﻿Stratigraphy 
  of 
  Eastern 
  Netv 
  Mexico. 
  117 
  

  

  Mountain 
  formation, 
  and 
  the 
  strata 
  from 
  266 
  to 
  2455 
  feet 
  

   are 
  regarded 
  as 
  the 
  equivalent 
  of 
  the 
  Capitan 
  limestone. 
  

   Logs 
  of 
  artesian 
  wells 
  in 
  the 
  Pecos 
  Valley 
  between 
  

   Lake 
  McMillan 
  and 
  Roswell 
  show 
  red 
  beds, 
  salt 
  and 
  gyp- 
  

   sum 
  above 
  the 
  San 
  Andreas 
  limestone. 
  The 
  deeper 
  bor- 
  

   ings 
  in 
  the 
  vicinity 
  of 
  Roswell 
  penetrate 
  both 
  the 
  upper 
  

   red 
  beds 
  and 
  the 
  lower 
  Manzano 
  red 
  beds, 
  the 
  two 
  series 
  

   being 
  separated 
  by 
  the 
  intervening 
  San 
  Andreas 
  lime- 
  

   stone. 
  Sink-holes 
  are 
  scattered 
  abundantly 
  over 
  the 
  sur- 
  

   face 
  of 
  the 
  upper 
  Pecos 
  Valley 
  red 
  beds 
  east 
  of 
  the 
  Pecos 
  

   River. 
  These 
  upper 
  red 
  beds 
  and 
  gypsum 
  beds 
  are 
  also 
  

   exposed 
  along 
  the 
  east 
  base 
  of 
  the 
  Guadalupe 
  and 
  Sacra- 
  

   mento 
  mountains 
  from 
  the 
  Breaks 
  of 
  Seven 
  Rivers 
  

   northwards 
  to 
  beyond 
  Roswell. 
  The 
  northern 
  limit 
  of 
  

   outcrops 
  of 
  the 
  Pecos 
  Valley 
  red 
  beds 
  is 
  not 
  known 
  at 
  

   present. 
  Southward 
  they 
  extend 
  into 
  the 
  Toyah 
  Basin 
  

   of 
  Texas 
  and 
  eastward 
  under 
  the 
  Llano 
  Estacado. 
  On 
  

   the 
  eastern 
  flanks 
  of 
  the 
  Sacramento 
  Mountains 
  and 
  of 
  

   the 
  northern 
  Guadalupe 
  Mountains 
  the 
  Pecos 
  Valley 
  red 
  

   beds 
  lie 
  directly 
  on 
  the 
  San 
  Andreas 
  limestone. 
  

  

  The 
  Mesozoic 
  Succession. 
  

  

  Upper 
  Triassic 
  (Keuper). 
  — 
  The 
  Upper 
  Triassic 
  red 
  

   beds 
  outcrop 
  in 
  or 
  underlie 
  perhaps 
  one 
  third 
  of 
  the 
  total 
  

   area 
  of 
  New 
  Mexico. 
  In 
  the 
  eastern 
  area 
  they 
  extend 
  

   from 
  the 
  flanks 
  of 
  the 
  Sangre 
  de 
  Cristo 
  Range 
  eastward 
  

   to 
  beyond 
  the 
  eastern 
  margin 
  in 
  Texas 
  of 
  the 
  Llano 
  Esta- 
  

   cado. 
  "West 
  of 
  the 
  Pecos 
  River 
  they 
  extend 
  at 
  least 
  as 
  

   far 
  south 
  as 
  the 
  Belen 
  cut-off 
  of 
  the 
  Santa 
  Fe 
  Railroad, 
  

   while 
  east 
  of 
  the 
  Pecos 
  they 
  extend 
  southward 
  to 
  beyond 
  

   the 
  Texas 
  line. 
  The 
  Trias 
  can 
  be 
  roughly 
  divided 
  into 
  

   a 
  lower 
  coarser 
  member 
  with 
  conglomerates 
  and 
  with 
  

   dark 
  purple 
  and 
  gray 
  sandstones 
  and 
  fine 
  sands 
  charac- 
  

   terized 
  by 
  the 
  abundant 
  occurrence 
  of 
  mica, 
  and 
  an 
  upper 
  

   member 
  of 
  brick-red 
  and 
  gray 
  fine 
  sands, 
  sandstones 
  and 
  

   sandy 
  clays. 
  The 
  upper 
  member 
  has 
  yielded 
  no 
  fossils 
  

   and 
  may 
  not 
  be 
  Triassic. 
  

  

  The 
  Upper 
  Triassic 
  sediments 
  are 
  entirely 
  of 
  terres- 
  

   trial 
  origin, 
  in 
  the 
  main 
  river 
  and 
  stream 
  deposits 
  and 
  to 
  

   a 
  subordinate 
  extent 
  seolian. 
  They 
  contain 
  bones 
  of 
  

   Phytosauria 
  and 
  Labyrinthodontia, 
  shells 
  of 
  Unios 
  and 
  a 
  

   large 
  amount 
  of 
  silicified 
  wood, 
  plant 
  impressions 
  and 
  

  

  