﻿GEOLOGY 
  OF 
  SARATOGA 
  SPRINGS 
  AND 
  VICINITY 
  137 
  

  

  extended 
  southward 
  up 
  the 
  Champlain 
  trough, 
  and 
  westward 
  up 
  

   the 
  St 
  Lawrence 
  trough. 
  

  

  The 
  currents 
  which 
  transported 
  these 
  coarse 
  sands 
  and 
  gravels 
  

   must 
  have 
  been 
  vigorous 
  ones, 
  suggesting 
  rather 
  strong 
  relief 
  of 
  

   the 
  land 
  which 
  lay 
  to 
  the 
  south 
  and 
  west. 
  All 
  fine 
  material 
  was 
  

   washed 
  and 
  blown 
  to 
  a 
  distance. 
  

  

  The 
  sands 
  of 
  the 
  Potsdam 
  are 
  succeeded 
  by 
  the 
  alternating 
  sands 
  

   and 
  dolomites 
  of 
  the 
  Theresa 
  formation 
  without 
  any 
  sign 
  of 
  a 
  

   break 
  between 
  them. 
  Erosion 
  had 
  lowered 
  the 
  bordering 
  lands. 
  

   Sand 
  came 
  down 
  only 
  intermittently 
  and 
  in 
  less 
  volume, 
  and 
  beds 
  

   of 
  dolomite 
  began 
  to 
  be 
  deposited. 
  The 
  sands 
  steadily 
  diminish 
  

   in 
  frequency 
  and 
  thickness, 
  and 
  thus 
  the 
  Theresa 
  formation 
  grades 
  

   upward 
  into 
  the 
  Little 
  Falls 
  dolomite. 
  Both 
  these 
  formations 
  are 
  

   marine, 
  but 
  in 
  both 
  of 
  them 
  fossils 
  are 
  very 
  rare, 
  especially 
  in 
  

   the 
  dolomite. 
  The 
  great 
  reefs 
  of 
  Cryptozoon, 
  which 
  occur 
  at 
  

   many 
  horizons, 
  seem 
  to 
  indicate 
  the 
  likelihood 
  of 
  abundant 
  life 
  and 
  

   to 
  suggest 
  that 
  the 
  scarcity 
  of 
  fossils 
  is 
  more 
  likely 
  due 
  to 
  un- 
  

   favorable 
  conditions 
  for 
  preservation 
  than 
  to 
  their 
  absence 
  in 
  the 
  

   marine 
  waters. 
  

  

  The 
  Hoyt 
  limestone 
  is 
  a 
  local 
  upper 
  phase 
  of 
  the 
  Theresa 
  for- 
  

   mation 
  about 
  Saratoga. 
  It 
  seems 
  to 
  represent 
  a 
  more 
  offshore 
  

   phase 
  of 
  the 
  formation, 
  and 
  fossils 
  are 
  much 
  more 
  abundant 
  than 
  

   in 
  the 
  ordinary 
  Theresa 
  or 
  the 
  Little 
  Falls 
  dolomite. 
  This 
  may 
  

   in 
  part 
  be 
  due 
  to 
  the 
  offshore 
  character 
  of 
  the 
  Hoyt, 
  but 
  it 
  also 
  

   suggests 
  more 
  favorable 
  conditions 
  of 
  preservation. 
  

  

  These 
  three 
  formations 
  are 
  of 
  extreme 
  upper 
  Cambric 
  age 
  (U1-. 
  

   rich 
  would 
  class 
  them 
  as 
  Ozarkic), 
  and 
  are 
  the 
  only 
  Cambric 
  de- 
  

   posits 
  that 
  were 
  laid 
  down 
  along 
  the 
  Champlain 
  trough. 
  Following 
  

   their 
  deposit 
  mild 
  uplift 
  occurred 
  and 
  the 
  troughs 
  came 
  above 
  sea 
  

   level, 
  existed 
  as 
  land 
  for 
  a 
  space, 
  and 
  were 
  somewhat 
  eroded. 
  This 
  

   erosion 
  gently 
  bevelled 
  off 
  the 
  surface 
  instead 
  of 
  deeply 
  cutting 
  

   into 
  it, 
  which 
  suggests 
  that 
  the 
  land 
  was 
  of 
  low 
  altitude. 
  

  

  ORDOVICIC 
  HISTORY 
  

  

  The 
  uplift 
  just 
  mentioned 
  forms 
  for 
  the 
  geologist 
  the 
  dividing 
  

   plane 
  between 
  the 
  New 
  York 
  Cambric 
  formations 
  and 
  those 
  classed 
  

   as 
  of 
  Ordovicic 
  age. 
  No 
  one 
  has 
  any 
  clear 
  idea 
  in 
  regard 
  to 
  the 
  

   length 
  of 
  elapsed 
  time 
  which 
  this 
  uplift 
  represents. 
  Eventually 
  

   the 
  troughs 
  became 
  again 
  depressed 
  and 
  occupied 
  by 
  marine 
  waters 
  ; 
  

   and 
  in 
  these, 
  on 
  all 
  four 
  sides 
  of 
  the 
  Adirondack 
  region, 
  the 
  various 
  

  

  