The Ketchikan miner., 1908-11-07
lary statement of the mineral resour.

nary statement of the mineral resour- ces of the three most important min- has heen issued, that on the Juneau district having he. sent out in 1906. Because oI its important mining inter- est, southeastern Alaska was one of the first fields in the territory to be l investigated by the Geological Survey, but up to 1902 the work in this region had not advanced beyond the cursory examination ot some of the more i'm portant districts. In 1902 lopo- graphic survey of small area near Juneau was completed, and was fol- lowed during 1908 by the geologic mapping of the same area and the eX- tension of geological reconnaissance over a considerable adjacent region. The report just issued einbodies the result of the eXteus On oi these studies southward to tine southern boundary of the territory. The main object of the preliminary publication is to meet the needs of miners and prospeetors, and the reports include only so much of the general geology as is necessary to the understanding of the occurren- ee of the commercially valuable min- eral deposits. \ more complete eX
 position of the geology will be present. ed when the field has been more ex- haustively studied, and a final analysis of the various problems connected with the genesis and oecurrene of the ores must also await detailed surveys. Such geologic surveys must be preced- ed by topographic mapping, and hence can be carried on very slowly.
 The report covers q land area esti- mated at II, 50o square miles, and in- ciudes the portion of the mainland ex- tending from Portland Canal on the south to line running due east from Cape Fanshaw to the international boudary, and the islands of the Alex ander archipelago south of Frederick sound and Sumner strait. The hetch |
 from the Wrangell district to the north by line through Sumner strait around the north end of Prince of 1 Wales island, down Clarence strait as far as Ernest sound, un Ernest sound. along Bradtield Canal eastward, and across the mountain range to the in- ternational boundary
 The field worK in tine Keschikan district was begun by A. H. Brooks in 1901, and a preliminary report was issued the following year. The present report is the work of r. E. Wright and C. ". Wright, who were engag
 ed m field investigations of the re- zion during 1895 and l9o6 Three maps accompany the report of Messrs. Wright and Wright. Dane of these,
 g neral map on a scale oi about 10 l miles to the inch, includes both the
 ketchikan and Wrangell districts, and is compiled from charts of the United States coast and geodetic sur vey. supplemented by sketch maps
 made by the authors of the report. On this map the geology is represent ed. and also the location of the mines and prospects. On the other two maps, which are contour sheets of the mainland portion of the province, the geology is plotted in greater detail. 1 Sketch maps introduced through the text to show the position of mining properties were furnished. for the most part. by the mine owners themselves. Though the results obtained by the rapid reconnaissance work over the urge area covered by this report do not present the refrementS of detail ed work. it is believed that their presentation will give fairly correct l impression as to the distribution. character and relative importance oi the ore bodies and ore-bearing forma- tions in this section of Alaska.