2014-07-03_PERMIT FILE - C1981035A (4)

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3) Depositional Model of the "A" Seam a) Depositional Floor Trends: The primazy paleotopography or depositional platform upon which the coal formed extends to the Point Lookout Sandstone Formation. While the drilling did not reach this deep, it is assumed to be the reason for the major regional trends present within the azea (i.e., major coal seam splits and primary sandstone drainage channels). Upwazd from this sequence are the "B" Seam coals that are thin and laterally discontinuous throughout much of the azea. The number of thin coal seams present represent a rapid transgression sequence with abundant sediment (possibly braided sandstone channels) being deposited. Examining the "B" Seam isopach from the "National King Coal, Inc. Geologic Report" (Henderson, 1995), it is easy to see the narrow, lateral extent of the deposits extending both N55 W and N35E, which aze the predominant structural and depositional trends. The narrow deposits of coal aze approximately 2000-3000 feet wide and 5-6 feet thick, with numerous thin to lazge partings present. Note: In such an extremely variable, depositional sequence, such as the "B" seam deposits, individual seam correlations are often very d~cult to establish and it is imperative to map the relationship of the fluvial sandstone channels • surrounding the coals. It is highly probable that the several thicker coal trends do not correlate laterally into each other, but are separate coal `pods" defrned by the sandstone channels around them, with possible splitting and merging of thinner coal seams. Those ridges of coal deposition probably reflect changes in thickness, lithologic character or even structure within the Point Lookout Sandstone below the "B" Seam coal (i.e. basin compaction features). However, they also set up the chazacter of the deposits that will become the depositional platform of the "A" Seam. From the drilling data, the sequence between the "B" Seam coals and the "A" Seam is impacted by numerous fluvial sandstone channels (possibly braided). These sandstone channels most likely were attracted to the structural lows surrounding the thicker "B" Seam coal deposits. It is upon these variable fluvial deposits that the "A" Seam coal was deposited and that the character of the coal was established (e.g., sulfur and ash trends). Of special interest is the immediate floor character of the northern mazgin of the project azea. There is a very distinct sandstone present directly below (within 1-2 feet) the coal seam. The sandstone ranges from 10-12 feet thick and appears from the geophysical logs to be of very uniform grain size, suggesting a barrier beach sand deposition. The sandstone may represent a lower tongue of the above Cliff House Sandstone Formation, which would increase in thickness and merge to the north, The coal seam thickness supports this idea; the coal seam "pod" very quickly splits and thins where this sandstone is present and also the Cliff House Sandstone is closer to the top of the remaining thin