PORTLAND,  NATURAL,  AND  PUZZOLAN  CEMENTS. 
CEMENT  RESOURCES  OF  THE  CUMBERLAND  GAP  DISTRICT, 
TENNESSEE-VIRGINIA. 
Hv  Ki>\\  i\  <     E<  mi  . 
al  statement.  In  January,  1906,  a  shorl  time  was  -pent  in  the  examination  of  the 
cement  resources  of  the  Cumberland  Gap  district.  Here,  in  Claiborne  County,  Trim., 
and  Lee  County.  Ya..  heavy  beds  i>(  nonmagnesian  limestone  and  shales  are  exposed  along 
itheastern  flank  of  Cumberland  Mountain.  Near  Cumberland  Gap  these  beds  are 
particularly  well  located  from  a  cemenl  manufacturer's  point  i>(  view,  being  accession 
to  two  railroads  and  within  9  miles  of  the  important  Middlesboro  coal  district.  These 
advantages  seemed  to  justify  careful  examination  n\'  the  area  and  the  present  brief  report 
summarizes  the  writer*-  conclusions  in  regard  to  the  matter.  It  i-  a  pleasure  to  acknowl- 
edge the  courtesies  extended  by  the  officials  of  the  American  Association,  the  Virginia 
[roi  .  Coal,  and  Coke  Company,  the  Louisville  and  Nashville  Railroad,  and  the  Southern 
Railway.  Mi.  •'.  II.  Bartlett,  of  the  American  Association,  furnished  detailed  map-  of 
the  district  and  some  analyses  of  the  lime-tone-  and  -hales,  and  also,  by  request,  had 
several  sections  measured  and  platted  by  his  engineers.  Further  analyses  of  the  lime- 
stone-, -hale-,  and  iron  ores  of  the  district  were  obtained  from  the  manager  and  chemist 
of  the  Middlesboro  plant  of  the  Virginia  [ron,  Coal,  and  Coke  Company. 
>f  flu  district.  The  rocks  of  the  district  include  Silurian.  Devonian,  and  Carl 
boniferous  formation-,  dipping  mostly  to  the  northwest  al  angles  of  15°  to  35°.  The  secj 
tioii  exposed  in  the  district,  from  above  downward,  may  be  generalized  as  follow-: 
berland  Gap. 
Tl.ic 
Coal  Measures:  Shales  and  sandstones  with  coa 
Lee  conglomerate:  M  e  and  conglomerate 1,000  1,100 
Pennington  shale:  Greenish  shales  and  thin  sandstone 
Nev.man  limestone:  Beavy-bedded  blue  and  gray  limestone 
Grainger  shale:  Gray  to  greenish  shales 
Chattanooga  shale:  Black  carbonaceous  shales :  ' 
Rockwood  formation:  Shales  nes,  with  beds  of  red  hematite 400-    7ih) 
Areal  distribution  of  flu  formations-  Of  the  formation-  above  tabulated,  the  Coal  Mea>- 
ures  outcrop  only  in  the  area  northwesl  of  Cumberland  Mountain.  The  crest  and  north- 
west flank  of  this  mountain  are  formed  by  the  massive  beds  of  the  Lee  conglomerate. 
Underlying  the  conglomerate,  near  the  top  of  the  southeastern  flank  of  the  mountain,  is 
a  relatively  thin  bed  of  the  Pennington  shale.  Below  this,  and  usually  forming  the  middle 
part  of  the  slope,  are  heavy  beds  of  Newman  'Lower  Carboniferous)  lime-tone.  The 
Grainger  and  Chattanooga  shale-  outcrop  on  the  lower  slopes  of  the  mountain  and  in  the 
valley  (Poor  Valley)  at  its  foot:  while  the  Rockwood  beds  commonly  make  up  the  Poo* 
Valley  Ridge  just  southeast  of  this  valley. 
"  374 
