﻿GEOLOGY 
  OF 
  SARATOGA 
  SPRINGS 
  AND 
  VICINITY 
  49 
  

  

  for 
  the 
  most 
  part. 
  Its 
  uniform, 
  carbonaceous, 
  fine 
  grained 
  char- 
  

   acter 
  is 
  the 
  most 
  distinguishing 
  feature 
  of 
  the 
  formation. 
  

  

  Much 
  of 
  the 
  shale 
  contains 
  pyrite 
  which, 
  becoming 
  oxydized, 
  fills 
  

   the 
  cleavage 
  and 
  bedding 
  planes 
  in 
  some 
  places 
  with 
  rusty 
  brown 
  

   films 
  and 
  produces 
  efflorescences 
  of 
  alum 
  salts 
  on 
  the 
  protected 
  walls 
  

   of 
  cliffs, 
  as 
  about 
  Ballston 
  Spa, 
  and 
  is 
  probably 
  also 
  responsible 
  for 
  

   the 
  occurrence 
  of 
  sulphuretted 
  hydrogen 
  in 
  some 
  of 
  the 
  springs. 
  

   In 
  some 
  cases 
  the 
  graptolites 
  were 
  found 
  very 
  well 
  preserved 
  in 
  

   pyrite. 
  

  

  These 
  shales 
  are 
  flat 
  on 
  the 
  two 
  quadrangles 
  here 
  described, 
  and 
  

   are 
  not 
  involved 
  in 
  the 
  intensive 
  folding 
  and 
  overthrusting 
  that 
  has 
  

   affected 
  the 
  Georgian, 
  Normanskill 
  and 
  Snake 
  Hill 
  beds, 
  although 
  

   they 
  may 
  dip 
  steeply 
  near 
  the 
  fault 
  planes. 
  Owing 
  to 
  their 
  uniform 
  

   softness 
  and 
  flat 
  position, 
  they 
  have 
  not 
  only 
  been 
  very 
  deeply 
  

   eroded 
  but 
  also 
  fail 
  to 
  form 
  ridges 
  of 
  folded 
  harder 
  beds, 
  as 
  the 
  

   other 
  shale 
  formations 
  of 
  the 
  region 
  do. 
  Outcrops 
  are 
  therefore 
  

   extremely 
  scarce 
  in 
  the 
  entire 
  belt, 
  occurring 
  only 
  where 
  the 
  creeks 
  

   have 
  accidentally 
  reached 
  a 
  higher 
  part 
  of 
  the 
  shale 
  surface, 
  that 
  

   for 
  the 
  most 
  part 
  is 
  deeply 
  buried 
  under 
  drift. 
  Since 
  practically 
  

   every 
  outcrop 
  of 
  this 
  shale 
  is 
  fossiliferous, 
  most 
  outcrops 
  are 
  marked 
  

   on 
  the 
  map 
  as 
  fossil 
  localities. 
  

  

  On 
  the 
  Saratoga 
  quadrangle 
  the 
  most 
  important 
  outcrops 
  are 
  

   about 
  Ballston 
  Spa 
  where 
  the 
  Kayaderosseras 
  flows 
  between 
  cliffs 
  

   of 
  this 
  shale 
  100 
  feet 
  high. 
  A 
  few 
  small 
  outcrops 
  sufficient 
  to 
  

   demonstrate 
  the 
  areal 
  extent 
  of 
  the 
  formation 
  were 
  observed 
  in 
  

   the 
  bed 
  of 
  the 
  Glowegee 
  and 
  its 
  branches, 
  in 
  the 
  southwest 
  corner 
  

   of 
  the 
  Saratoga 
  map, 
  and 
  another 
  in 
  the 
  creek 
  bed 
  at 
  the 
  Geyser 
  

   and 
  Carlsbad 
  springs 
  2 
  miles 
  southwest 
  of 
  Saratoga 
  Springs. 
  Thence 
  

   northeastward 
  all 
  rock 
  is 
  hopelessly 
  buried 
  under 
  sand 
  until 
  the 
  

   Snook 
  kill 
  is 
  reached, 
  which 
  in 
  its 
  upper 
  branches 
  exposes 
  shale 
  

   cliffs 
  at 
  the 
  foot 
  of 
  Mt 
  McGregor 
  and 
  falls 
  and 
  flows 
  over 
  Cana- 
  

   joharie 
  rock 
  for 
  several 
  miles 
  north 
  of 
  Gansevoort. 
  It 
  again 
  reaches 
  

   bedrock 
  about 
  4 
  miles 
  above 
  the 
  mouth 
  of 
  the 
  creek. 
  

  

  The 
  thickness 
  of 
  this 
  formation 
  could 
  not 
  be 
  determined 
  in 
  the 
  

   area 
  here 
  mapped 
  from 
  the 
  facts 
  at 
  hand. 
  We 
  know, 
  however, 
  that 
  

   not 
  more 
  than 
  15 
  miles 
  to 
  the 
  southwest 
  it 
  is 
  not 
  less 
  than 
  1100 
  feet 
  

   and 
  there 
  is 
  no 
  reason 
  why 
  it 
  should 
  originally 
  have 
  greatly 
  di- 
  

   minished 
  toward 
  Saratoga 
  county, 
  this 
  direction 
  lying 
  in 
  line 
  with 
  

   the 
  probable 
  axis 
  of 
  the 
  trough 
  in 
  which 
  deposition 
  took 
  place. 
  

   Since, 
  however, 
  the 
  shale 
  in 
  this 
  region 
  was 
  earlier 
  uncovered 
  by 
  

   erosion 
  than 
  the 
  belt 
  at 
  the 
  foot 
  of 
  the 
  Helderberg 
  escarpment, 
  it 
  

  

  