﻿Richardson 
  — 
  Paleozoic 
  Section 
  in 
  Northern 
  Utah. 
  -115 
  

  

  are 
  poor, 
  the 
  Wells 
  appears 
  to 
  be 
  less 
  than 
  300 
  feet 
  thick, 
  

   while 
  in 
  the 
  latter 
  area 
  this 
  formation 
  measures 
  600 
  feet. 
  

   Approximately 
  the 
  lower 
  third 
  of 
  the 
  formation 
  is 
  composed 
  

   of 
  alternating 
  layers 
  of 
  thin-beddecl 
  quartzite 
  and 
  limestone, 
  

   the 
  middle 
  third 
  of 
  massive 
  quartzite, 
  and 
  the 
  remaining 
  

   upper 
  part 
  of 
  the 
  formation 
  consists 
  of 
  calcareous 
  sandstone 
  

   and 
  sandy 
  limestone. 
  An 
  unconformity 
  at 
  the 
  base 
  of 
  the 
  

   Wells 
  formation 
  is 
  indicated 
  by 
  the 
  varying 
  thickness 
  of 
  the 
  

   underlying 
  Brazer 
  limestone, 
  by 
  the 
  apparent 
  absence 
  in 
  

   the 
  Randolph 
  quadrangle 
  of 
  a 
  richly 
  fossiliferous 
  horizon 
  near 
  

   the 
  top 
  of 
  the 
  Brazer 
  limestone, 
  present 
  in 
  the 
  Montpelier 
  

   quadrangle, 
  and 
  by 
  the 
  absence 
  of 
  the 
  red 
  sandstone, 
  Mor- 
  

   gan 
  formation, 
  Avhich 
  occurs 
  at 
  the 
  base 
  of 
  the 
  Pennsylvanian 
  

   section 
  in 
  Weber 
  Canyon. 
  It 
  should 
  be 
  noted 
  that 
  the 
  thick- 
  

   ness 
  of 
  rocks 
  of 
  Pennsylvanian 
  age 
  varies 
  greatly 
  in 
  this 
  

   general 
  region. 
  In 
  Weber 
  Canyon, 
  Utah, 
  although 
  exact 
  

   measurements 
  have 
  not 
  been 
  made, 
  there 
  are 
  several 
  thousand 
  

   feet 
  of 
  beds 
  of 
  that 
  age. 
  This 
  great 
  mass 
  of 
  rocks 
  is 
  reported 
  

   by 
  Blackwelder 
  * 
  to 
  have 
  disappeared 
  about 
  seven 
  miles 
  north 
  

   of 
  Weber 
  River. 
  As 
  stated 
  above, 
  in 
  the 
  Randolph 
  quadrangle 
  

   the 
  rocks 
  of 
  Pennsylvanian 
  age 
  range 
  from 
  less 
  than 
  300 
  to 
  

   about 
  600 
  feet 
  in 
  thickness, 
  and 
  in 
  southern 
  Idaho, 
  Richards 
  

   and 
  Mansfield 
  report 
  the 
  Wells 
  formation 
  to 
  be 
  2400 
  feet 
  

   thick. 
  

  

  Phosphoria 
  Formation. 
  

  

  The 
  Phosphoria 
  formation, 
  named 
  by 
  Richards 
  and 
  Mans- 
  

   tieldf 
  from 
  Phosphoria 
  Gulch, 
  a 
  branch 
  of 
  Georgetown 
  Can- 
  

   yon, 
  Bear 
  Lake. 
  County, 
  Idaho, 
  includes 
  the 
  phosphate 
  deposits 
  

   and 
  associated 
  beds 
  of 
  Permian 
  ? 
  age 
  which 
  lie 
  between 
  the 
  

   Pennsylvanian 
  Wells 
  formation 
  and 
  the 
  Woodside 
  shale 
  of 
  

   Triassic 
  age. 
  In 
  northern 
  Utah 
  (Randolph 
  quadrangle) 
  the 
  

   Phosphoria 
  formation 
  is 
  about 
  400 
  feet 
  thick. 
  The 
  upper 
  part 
  

   of 
  the 
  formation 
  consists 
  of 
  chert, 
  chert 
  j 
  limestone, 
  and 
  some 
  

   intercalated 
  shales 
  from 
  125 
  to 
  200 
  feet 
  thick, 
  and 
  the 
  lower 
  

   part 
  is 
  composed 
  of 
  a 
  sequence 
  about 
  200 
  feet 
  thick 
  of 
  brown 
  

   and 
  gray 
  clay 
  shale, 
  subordinate 
  limestone, 
  and 
  layers 
  up 
  to 
  

   5 
  feet 
  thick 
  of 
  oolitic 
  phosphate 
  rock. 
  

  

  At 
  several 
  widely 
  separated 
  localities 
  (noted 
  by 
  Blackwel- 
  

   der 
  J 
  north 
  of 
  Weber 
  Canyon, 
  by 
  Richards 
  and 
  Mansfield, 
  § 
  in 
  

   Idaho, 
  and 
  exposed 
  in 
  the 
  Randolph 
  quadrangle, 
  a 
  mile 
  north 
  

   of 
  Brazer 
  Canyon), 
  a 
  zone 
  of 
  breccia-conglomerate 
  is 
  present 
  

   at 
  or 
  near 
  the 
  base 
  of 
  the 
  Phosphoria 
  formation. 
  This 
  is 
  

  

  * 
  Bulletin, 
  Geological 
  Society 
  of 
  America, 
  vol. 
  xxi, 
  p. 
  531, 
  1910. 
  

   f 
  Richards 
  and 
  Mansfield 
  : 
  The 
  Banaock 
  Overthrust, 
  Journal 
  of 
  Geology, 
  

   vol. 
  xx, 
  pp. 
  684-689, 
  1912. 
  

  

  % 
  Bulletin, 
  Geological 
  Society 
  of 
  America, 
  vol. 
  xxi, 
  pp. 
  530-533, 
  1910. 
  

   § 
  Journal 
  of 
  Geology, 
  vol. 
  xx, 
  p. 
  692, 
  1912. 
  

  

  