. Transactions. BowlderSI lie Greenstone Clay WX SCALE 1,010 FECI 1 INCH < koss-Skction Thbouob Alaska-Trkadwkll Mink and NORTHERN Side of Douglas Island. Shows relation of ore-bodies and other dikes of albite-diorite to slate andgreenstone. bodies recede from the shore toward the northwest (Fig. 6).The base of the greenstone hanging-wall strikes the shore ofthe island about a mile below the Ready Bullion mine, at firstrunning inland, and then back to a point below high-water Fig. just beyond where the southernmost body of diorite is exposedin the open pits of the Ready Bullion mine. Re
. Transactions. BowlderSI lie Greenstone Clay WX SCALE 1,010 FECI 1 INCH < koss-Skction Thbouob Alaska-Trkadwkll Mink and NORTHERN Side of Douglas Island. Shows relation of ore-bodies and other dikes of albite-diorite to slate andgreenstone. bodies recede from the shore toward the northwest (Fig. 6).The base of the greenstone hanging-wall strikes the shore ofthe island about a mile below the Ready Bullion mine, at firstrunning inland, and then back to a point below high-water Fig. just beyond where the southernmost body of diorite is exposedin the open pits of the Ready Bullion mine. Reappearingwithin a few hundred feet it bends sharply and is next exposed 1SS (JEOLOUY OK THE TRBADWBLL ORE-DEPOSITS, ALASKA. in the southeast pits of the Mexican mine. From this pointit is traceable in a nearly Btraighl Line through the Seven Hun-dred Foot and Treadwell workings, and for a distance of severalmiles beyond. In the vicinity of the mines there are no dikes of diorite onthe channel-side of the greenstone, but about a mile to thenorthwest two croppings have been noted; and Juneau island,in Gastineau channel about 2,000 ft. from the foot-wall, is com-posed of similar rock which is somewhat impregnated withpyrite. Besides the mineralization of the igneous dikes, the blackslates of the same general belt on both sides of the greenstone-band contain occasional veins and systems of quartz stringersfollowing the structure. Veining of this sort has been particu-larly noted alon
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Keywords: ., bo, bookcentury1800, bookdecade1870, booksubjectmineralindustries
