Bulletin of the United States Geological Survey--The Rampart Gold Placer Region, Alaska . In the vicinity of the mouth of Slate Creekis a bench cut in the upturned slates and thin-bedded quartzites to a depth of 12 to16 feet and covered by 4 or 5 feet of gravel and a foot or more of muck. No gravelhas yet been found upon the benches of intermediate height, but further investiga-tion may show its presence. In its upper course the creek flows somewhat north of east for about 2 miles, andhere the topography of its valley is altogether different from that of the lower north side is a long
Bulletin of the United States Geological Survey--The Rampart Gold Placer Region, Alaska . In the vicinity of the mouth of Slate Creekis a bench cut in the upturned slates and thin-bedded quartzites to a depth of 12 to16 feet and covered by 4 or 5 feet of gravel and a foot or more of muck. No gravelhas yet been found upon the benches of intermediate height, but further investiga-tion may show its presence. In its upper course the creek flows somewhat north of east for about 2 miles, andhere the topography of its valley is altogether different from that of the lower north side is a long, gentle slope with a greater rise in the upper part, while thesouth side is steep and the stream flows near its base. The asymmetry of this partof the valley is repeated in Eureka, Pioneer, Hutlina, Omega, New York, California,and many other creeks of the region whose valleys lie in parallel or nearly paralleldirections. The rocks in the upper part of the valley are mostly closely folded slates and lime-stones. Garnetiferous schists occur at Ruby Creek, and greenstones form the bed. Fig. 1.—Diagrammatic sketch of Minook Valley. rock of the lower valley except near the mouth, where they are partly covered bythe Kenai rocks. The alluvials of the valley are said to be 10 to 12 feet thick and consist of the usualmuck (soil mixed with much vegetal matter), peaty soil, and gravel, with muchangular debris at the foot of many of the hillsides. In the middle part of the valleythey consist of about 5 to 6 feet of muck and the same thickness of gravel. Themuck thickens toward the sides while the bed rock remains about level. The graveldeposits are derived from local bed rock and contain large numbers of smoothlyrounded quartzite bowlders from a few inches to 3 feet in diameter, whose source hasbeen a mystery to many. Some of these bowlders have undoubtedly descended tothe present creek bed from the high benches already referred to, in whose gravelsthey are abundant. The outcrop of quar
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