4()4  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,   1903.  [bull.225. 
has  a  fairly  regular  shape,  with  a  south-pitching  axis.  The  character 
of  this  basin  has  been  ascertained  largely  from  the  records  of  a  very 
l.-w  deep  wells  which  show  the  position  of  the  Pittsburg  coal. 
Conditions  are  such  that  the  accurate  determination  of  the  structure 
of  this  basin  is  almost  impossible.  Few  wells  have  been  drilled  in  the 
region,  and  the  rocks  showing  at  the  surface  are  of  such  a  character 
that  actual  tracing  and  definite  correlation  are  impracticable;  there- 
lore  the  locations  of  the  structure  contours  in  this  part  of  the  map 
are  regarded  as  approximate  only,  and  subject  to  revision  when  more 
definite  evidence  is  available. 
This  syncline  has  the  same  position  with  relation  to  the  anticlines 
on  both  sides  as  the  Port  Royal  syncline  in  the  Brownsville  quad- 
rangle. But  the  Port  Royal  syncline  loses  its  basin-like  character  in 
the  vicinity  of  Fayette  City,  on  Monongahela  River,  and  the  axis 
does  not  seem  to  be  continuous  with  the  one  here  described.  The 
axis  of  the  basin  in  Greene  County  seems  to  lie  about  on  a  line 
through  Fordyce  and  Kirby  and  crosses  Dunkard  Creek  just  south  of 
the  State  line  in  West  Virginia,  about  three-fourths  of  a  mile  west  of 
Pentress.  In  order  to  have  a  convenient  appellation  for  this  struc- 
tural feature,  the  name  Whiteley  syncline  will  be  used  in  this  report. 
It  is  taken  from  the  township  in  Greene  County  in  which  the  basin  is 
broadly  developed. 
Bellevernon  anticline. — Next  to  the  Fayette  anticline  the  most  pro- 
nounced and  important  structural  feature  in  the  eastern  half  of  Greene 
County  is  the  Bellevernon  anticline.  The  axis  of  this  fold  enters  the 
county  at  Clarksville  and  pursues  a  southwesterly  direction  for  nearly 
14  miles  to  the  head  of  Dyers  Fork,  where  it  turns  south  and  gradu- 
ally flattens  out.  A  natural  continuation  of  the  axis  would  cross  the 
State  line  nearly  a  mile  west  of  Blacksville,  but  for  2  miles  west  of 
the  village  the  rocks  are  horizontal,  or  rise  to  the  east.  It  seems 
probable  that  the  anticline  disappears  soon  after  entering  West  Vir- 
ginia, if  it  crosses  the  State  line  at  all.  A  low  anticline  which  is  seen 
just  east  of  Blacksville  probably  is  the  northern  end  of  another  axis. 
The  Pittsburg  coal,  which  is  the  reference  stratum  on  which  the 
structure  contour  lines  are  drawn,  is  at  an  elevation  of  1,000  feet  where 
the  Bellevernon  anticline  crosses  Monongahela  River,  between  Belle- 
vernon and  Charleroi;  it  is  750  feet  above  tide  at  Clarksville,  and  only 
400  feet  above  tide  at  Blacksville.  It  should  be  noted  that  conditions 
were  favorable  for  the  accurate  determination  of  the  position  of  the 
reference  stratum  along  the  Bellevernon  anticline  in  Greene  County. 
The  Wavnesburg  coal  outcrops  on  Tenmile  Creek  from  the  river  to 
Waynesburg,  and  the  interval  between  it  and  the  Pittsburg  coal  is 
known.  The  depth  of  the  Pittsburg  coal  below  the  surface  is  shown 
in  150  deep  wells  along  the  anticline,  and  when  the  elevation  of  the 
well  mouths  is  known  the  elevation  of  the  reference  stratum  above 
