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Anticlines form the limbs of the Bourg Syncline. This syncline is asymmetric, strikes N50°W and plunges 4 to 8 degrees to the northwest. The entire Bourg Strip life-of-mine plan area is within the Bourg Syncline. The Ballinger Anticline structurally separates the Bourg Syncline from the Johnny Moore Syncline. The Johnny Moore Syncline is an asymmetric syncline, strikes N45°W, plunges to the southeast, and is flanked on the west by the McCallum Anticline. The intense folding of the local rock strata has produced many faults in the general area. Faulting is more pronounced at the noses of synclines and anticlines. Stream channels have developed in several fault zones. Two normal and one reverse fault exist within the Bourg permit area, at the nose of the Bourg Syncline. Wyoming Fuel Coal Company has encountered 5 faults at the Canadian Strip Mine. This mine is at the nose of the McCallum Anticline. However, only 2 normal faults are known to exist in the entire Marr Strip, which is on the western limb of the McCallum Anticline. To date, the only faults that produced pit inflows were the faults encountered at the Canadian Strip pit. North Park contains 15,000 feet of Triassic to Quaternary aged sedimentary rocks. Late Cretaceous and Early Tertiary sediments account for almost the total. The Pierre shale is the oldest sedimentary stratum exposed in the general area of the mines. This formation is Late Cretaceous in age and composed of a 4,000 foot thickness of marine shales and minor amounts of siltstone and sandstone beds. The upper Pierre shale contains a sandstone member which forms the unconformable contact with the overlying Coalmont Formation. Due to the marine origin of Pierre shale, the salinity is high in this stratum. The coal seams of the North Park area lie in the Coalmont Formation of Early Tertiary Age. The formation is composed of between 4,000-6,000 feet of terrestrial interbedded shales, mudstones, sandstones, and coals that unconformably overlie the Upper Sandstone member of the Pierre Shale Formation. Three coal seams or zones exist within the Coalmont Formation in the general area of the mines. These are, in ascending order, the Sudduth seam, Hoyle seam and Capron seam. The Sudduth seam is the thickest and most widely mined seam in the region. This seam is at the base of the Coalmont Formation near the unconformable contact with the Pierre Shale. All three mines in the North Park Coal Field have mined the Sudduth coal seam. The coal in this seam is a subbituminus B coal with a low sulfur content (0.25%) and a heat output of about 10,800 BTU's per pound. The thickness of this seam varies between 10 and 70 feet. Bourg Strip Mine. C-81-021 5 April 21, 1993