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

HAMILTON COUNTY
TABLE 10.-DATA ON INTERVALS BETWEENO. 6 AND NO. 5 COAL BEDS AND BETWEEN
No. 6 AND "LITTLE MENARD" LIMESTONE OF CHESTER SERIES
Location
T. S. R. E.
Interval
No. 5 to No. 5
coal bed
Range
Av.
Number
of drill
holes
Interval
No. 6 coal bed
to "Little Menard"
Range
Av.
Number
of drill
holes
Haven, Gallatin County:' It is the first
conspicuous limestone encountered in drilling
and lies 480 to 580 feet above Herrin
(No. 6) coal bed. The interval increases
toward the east (fig. 21). The Shoal Creek
limestone, about 5 to 12 feet thick, generally
forms a single bench but appears locally in
two benches. In drill cuttings the rock
is white to light tan and finely granular
to crystalline. It becomes somewhat sandy
near the eastern boundary of the county,
and a thick sandstone member lies across
the position of the limestone in the southern
part of the county. The limestone is
generally underlain by shale, described
sometimes as black for a few feet, overlying
a thin coal bed. In those drill hclcs where
coal was recorded, the interval between the
coal bed and the Shoal Creek limestone is
about 20 feet.
Cutler coal bed.-A coal bed, 1 to 2 feet
thick and about 65 to 75 feet above the
Herrin (No. 6) coal bed, underlies most
of the county. Locally the interval increases
to $5 to 95 feet where a large part
5 DeWolf, F. W.. Coal investigations in the Saline and
Gallatin field: Illinois Geol. Survey Bull. 5. p. 218, 1905
of the intervening strata consists of sandstone.
The correlation of this coal bed with
the Cutler coal bed of Perry CountyG is
tentative, but it occupies the approximate
position of a coal bed underlying the Cutler
limestone. The Cutler limestone is usually
not encountered in drill holes in Hamilton
County, but members of the Survey have
observed it in drill cores from holes as far
east as the vicinity of Eldorado and in outcrops
along the Illinois Central Railroad in
Saline C~unty.~
Bankst on Fork 1ime~tone.~-This limestone,
2 to 6 feet thick, occupies an intermediate
position between the Cutler coal
bed and the Herrin limestone and lies 40
to 50 feet above the No. 6 coal bed. Well
cuttings are light gray to tan with a
slightly granular texture, locally becoming
somewhat shaly and nodular. It is only
sparingly fossiliferous. It is not immediately
underlain by black shale or a coal bed
F13ell, A. Il., Ball, C. G., and McCabe, L. C., Geology
of the Pinckneyville and Jarnestown areas, Perry County,
Illinois: Illinois Geol. Survcy, Illinois Petroleum 19, p. 3,
1931.
Personal communication from G. H. Cady.
Cady, G. H.. The areal geology of Saline County: Trans.
Illinois Acad. Sci., vol. 19, p. 262, 1926.