2020-10-27_PERMIT FILE - C1981035 (29)

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• King Coal Mine lies within the center of the block, the thicker coal "pod" lies to the west of center (figure 9). It can be assumed that the coal deposit is not uniform, but that the higher, depositional center of the deposit lies along the western margin of the block and that the coal gradually thins to the east with increasing sediment influence (e.g., partings and higher sulfur trend, figure 10). If the model holds true, then the gradual decline of the coal deposit to the east is opposite to a sharp decline in the thick coal "pod" along the western margin. This could occur by an increase in influence of the Cliff House Sandstone tongue from the northeast (presently visible on the geophysical logs immediately below the "A" Seam in the drill sites on the northern edge of the project area). Another explanation would be the presence of a large fluvial sandstone channel system flowing from the southwest along the Mancos River lineament trend (parallel to Cherry Creek). The northern edge of the thick coal "pod" is controlled by the northwest -southeast trending strand line (beach sand, figure 10). Beaumont has observed that "the transgressive nearshore and beach facies tend to be lacking in the crossbedded massive sands that are associated with some typical beach deposits" (Beaumont, 1971). This implies that the sandy beach sequences are likely to be in close proximity to the peat deposits, resulting in rapid depositional changes. The data supports this idea, and the coal quickly thins at the northern margin of the deposit. The southern edge of the deposit should have a gradual thinning of the coal similar to the eastern margin, however the distance of depositional change would be greatly decreased (e.g., short axis of the coal deposit normal to the strand line). Variations of this northwest to southeast oriented wedge shaped deposit of coal, bounded by strong structural lineament features, is common in the depositional models which I have created along the western margin of the San Juan Basin. Note: While I feel the above interpretation is sound, the potential extension of the coal reserve to the west is "my best guess " and requires additional information. I have seen lineament trends become the center axis of the coal deposit, however I feel the strength of the Mancos River lineament and the nature of the depositional environment would exclude this possibility. The strength of the lineaments present and the area's proximity to the uplifted La Plata Mountains suggest the potential presence of faults or at least weakened rock trends. While there is no evidence of faulting present, it is within the primary depositional directions and lineament trends that structure may occur. Since no strong lineament trends criss-cross the project area, only localized weak roof rock and compaction fractures are anticipated.