_GENERAL DOCUMENTS - C1981017 ‎(283)‎

• Permit No: C1981017
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Name: Bid Documents ‎(IMP)‎
• Media Type: D
• Archive: No

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The Upper Bowie shale submember overlies the Middle sandstone submember.
This submember contains the Dutch Creek or Middle bed seam, which is
mined only at the Coal Basin No. 2 Mine.
The Middle and Upper sandstone submembers are deltaic beach front
sandstones. These sandstones are fine to medium-grained and poor to
moderately well sorted. The Upper sandstone member is slightly coarser
in texture.
The Paonia member is about 600 feet thick in the area of the mines, and
consists of interbedded sandstone, siltstone, shale and coal beds. The
sandstones of this member are more- lenticular and" discontinuous, and
their deposition represents a more terrestrial origin than the sandstones
of the Bowie member. There are six irregularly distributed coal seams
within the general area of the mines. These seams are, in ascending
order, the Placita, the Sunshine, the Anderson, the Lake Ridge, the
Thompson, and the Stony Ridge seams.
The North Thompson Creek No. 3 Mine is located in the Anderson seam.
This is the only active mine in a Paonia member coal . In addition to
these minable seams, the Paonia member contains several thin, lenticular
seams.
The Upper Barren member consists of between 2,000 and 2,500 feet of
lenticular sandstones and gray shales. The lenticular sandstones
represent terrestrial stream channel deposits.
The Tertiary Age Wasatch Formation - Ohio Creek conglomerate,
unconformably overlies the Hesaverde Group. This formation outcrops west
of the permit areas of the mines. The Wasatch consists of up to 5,800
feet of interbedded claystone, siltstone, sandstone, and conglomerate.
The Ohio Creek conglomerate consists of about 400 feet of sandstone and
conglomerate unconformably overlying the Mesaverde Group.
The sedimentary strata in the southern end of the Grand Hogback Monocline
have been injected by igneous dikes, sills, and a laccolith. The coal
beds in the Coal Basin Mines have been naturally coked as a result of
this igneous activity.
Unconsolidated Pleistocene gravel deposits occur as glacial remnants
capping some of the ridge tops.
The alluvia of the tributaries to the roaring Fork River (e.g. , Fourmile
Creek, Thompson Creek, and Coal Creek) are generally thin, intermittent
and, for the most part, restricted to the immediate stream channels. The
most extensive alluvium occurs at the confluence of two or more
tributaries.
The alluvium of the Roaring Fork River consist of young stream, terrace,
and ouLwash gravels. The thickness of these ,gravels range up to 10O feet.