subsurface geology and coal resources of the pennsylvanian system ...

44 ILLINOIS BASIhT C014L RESOURCES
L7 Areo where Pennsylvonion l~es on K~nko~d 0 Produc~ng well (rotary)
1_! Area where Pennsylvanian lheson Degon~o -+ Dry hole (rotary), 9 Dry hole (churn)
Closely - spoced control ore0
to Polestme
350 County number
Areo where Pennsylvan~anl~es on Middle U Hole portly logged by Survey Scale of M~les
Menord 0 - 1 2 3 4
- = z
*.I&
FIG. 5.-Isopach map showing variation in interval between No. 6 coal bed and the base of the
Pennsylvanian system and pre-Pennsylvanian areal geology in Clay County.
STRATIGRAPHIC RELATIONS OF
THE BASAL PENNSYLVANIAN
The stratigraphic relations of the basal
Pennsylvanian beds are shown by a map
which combines the pre-Pennsylvanian areal
geology and isopachs showing the variation
in interval from the base of the Pennsylvanian
to No. 6 coal bed (fig. 5).
The geological map shows the Pennsylvanian
beds overlapping Chester beds from
the top of the Menard limestone (middle
part of the Menard formation) to the upper
Kinkaid limestone, with a total relief on
the Chester surface of about 250 feet. The
Chester formations which occur in contact
with the base of the Pennsylvanian have
been grouped together on the map as follows:
1) upper Kinkaid, 2) middle and
lower Kinkaid, 3) Degonia, Clore, and
Palestine, 4) Menard.
Several significant features are revealed.
The upper Kinkaid is shown as confined to
a narrow continuous area lying along the