Bulletin of the United States Geological Survey--The Rampart Gold Placer Region, Alaska . rt slate and quartzite;tuffaceous greenstones which predominate in the lower part of the valley are over-lain near the mouth by Kenai sandstones and conglomerates. The tuffs containsome rounded pebbles, and a hole 228 feet deep was sunk in them under theimpression that they belonged to the frozen muck and gravels of the creek. Therocks are much jointed and contain many small veins of quartz and calcite. Pyriteoccurs at many places. The gravels of the creek are 2 to 12 feet thick and are mostly diabase, sl
Bulletin of the United States Geological Survey--The Rampart Gold Placer Region, Alaska . rt slate and quartzite;tuffaceous greenstones which predominate in the lower part of the valley are over-lain near the mouth by Kenai sandstones and conglomerates. The tuffs containsome rounded pebbles, and a hole 228 feet deep was sunk in them under theimpression that they belonged to the frozen muck and gravels of the creek. Therocks are much jointed and contain many small veins of quartz and calcite. Pyriteoccurs at many places. The gravels of the creek are 2 to 12 feet thick and are mostly diabase, slate, andchert pebbles from the bed rock, with many heavy bowlders of quartzite, occasion-ally reaching 3 feet in diameter. These larger bowlders are residuals from thegravels of the old bench through which the valley is cut. Much of the diabasegravel is angular or subangular. The muck over the gravel varies in thickness from1 foot in places along the stream to 40 feet or more where the small streams pourtheir debris upon the valley floor. U. S. GEOLOGICAL SURVEY BULLETIN NO. 280 PL. V. ,1. AUTOMATIC DUMP GATE DISCHARGING, CLAIM NO. 3 BELOW, LITTLEMINOOK CREEK.
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