Metalliferous lode deposits of Alaska

Abstract

An important factor in any rebirth of metal mining in Alaska will be a thorough appraisal of the metalliferous lodes already known in the State. Any such appraisal probably will depend, a t least in part, on an inventory of these 1 deposits and a knowledge of their geology. This report summarizes from repoAs of Federal and State agencies published before August 31, 1965, the geology of Alaska's metal-bearing lodes, including their structural or stratigraphic control, host rock, mode of origin, kinds of .Q minerals, grade, past production, and extent of exploration. I n addition, the lists of mineral occurrences that accompany the 35 mineral-deposit location maps constitute an inventory of the State's known lodes. A total of 692 localities where m&alliferous deposits have been found are shown on the maps. The localities include 1,739 mines, prospects, and reported occurrences, of which 821 are described individually or otherwise cited in the text. ORGANIZATION AND METHOD OF PRESENTATION This report is arranged by mining regions and mining districts, geographical subdivisions whose boundaries, defined by the U.S. Bureau of Mines (Ransome and Kerns, 1954), mostly follow major drainage divides (pl. 1). We adopted this classification, which is largely independent of geology, chiefly for convenience and simplicity, but it also minimizes the tendency to sort our data by metallogenic provinces or to speculate on regional geologic controls that have governed the formation of certain mineral deposits-subjects that are beyond the scope of this report. The 14 mining regions and the 67 districts included in them are arranged in alphabetical order and are accompanied by maps showing the locations of all known mines, prospects, ,and reported mineral occurrences. To conserve space, adjoining districts that are small or contain only a few lode mineral localities, are combined on single maps. Each locality has been given a number that corresponds to a citation in the text. The descriptions of the lode deposits of each mining region or each district (in the case of the Yukon River region) are prefaced by brief summaries of the physiography and 4 METALLIFEROUS LODE DEPOSITS OF ALASKA large enough to appear on the map, but in some cases this was not possible. All geographic names cited in this report, however, do appear on I; 250,000-scale (1 inch=approx. 4 miles) or larger scale topographic maps published by the U.S. Geological Survey; the reader who is interested in locating a deposit or geologic feature precisely is urged to consult the appropriate topographic map. (A11 map sheets referred to herein are 1 : 250,000-scale topographic maps published by the U.S. Geological Survey. Indexes to these maps and copies of the topographic sheets may be obtained from the Geological