﻿GEOLOGY 
  OF 
  THOUSAND 
  ISLANDS 
  REGION 
  

  

  i8s 
  

  

  Other 
  an 
  amphibolite 
  slightly 
  soaked 
  by 
  granite, 
  and 
  their 
  analyses 
  

   appear 
  herewith. 
  Each, 
  in 
  the 
  field, 
  was 
  classified 
  as 
  plainly 
  a 
  

   soaked 
  rock, 
  in 
  which 
  the 
  constituents 
  were 
  merged. 
  Each 
  was 
  

   also 
  merely 
  a 
  phase 
  in 
  a 
  gradual 
  increase 
  in 
  amount 
  of 
  soaking, 
  

   plainly 
  to 
  be 
  traced 
  in 
  the 
  field, 
  and 
  the 
  two 
  samples 
  were 
  chosen 
  

   from 
  among 
  many 
  because 
  of 
  unusual 
  freshness. 
  

  

  Si02... 
  

  

  AI2O3.. 
  

   Fe203.. 
  

   FeO... 
  

   MgO.. 
  

   CaO... 
  

   Na20.. 
  

   K2O... 
  

   H2O 
  + 
  . 
  

   H2O— 
  . 
  

   T1O2.. 
  

   Zr02. 
  . 
  

   P2O5.. 
  

  

  CI 
  

  

  F; 
  .... 
  

  

  S 
  

  

  MnO.. 
  

   BaO... 
  

  

  73 
  

   14 
  

  

  10 
  

   29 
  

   04 
  

   04 
  

  

  53 
  

   18 
  

   08 
  

   36 
  

   54 
  

   07 
  

   18 
  

  

  •03 
  

   •03 
  

   .02 
  

   ,02 
  

  

  .07 
  

  

  70.13 
  

  

  15-47 
  

   1.52 
  

   1.05 
  

  

  •85 
  

  

  1 
  .60 
  

  

  3-72 
  

  

  4-39 
  

  

  .48 
  

  

  .01 
  

  

  •30 
  

  

  •05 
  

   .09 
  

   .07 
  

   .08 
  

   •05 
  

  

  100.58 
  99.86 
  

  

  56.58 
  

  

  15-54 
  

  

  3.80 
  

  

  5-41 
  

  

  2-77 
  

  

  4-56 
  

  

  2 
  .91 
  

  

  4-25 
  

  

  .80 
  

  

  . 
  10 
  

  

  I. 
  71 
  

  

  .01 
  

  

  •87 
  

   . 
  12 
  

   .14 
  

   • 
  44 
  

   .09 
  

   .08 
  

  

  51-42 
  

   17.42 
  

   3-64 
  

   5-14 
  

   5 
  -11 
  

   6.76 
  

  

  3-74 
  

   3-33 
  

   •74 
  

   .09 
  

   1.25 
  

   .01 
  

   •71 
  

   •13 
  

   . 
  10 
  

  

  •23 
  

   .16 
  

  

  •13 
  

  

  50.83 
  

  

  18.64 
  

  

  2.84 
  

  

  5^97 
  

   4.90 
  

  

  7-5° 
  

   4. 
  22 
  

   1.83 
  

  

  1 
  .40 
  

  

  1 
  . 
  10 
  

  

  •03 
  

  

  .01 
  

  

  . 
  10 
  

  

  II 
  CO2 
  

  

  99-48 
  

  

  Note. 
  Cr203 
  and 
  CO2 
  absent. 
  

  

  1 
  ^ 
  Laurentian 
  granite 
  gneiss 
  of 
  Alexandria 
  bathylith, 
  from 
  column 
  4 
  of 
  

   original 
  table. 
  

  

  2 
  Laurentian 
  granite 
  gneiss 
  of 
  Antwerp 
  bathylith, 
  slightly 
  soaked 
  with 
  

   amphibolite, 
  column 
  5 
  of 
  original 
  table. 
  

  

  3 
  Amphibolite, 
  somewhat 
  soaked 
  by 
  granite, 
  from 
  railroad 
  cut 
  4 
  miles 
  

   north 
  of 
  Redwood 
  (8L2a, 
  Alexandria 
  sheet). 
  E. 
  W. 
  Morley, 
  analyst. 
  

  

  4 
  Amphibolite, 
  from 
  same 
  railroad 
  cut 
  (8L2B, 
  Alexandria 
  sheet). 
  

   E. 
  W. 
  Morley, 
  analyst. 
  

  

  5 
  Amphibolite 
  described 
  by 
  Adams 
  as 
  representing 
  the 
  extreme 
  stage 
  in 
  

   the 
  alteration 
  of 
  crystalline 
  limestone 
  into 
  amphibolite 
  by 
  contact 
  action 
  of 
  

   the 
  Glamorgan 
  bathylith, 
  Jour. 
  Geo. 
  17:2. 
  

  

  It 
  is 
  not 
  thought 
  that 
  the 
  amphibolite 
  of 
  analysis 
  4 
  is 
  an 
  altered 
  

   limestone, 
  but 
  rather 
  a 
  member 
  of 
  the 
  schist 
  series, 
  though 
  likely 
  a 
  

   calcareous 
  shale, 
  even 
  perhaps 
  an 
  impure 
  limestone. 
  In 
  any 
  case 
  

   its 
  similarity 
  in 
  composition 
  with 
  the 
  amphibolite 
  described 
  by 
  

   Adams 
  from 
  Maxwells 
  Crossing 
  is 
  quite 
  striking, 
  the 
  somewhat 
  

   higher 
  magnesia 
  and 
  potash 
  being 
  the 
  most 
  prominent 
  diflferences. 
  

  

  