mohawk 
  and 
  Hudson 
  valleys, 
  the 
  so-called 
  Utica 
  beds 
  of 
  

   these 
  regions 
  all 
  being 
  now 
  known 
  to 
  be 
  of 
  Canajoharie 
  age. 
  It 
  

  

  