194  BIBLIOGRAPHY    OF    NORTH    AMERICAN    GEOLOGY 
Keyes  (Charles  Rollin) — Continued. 
33.  Geology  of  the  Apache  Canon  placers  [New  Mexico]. 
Eng.  &  Mg.  Jour.,  vol.  76,  pp.  966-967,  illus.,  1903. 
Describes  the  location  of  the  placers,  the  discovery  of  the  placer  gold,  the  geology  of  the 
Sierra  de  los  Caballos  Mountains,  and  the  occurrence  of  fissure  veins. 
34.  Significance  of  the  occurrence  of  minute  quantities  of  metalliferous  minerals  in 
rocks. 
Iowa  Acad.  Sci.,  Proc.  for  1902,  vol.  10,  pp.  99-103,  1903. 
35.  Genesis  of  certain  cherts. 
Iowa  Acad.  Sci.,  Proc.  for  1902,  vol.  10,  pp.  103-105,  1903. 
36.  Comparative  values  of  different  methods  of  geologic  correlation  in  the  Mississippi 
Basin. 
Iowa  Acad.  Sci.,  Proc.  for  1902,  vol.  10,  pp.  105-107,  1903. 
37.  Note  on  block  mountains  in  New  Mexico. 
Am.  Geol.,  vol.  33,  pp.  19-23,  1904. 
Discusses  structure  and  formation  of  block  mountains  in  New  Mexico. 
38.  Bolson  plains  and  the  conditions  of  their  existence. 
Am.  Geol.,  vol.  34,  pp.  160-164,  1904. 
Describes  the  characters  of  bolson  plains  and  discusses  their  origin. 
39.  Remarkable  occurrence  of  aurichalcite. 
Iowa  Acad.  Sci.,  Proc.  for  1903,  vol.  11,  p.  253,  1904. 
Describes  an  occurrence-of  aurichalcite  in  the  Magdalena  Mountains  in  New  Mexico. 
40.  Certain  basin  features  of  the  high  plateau  region  of  southwestern  United  States. 
Iowa  Acad.  Sci.,  Proc.  for  1903,  vol.  11,  pp.  254-257,  1904. 
Describes  features  of  bolson  plains  of  New  Mexico,  and  discusses  their  origin. 
41.  Note  on  the  Carboniferous  faunas  of  Mississippi  Valley  in  the  Rocky  Mountain 
region. 
Iowa  Acad.  Sci.,  Proc.  for  1903,  vol.  11,  pp.  258-259,  1904. 
Notes  the  identity  of  many  of  the  fossils  from  the  two  regions,  although  they  have  been 
described  under  different  names. 
42.  Iron  deposits  of  the  Chupadera  Mesa  [New  Mexico]. 
Eng.  &  Mg.  Jour.,  vol.  78,  p.  632,  1  fig.,  1904. 
Describes  the  occurrence  and  geologic  relations  of  iron  ores  in  central  New  Mexico  and 
explains  their  origin. 
43.  The  Hagan  coalfield  [New  Mexico]. 
Eng.  &  Mg.  Jour.,  vol.  78,  pp.  670-671,  3  figs.,  1904. 
Describes  the  occurrence  and  geologic  relations  of  coal  beds  in  central  New  Mexico. 
44.  Unconformity  of  the  Cretaceous  on  older  rocks  in  central  New  Mexico. 
Am.  Jour.  Sci.,  4th  ser.,  vol.  18,  pp.  360-362,  2  figs.,  1904. 
Describes  the  relations  of  the  Cretaceous  rocks  to  the  underlying  formations.    Includes  a 
table  giving  a  general  geological  section  for  New  Mexico,  showing  the  sequence,  thickness, 
and  lithologic  character  of  the  geologic  formations. 
45.  Structures  of  Basin  ranges. 
Jour.  Geol.,  vol.  13,  pp.  G3-70,  5  figs.,  1905. 
Discusses  systems  of  faulting  and  the  general  geologic  structure  of  the  Basin  ranges  of  New 
Mexico,  and  the  physiographic  development  of  the  New  Mexican  region. 
46.  The  fundamental  complex  beyond  the  southern  end  of  the  Rocky  Mountains. 
Am.  Geol.,  vol.  36,  pp.  112-122,  1905. 
Discusses  age,  relations,  and  character  of  igneous  and  altered  clastic  rocks  occuring  in  the 
New  Mexican  portion  of  the  Rocky  Mountains. 
47.  Ore  deposits  of  the  Sierra  de  Los  Caballos  [New  Mexico]. 
Eng.  &  Mg.  Jour.,  vol.  80,  pp.  149-151,  3  figs.,  1905. 
Describes  the  general  geology  of  the  region,  and  the  occurence  and  character  of  lead  deposits. 
48.  Zinc  carbonate  ores  of  the  Magdalena  Mountains. 
Mg.  Mag.,  vol.  12,  pp.  109-114,  5  figs.,  1905. 
Describes  the  geology,  and  the  occurrence  and  relations  of  the  zinc-ore  deposits. 
