﻿H. 
  A. 
  Daly 
  — 
  Geology 
  of 
  Pigeon 
  Point, 
  Minnesota. 
  425 
  

  

  miles 
  (10 
  kilometers) 
  long 
  ; 
  its 
  maximum 
  width 
  is 
  a 
  little 
  more 
  

   than 
  one 
  mile. 
  Its 
  area 
  is 
  small 
  ; 
  yet, 
  on 
  account 
  of 
  a 
  dense 
  

   growth 
  of 
  moss 
  and 
  trees 
  over 
  much 
  of 
  the 
  interior, 
  a 
  correct 
  

   delineation 
  of 
  all 
  significant 
  contacts 
  of 
  the 
  rocks 
  must 
  take 
  

   much 
  time. 
  The 
  scant 
  six 
  days 
  spent 
  on 
  the 
  point 
  did 
  not 
  suf- 
  

   fice 
  for 
  a 
  complete 
  field 
  review 
  of 
  the 
  geology, 
  but 
  it 
  was 
  

   possible, 
  with 
  the 
  liberal 
  and 
  highly 
  expert 
  help 
  of 
  Professor 
  

   Palache, 
  to 
  trace 
  most 
  of 
  the 
  contacts 
  in 
  the 
  eastern 
  third 
  of 
  

   the 
  peninsula, 
  an 
  area 
  of 
  about 
  2 
  square 
  kilometers 
  ; 
  and 
  to 
  run 
  

  

  Fig. 
  1. 
  

  

  PIGEON 
  

  

  BAY 
  

  

  B 
  

  

  1'.':. 
  "'•!*"'."•.• 
  .'•■ 
  1 
  ;\ 
  ••.'*'."•."' 
  • 
  

  

  

  

  >'•:•' 
  •- 
  1 
  -* 
  •"'-•: 
  

  

  . 
  2 
  . 
  " 
  3, 
  _J 
  

  

  

  A 
  

  

  

  ^^B^y^Q 
  

  

  

  ■w^-'---— 
  ^ 
  

  

  LAKE 
  

  

  5 
  U 
  P 
  E 
  R 
  1 
  O 
  R 
  

  

  ' 
  

  

  

  o 
  

  

  'A 
  V.2. 
  

  

  3 
  /f4 
  mile: 
  

  

  o 
  

  

  i 
  

  

  K 
  M. 
  

  

  

  

  Fig. 
  1. 
  The 
  eastern 
  part 
  of 
  Pigeon 
  Point. 
  Aniniikie 
  sediments, 
  left 
  

   blank 
  ; 
  1, 
  gabbro 
  ; 
  2, 
  intermediate 
  rock 
  ; 
  3, 
  red 
  rock. 
  Diabase 
  and 
  gabbro 
  

   dikes 
  in 
  solid 
  black. 
  Sediments 
  and 
  sill 
  (1 
  — 
  3) 
  dip 
  about 
  15° 
  in 
  a 
  direotion 
  

   somewhat 
  east 
  of 
  south. 
  

  

  a 
  few 
  cross-sections 
  in 
  the 
  broader 
  part 
  of 
  the 
  peninsula, 
  to 
  the 
  

   westward. 
  

  

  In 
  general, 
  the 
  maps 
  of 
  the 
  western 
  two-thirds 
  of 
  the 
  penin- 
  

   sula, 
  shown 
  in 
  Bayley's 
  Plates 
  XIV 
  and 
  XY, 
  were 
  found 
  not 
  

   to 
  need 
  any 
  essential 
  change. 
  The 
  eastern 
  third 
  is 
  likewise 
  

   accurately 
  mapped 
  by 
  Bayley 
  so 
  far 
  as 
  the 
  shore 
  zones 
  are 
  con- 
  

   cerned. 
  Close 
  study 
  of 
  the 
  less 
  well-exposed 
  interior 
  showed, 
  

   however, 
  the 
  necessity 
  of 
  significant 
  changes 
  in 
  the 
  mapping 
  

   of 
  contacts, 
  though 
  no 
  vital 
  improvement 
  can 
  be 
  offered 
  on 
  his 
  

   remarkably 
  thorough 
  diagnosis 
  of 
  the 
  kind 
  of 
  rocks 
  occurring 
  

   in 
  the 
  area. 
  

  

  The 
  most 
  important 
  alterations 
  of 
  the 
  geological 
  map 
  are 
  

   noted 
  in 
  the 
  isthmus 
  at 
  Little 
  Portage 
  Bay 
  (" 
  E" 
  in 
  fig. 
  l)and 
  

  

  