﻿JAN 
  ^ 
  

  

  

  AMERICAN 
  JOURNAL 
  OF 
  SCIENCE 
  

  

  [FO 
  URTH 
  SERIES.] 
  

  

  Art. 
  I. 
  — 
  Paleo 
  geography 
  and 
  Diastrophism 
  in 
  the 
  

   Atlantic- 
  Arctic 
  Region 
  during 
  Paleozoic 
  Time; 
  by 
  

   Olaf 
  Holtedahl. 
  

  

  With 
  their 
  vast 
  continent, 
  where 
  richly 
  fossiliferous 
  

   Paleozoic 
  sediments 
  occnr 
  and 
  may 
  be 
  studied 
  through- 
  

   out 
  wide 
  areas, 
  North 
  American 
  stratigraphers 
  naturally 
  

   became 
  leaders 
  in 
  Paleozoic 
  paleogeography. 
  Europe, 
  

   split 
  up 
  into 
  a 
  large 
  number 
  of 
  nationalities, 
  speaking 
  

   many 
  different 
  languages, 
  with 
  the 
  strata 
  of 
  the 
  older 
  

   systems 
  much 
  more 
  tectonically 
  disturbed 
  and 
  metamor- 
  

   phosed 
  over 
  considerably 
  greater 
  areas, 
  offers 
  far 
  less 
  

   attractive 
  conditions 
  for 
  unravelling 
  the 
  geographies 
  of 
  

   Paleozoic 
  time. 
  

  

  While 
  a 
  great 
  many 
  paleogeographic 
  maps 
  illustrating 
  

   the 
  conditions 
  of 
  Mesozoic, 
  and 
  especially 
  Cenozoic, 
  time 
  

   have 
  been 
  published, 
  those 
  treating 
  of 
  the 
  Paleozoic 
  of 
  

   Europe 
  have 
  been 
  very 
  few. 
  We 
  have 
  the 
  well 
  known, 
  

   world-embracing 
  maps 
  of 
  Freeh, 
  Lapparent, 
  Haug, 
  and 
  

   in 
  quite 
  recent 
  times 
  those 
  of 
  Arldt, 
  wherein 
  a 
  summary 
  

   of 
  older 
  views 
  is 
  given, 
  but 
  these 
  maps 
  embrace 
  far 
  too 
  

   long 
  a 
  time, 
  especially 
  for 
  the 
  Ordovician 
  and 
  Silurian 
  

   periods, 
  since 
  but 
  one 
  map 
  is 
  given 
  for 
  the 
  whole 
  of 
  each 
  

   period. 
  On 
  the 
  other 
  hand, 
  some 
  districts 
  of 
  northern 
  

   Europe 
  have 
  been 
  treated 
  in 
  a 
  number 
  of 
  special 
  maps, 
  

   as 
  those 
  of 
  the 
  British 
  Isles 
  by 
  Jukes-Browne, 
  and 
  those 
  

   of 
  Eussia 
  by 
  Karpinsky 
  ; 
  the 
  suggestions 
  made 
  by 
  these 
  

   authors 
  have 
  to 
  a 
  considerable 
  extent 
  been 
  followed 
  in 
  

   some 
  of 
  the 
  maps 
  here 
  presented. 
  For 
  the 
  North 
  

   American 
  continent 
  the 
  maps 
  of 
  Schuchert 
  (1910 
  and 
  

   1915) 
  have 
  been 
  used. 
  Other 
  American 
  authors, 
  as 
  

   Weller, 
  Bassler, 
  and 
  Grabau, 
  have 
  presented 
  maps 
  em- 
  

  

  Am. 
  Jour. 
  Sci.— 
  Fourth 
  Series, 
  Vol. 
  XLIX, 
  No. 
  289.— 
  January, 
  1920. 
  

  

  