. The Vermilion iron-bearing district of Minnesota : with an atlas . SAWTOOTH HILLS OF ROVE SLATE CAPPED WITH DOLERITE SILLS. AT NORTHEAST END OFROSE LAKE, INTERNATIONAL Ji. VIEW ON AN ISLAND IN BURNTSIDE LAKE, SHOWING GRANITE OF BURNTSIDE LAKE CUTTINGAMPHIBOLE-SCHISTS—METAMORPHOSED ELY GREENSTONE. UPPER HURONIAN. 393 This series of sediments has been divided by Grant, of the Minnesotasurvey into a black slate member, with a graywacke slate memberabove it. In our work no attempt has been made to discriminate betweenthese two petrographic facies of the Eove formation. They are notsep
. The Vermilion iron-bearing district of Minnesota : with an atlas . SAWTOOTH HILLS OF ROVE SLATE CAPPED WITH DOLERITE SILLS. AT NORTHEAST END OFROSE LAKE, INTERNATIONAL Ji. VIEW ON AN ISLAND IN BURNTSIDE LAKE, SHOWING GRANITE OF BURNTSIDE LAKE CUTTINGAMPHIBOLE-SCHISTS—METAMORPHOSED ELY GREENSTONE. UPPER HURONIAN. 393 This series of sediments has been divided by Grant, of the Minnesotasurvey into a black slate member, with a graywacke slate memberabove it. In our work no attempt has been made to discriminate betweenthese two petrographic facies of the Eove formation. They are notseparable by any time interval, but represent merely slight changes in theconditions of deposition. Macroscopically they are very fine-grained blackcarbonaceous slates, grading up into dark-gray graywackes of mediumgrain, with occasional bauds of material almost sufficiently pure to be calledquartzite. In no case were any conglomerates, even fine-grained ones,found associated with these. The slates are unquestionably the predomi-nant kind of rock in the Vermilion district. They are commonly veryfissile, although in places these carbonaceous rocks are fairly massive. Microsco
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectgeology, bookyear1903
