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EY The best coal is in the lower part of the seam. Its rank is medium volatile bituminous.

Six feet above the Knight seam is a 1.2-foot seam, Eleven feet higher is 0.4 foot of coal overlain by 0.4 foot of shale and 0.4 foot of coal. Twelve feet higher still is a 1.2-foot seam. No others were noted between this seam and the Galloway sandstone. Some beds, however, are concealed in the shore section. i ¢

The beds between the Galloway and Cust Island sand- stones contain very little coal. About 0.5-foot of coal is found 10 feet above the Galloway sandstone and a small vari- able seam, a little less than 1 foot thick, occurs immediately below the Cust Istand sandstone. ,

-DUNLEVY GREEK-CUST CREEK AREA Geology

-.° Only a reconnaissance examination was made of the territory between Dunlevy and Cust Creeks. Large seams have been reported, but none was found within a few miles of the road...

Topographically the area includes the west side of Butker Ridge and the southern parts of the valleys of Dun- levy, Gravel Hill, and Cust Creeks,

Butler Ridge is underlain by the Dunlevy formation, and the lower parts of Dunilevy. and Gravel. Hill Valleys by the Gething formation, Both formations are exposed in Cust Valley. The structure includes the steep west limb of a flat-topped anticline on the west side of Butler Ridge, and the more gentle slopes of the same limb in Dunlevy and Gravel Hill Valleys. Dips on Butler Ridge are from 40 to 70 degrees southwest, and in Dunlevy Valley from 2 to. 5 degrees south- west. The structure ‘On. AMEN: Creek is faulted and dips are tess regular.

Coal Seams

No seams thick enough to mine are exposed in the canyon of Dunlevy Creek, or in the canyon or upper reaches of the east fork of Dunlevy Creek and its tributarie.. Only thin seams were found on Gravel Hill and Cust Creeks.

At and near the Packwood mine, at the south end of a spur from Butler Ridge, two thin seams occur in the upper conglomerate—bearing part of the Dunlevy formation.

The No. 1 seam, worked in the mine, has an average thickness of 30 inches in the upper level and 20 inches in the lower level. The lower 10 inches of the seam is finely crushed, and movement is also indicated by slickensides on both walls. The foot-wall rock is silty shale and the hang- ing-wall consists of hard, massive sandstone. The seam was sampled at the face in both levels. Analyses are as follows: