COAL   BETWEEN    GALLINA   AND   EATON    SPRING,    N.    MEX.         337 
the  surrounding  desert  country.  The  water  issues  from  beneath  a 
massive  sandstone,  and  the  flow  in  August,  1907,  was  about  1 
gallon  per  minute.  These  are  the  only  localities  worthy  of  individual 
mention  here,  but  there  are  numerous  Mexican  ranches  along  the 
west  foot  of  the  Sierra  Nacimiento  between  Gallina  and  Cuba. 
The  Sierra  Nacimiento  is  a  more  or  less  continuous  north-south 
mountain  ridge,  with  an  average  elevation  of  about  9,500  feet,  or  about 
2,500  feet  above  the  surface  of  the  plateau  country  to  the  west. 
Northeast  of  Cuba  the  ridge  rises  to  an  elevation  of  10,162  feet,  and 
is  known  as  San  Pedro  Mountain.  An  abundant  supply  of  pure 
water  flows  perennially  from  the  slopes  of  this  mountain,  the  drainage 
on  the  north  passing  down  as  the  source  of  Gallina  River  and  on  the 
southwest  as  the  source  of  Rio  Puerco.  Gallina  River  flows  north- 
ward for  about  16  miles,  then  turns  eastward  to  Rio  Chama,  a  tribu- 
tary of  the  Rio  Grande.  Rio  Puerco  flows  southward  and  is  also  a 
tributary  of  the  Rio  Grande.  On  the  west  the  mountain  presents  a 
bold  front,  and  along  its  slopes  the  sedimentary  rocks  are  steeply 
inclined  and  form  hogbacks.  At  some  places  the  slopes  are  exten- 
sively covered  by  bowlders  and  wash,  principally  granite  and  granite 
porphyry  from  the  mountain  mass.  In  the  vicinity  of  Gallina  the 
Tertiary  beds  overlap  the  Cretaceous  and  lower  sedimentary  strata, 
and  in  places  rest  against  the  crystalline  rocks  of  San  Pedro  Mountain. 
These  Tertiary  beds  include  the  Puerco,  Torrejon,  and  Wasatch  forma- 
tions, which  cover  the  broad  plateau  country,  stretching  westward  to 
San  Juan  River.  This  region  is  a  dry,  barren  expanse  of  highly  colored 
mesas  and  badlands,  known  as  the  Nacimiento  Desert.  The  high 
portion  of  the  plateau  along  the  Continental  Divide  west  of  Gallina 
and  east  of  Canyon  Largo  is  named  on  the  Wheeler  map  "Los  Altos 
del  Utah. "°  The  country  between  Cuba  and  Raton  Spring  presents 
a  series  of  Laramie  and  Tertiary  escarpments  that  have  receded  to 
varying  distances  northward.  These  escarpments  have  been  dis- 
sected into  numerous  outliers  and  mesas  with  gentle,  intervening  dip 
slopes  in  the  form  of  sage-covered  plains.  Interspersed  with  these 
features  are  numerous  canyons  and  deep  arroyos.  The  principal 
drainage  way  of  this  area  is  the  Arroyo  Torrejon.  This  stream  bends 
along  the  Atlantic  side  of  the  Continental  Divide,  which  crosses  the 
territory  in  a  northeast-southwest  direction.  In  times  of  heavy 
rainfall  there  are  numerous  small  lakes  in  the  area,  which  are  readily 
soaked  up  or  dry  away  in  the  periods  of  drought  that  follow.  There 
are  no  ranches  in  the  area  west  of  Cuba,  but  only  scattered  tents  of 
Mexican  sheep  herders  or  hogans  of  a  few  nonreservation  Navajoes. 
The  area  is  not  subdivided  by  land  lines;  however,  some  surveying 
is  at  present  being  done  in  the  vicinity  of  Cuba. 
a  U.  S.  Geog  Surveys  W.  100th  Mcr.,  Atlas  sheet  No.  60. 
71497— Bull.  341—09 22 
