The Noatak-Kobuk Region, Alaska, Issues 536-539

50 cents A. H. Brooks acres Alaska Alatna River Alatna Valley Bay Horse bedrock biotite bowlders Bulletin 442 camp of August canyon Carboniferous character coal coal beds coal land conglomerate Cretaceous deposits depth determined Devonian district drainage entry Eocene feet feldspar field fossils Geological Survey geologist glacial glaciers gold granite gravels hills igneous rocks intrusive irrigation John River Kobuk Kobuk basin Kotzebue Sound Koyukuk land classification Land Office laws limestone localities lode lower lowland Mendenhall miles mineral mining Mountain mouth NOATAK RIVER Noatak sandstone Noatak-Kobuk region nonmineral numerous occur outcrop Paleozoic phosphate places probably prospectors public lands quadrangle quartz veins reconnaissance schistose schists Schrader Seward Peninsula Shungnak slopes specimens Squirrel River Stat stream structure surface thickness tion topographic tributary U. S. Geol upper valley withdrawal Yukon Yukon-Tanana region Zane Hills