﻿108 
  C. 
  L. 
  Baker 
  — 
  Contributions 
  to 
  the 
  

  

  small' 
  amount 
  of 
  conglomerates 
  at 
  the 
  base; 
  the 
  Yeso 
  

   gypsum-bearing 
  red 
  beds 
  of 
  sands 
  and 
  clays 
  and 
  thin 
  

   gray 
  limestones 
  ; 
  and 
  the 
  San 
  Andreas 
  at 
  the 
  top, 
  mas- 
  

   sive 
  gray 
  limestone. 
  As 
  might 
  be 
  expected, 
  the 
  lower 
  

   two 
  formations 
  exhibit 
  in 
  the 
  region 
  herein 
  discussed 
  

   some 
  characteristics 
  different 
  from 
  those 
  of 
  Lee's 
  type 
  

   localities 
  farther 
  west,* 
  but 
  his 
  subdivisions 
  are 
  entirely 
  

   valid 
  throughout 
  eastern 
  New 
  Mexico. 
  

  

  Abo 
  Formation. 
  — 
  Everywhere 
  in 
  central 
  New 
  Mexico 
  

   where 
  the 
  contact 
  has 
  been 
  noted 
  between 
  the 
  Abo 
  and 
  

   Magdalena, 
  there 
  is 
  erosional 
  unconformity. 
  In 
  most 
  

   places 
  this 
  unconformity 
  is 
  an 
  angular 
  one 
  as 
  well. 
  Gen- 
  

   tle 
  folding 
  of 
  the 
  Magdalena 
  occurred 
  in 
  the 
  Sacramento 
  

   and 
  Sangre 
  de 
  Cristo 
  mountains, 
  accompanied 
  and 
  fol- 
  

   lowed 
  by 
  great 
  erosion 
  before 
  the 
  deposition 
  of 
  the 
  Abo. 
  

   Some 
  of 
  the 
  Abo 
  arkose 
  in 
  the 
  latter 
  range 
  may 
  have 
  

   been 
  derived 
  from 
  Magdalena 
  arkose 
  but 
  locally 
  in 
  that 
  

   range 
  Abo 
  rests 
  directly 
  upon 
  the 
  crystallines. 
  The 
  

   great 
  thickness 
  of 
  arkose 
  in 
  the 
  Abo 
  of 
  the 
  northern 
  Sac- 
  

   ramentos 
  was 
  probably 
  derived 
  from 
  exposed 
  crystalline 
  

   areas 
  farther 
  north 
  in 
  central 
  New 
  Mexico. 
  Abo 
  sedi- 
  

   ments 
  in 
  the 
  southern 
  part 
  of 
  the 
  San 
  Andreas 
  and 
  Sac- 
  

   ramento 
  mountains 
  were 
  deposited 
  in 
  somewhat 
  clearer 
  

   waters 
  than 
  those 
  farther 
  north. 
  

  

  The 
  Abo 
  outcrops 
  on 
  the 
  flanks 
  of 
  the 
  folds 
  of 
  the 
  

   southern 
  Sangre 
  de 
  Cristo 
  Mountains, 
  on 
  the 
  east 
  dip 
  

   slope 
  of 
  the 
  Sandia, 
  Manzano 
  and 
  Los 
  Pinos 
  ranges, 
  and 
  

   in 
  the 
  median 
  strike 
  valleys 
  of 
  the 
  Sacramento 
  and 
  San 
  

   Andreas 
  mountains. 
  It 
  probably 
  was 
  never 
  deposited 
  

   around 
  the 
  crystalline 
  masses 
  of 
  central 
  New 
  Mexico. 
  It 
  

   doubtless 
  underlies 
  from 
  one 
  third 
  to 
  one 
  half 
  of 
  the 
  

   entire 
  area 
  of 
  New 
  Mexico, 
  east 
  of 
  the 
  Rio 
  Grande. 
  

  

  The 
  Abo 
  formation 
  of 
  Glorieta 
  Mesa 
  in 
  the 
  vicinity 
  of 
  

   Eowe 
  and 
  Pecos 
  villages 
  has 
  an 
  estimated 
  thickness 
  of 
  

   about 
  800 
  feet, 
  including 
  the 
  lower 
  unconsolidated 
  brick- 
  

   red 
  uncemented 
  beds 
  which 
  are 
  very 
  poorly 
  exposed 
  in 
  

   the 
  strike 
  valley 
  east 
  of 
  the 
  mesa. 
  The 
  basal 
  beds, 
  one 
  

   and 
  one-fourth 
  miles 
  north 
  of 
  Fulton 
  station 
  on 
  the 
  

   Santa 
  Fe 
  main 
  line, 
  lie 
  unconformably 
  upon 
  the 
  Magda- 
  

   lena, 
  with 
  a 
  reworked 
  limestone 
  conglomerate 
  at 
  their 
  

   base, 
  and 
  immediately 
  above 
  the 
  base 
  a 
  massive 
  cross- 
  

   bedded 
  gray 
  arkosic 
  and 
  conglomeratic 
  sandstone 
  with 
  

   fragments 
  of 
  crystallines 
  and 
  Magdalena 
  limestone. 
  

   Just 
  east 
  of 
  Rowe 
  the 
  base 
  is 
  marked 
  by 
  a 
  thin 
  conglom- 
  

  

  