PERMFILE60920

• Permit No: C1981033
• IBM Index Class Name: Permit File
• Doc Date: 2/1/1981
• Doc Name: Permit
• Section_Exhibit Name: 1981 ORIGINAL APPLICATION
• Media Type: D
• Archive: No

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2.04.6(2)(a)
The termination of coal depositing environments in the lower
coal member was the direct result of a diminished sediment `
supply creating a disequilibrium condition whereby basin
subsidence was greater than sediment supply. This caused a
small scale onlap (transgression) of the seaway across the
area from east to west, small scale because the deep water
facies (shales) of this transgression are not well developed
in the area. The sandstone at the top of the lower coal
member (often immediately below the D seam) represents the
renewed regression of the seaway and the formation of a second
barrier-beach and delta complex. This delta is though to
have been situated slightly to the north of the mine area,
with the barrier-beach extending southward. The evidence for
this is shown on the northern edge of the lease (and further to
the north) where there is a general splitting of some seams,
the appearance of one or more rider seams, and lack of continuity
of coals in the upper coal member (D, E and F seams). From
north to south there appears to be an increase in the continuity
of the coals in the upper member, supporting evidence for the
presence of this barrier-beach to the east, which again allowed
the necessary stable conditions to e;;ist during deposition of
the D, E and F seams.
In the barre~ member (above the F seam) there appears to be
evidence of more landward fluvial environments in the lithologies.
This increased fluvial activity resulted in a rapid influx of
sediment, thus creating conditions of disequilibrium between
sediment supply and basin subsidence. The seaway was now forced
to retreat much further to the east so that the barren member
was deposited under overwhelming conditions of continental
influence.
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