EASTERN SANDSTONE ON THE ONTONAGON RIVER. 359 
together by shifting waters—i. ¢., one grain enters a depression in the side 
of another. Again, it is difficult to see why the supposed hot waters 
should have selected this one sandstone for leaching, removed as it is, now 
at least, from the heating lava-flows; while the beds directly intercalated 
with these flows should in no instance show any signs of such a leaching. 
Although Mr. Wadsworth seems to have felt it necessary thus to explain 
away the peculiarly quartzose character of the Eastern Sandstone as com- 
pared with the sandstones of the Keweenawan, this lithological dissimilarity 
seems to me really rather more in favor of his peculiar view, as to the 
structural relations of the Eastern Sandstone, than against it. 
Southwestward from the vicinity of Torch Lake, the Eastern Sand- 
stone may be seen in close proximity to the Keweenawan diabases, at a 
number of places, and always with the same relatively quartzose character, 
and horizontal position or southeasterly dip. Pumpelly figures such an 
occurrence, for instance, in the N. W. 4, Sec. 6, T. 54, R. 33 W., on the 
south side of Portage Lake.t Again, the streams in sections 22 and 23 of T. 
54, R. 34 W., run over horizontal quartzose sandstone, and the same is true 
of the streams in the central and southeastern parts of T. 52, R. 35 W., 
where the exposures are quite large. But still farther west, on and near 
the Ontonagon River, much larger and more instructive exposures of the 
Eastern Sandstone are to be found. The occurrences here are like those on 
Béte Grise Bay—i. e., the sandstone dips away southward from the north- 
dipping Keweenawan diabases, at quite a high angle near the contact and 
rapidly grows flatter as the contact is receded from. 
Ix 
ox 
PEXKKRD 
ratetetel watateta lates 
Heweenawan Diabases. 
Fre. 32.—Section showing relation of Eastern Sandstone to Keweenawan diabase, T. 50, R. 39 W., 
Michigan. Length of section, one-half mile. 
The above section was taken by Mr. W. M. Chauvenet along the 
course of the small stream in sections 23 and 24, T. 50, R.39 W. The sand- 
1 Atlas Geol. Survey Mich., Plates XIV and XY. 
