. The Vermilion iron-bearing district of Minnesota : with an atlas . - of long extensionin any one direction, as is so markedly the case in the lakes of the other. Fia. 22.—Settiun through the Eove shitcs. with intercaUited Logan sills south of Gunflint Lake. portions of the Vermilion district. On the contrary, they spread out in alldirections, sending off luimerous bays, some of which a)-e very long andnarrow, and all very irregular in shape. The Logan sills exercise a very material influence upon the topographyof that portion of the district north of the gabbro in which the} occur. Itwill be
. The Vermilion iron-bearing district of Minnesota : with an atlas . - of long extensionin any one direction, as is so markedly the case in the lakes of the other. Fia. 22.—Settiun through the Eove shitcs. with intercaUited Logan sills south of Gunflint Lake. portions of the Vermilion district. On the contrary, they spread out in alldirections, sending off luimerous bays, some of which a)-e very long andnarrow, and all very irregular in shape. The Logan sills exercise a very material influence upon the topographyof that portion of the district north of the gabbro in which the} occur. Itwill be recalled that the Upper Huronian (Animikie) sediments in this vicin-ity have a iiionoclinal dip to the south. The sills have been injected essen- THE KEWEENAWAN. 401 tially parallel to the bedding- of the sediments, although occasionally theyare found cutting across the beds at low angles. Erosion has been mostactive in this portion of the district in a direction parallel to the strike ofthe beds, and consequently most of the large valleys trend in agreementwith these, approximately east and west. The resistant sills now form thecaps of the ridges, the s
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectgeology, bookyear1903
