2020-06-04_PERMIT FILE - C1981008 ‎(39)‎

• Permit No: C1981008
• IBM Index Class Name: Permit File
• Doc Date: 6/4/2020
• Doc Name: Geology Description
• Section_Exhibit Name: Section 2.04.6 Geology Description
• Media Type: D
• Archive: No

• Topographic features within the permit area include gentle southwest facing slopes; gentle rolling
upland hills and ridges; old terraces, benches, and mesas; and shallow drains (ephemeral) and
sloughs which feed Tuttle Draw (perennial).
Bore Hole and Core Hole Analysis. Attachment 2.04.6-1 (previously Peabody Appendix 6-1)
contains numerous lithologic and geophysical drill logs for the permit area which show and describe
the lithologic characteristics and thickness for each coal seam and associated strata. The location
and elevation of these drilling sites are also provided in the specified appendices. The location of
the New Horizon 2 drill holes for the geologic cross-sections are shown on Map 2.04.6-1, Geologic
Cross Section and Sample Locations, Map 2.04.6-7 shows the locations of all drill holes bored over
time in and adjacent to the permit boundary. The information on all Peabody holes is contained in
Attachment 2.04.6-1 (previously Peabody Appendix 6-1 ). The information on all other holes,
including abandonment status, is shown in Attachment 2.05.3(3)-10 Coal Exploration Drili Holes.
Structure. The New Horizon 2 area is located slightly north of the axis of the structurally simple
Nucla Syncline. Structure contours drawn as the top of the Lower Dakota (#2) coal seam indicate
• that the mean coal dip is 4.5 percent southwest and strike N.45° W. Minor local variations in the
attitude of these coals occur due to spuriously trending small folds and penecontemporaneous
depositional features. These slight undulations are best seen in the highwalls and mine floors of
active and abandoned mine pits in the New Horizon 1 area. The outcrop patterns and configuration
of overburden thicknesses are determined by a combination of topography and geologic structure.
Four geologic cross sections, D-D' through G-G', are shown in Map 2.04.6-2 through 2.04.6-5.
Cross sections D-D' and E-E' are oriented approximately parallel to the mean coal strike while
cross sections F-F' and G-G' are drawn nearly parallel to the mean coal dip. These cross sections
illustrate the simple structural relationships existing in the New Horizon 2 study area.
Faults were not observed during the course of mining at New Horizon 1. According to Cater
(1955), faults are generally absent along the axial portions of synclines in the Salt Anticline Region.
However, faults with relatively small displacement, (several feet), are encountered occasionally
while mining in the New Horizon 2 permit area.
• REVISED August 2006 2.04.6-6