Northern Wisconsin advertiser. [volume] (Wabeno, Wis.) 1898-1925, 1900-05-17

The Wisconsin geological and nat
ofal history survey has issued a bull
letin on the Geography of the Region
about Devils Lake and the Dalles of
the Wisconsin, with some notes on it's
surface geology. 1t is the work Of
Rollin D. Salisbury. professor of geo.
graphic geology in the University of
Chicago, AMI Wallace w. Atwood as
sistant to Prof. Salisbury. It is di-
vided into five chapters as follows:
General geographic features outline
OF the history ofrock formations which
show themselves at the surface. gem
eral outline of rain and river erosion,
erosion and the development of stril1-
ing scenic features, the glacial period.
Thirty-eight illustrative plates are
given, some of them of great beauty.
Some interesting speculations are
made regarding the glacial epoch and
the changes it brought to this region.
Concerning DEVILS lake in the gla-
cial period the report says that while
the ice was at its maximum stand. il
rose above the moraine ridges at
either end of the lake. Between the
ice at these two points there was then
noticeable basin, comparable to that
of the present lake except that the
barriers to the north and southeast
were higher than now. The melting
OF the ice supplied abundant water.
and the lake rose above its present
level. The height which it attained is
not known, but it is known to have
risen at least 80 feet above it's present
level. This is indicated by the pres
ence of few drift powders on the
west bluff of the lake at its height.
they represent the work of a berg or
bergs which at some stage floated out
into the lake with powders attached.
Bowlders dropped by bergs might be
dropped any level lower than the
highest stand of the lake.
There was another glacial lake on
the east quartzite bluff. Like the
Devils lake in glacial time, it's basin
was an enclosure between the ice on
the one hand, and the quartZite ridge
on the other. Here the edge of the
ice, as shown by the position of the
moraine, was affected by re-entrant
curve, the two ends of which rested
against the quartzite ridge Between
the ice on the one hand and the
quartzite ridge on the other, a small
lake was formed. Its position is
marked by notable fiat The lake
mad short life, being soc0 filled up.
The irregular deposition of glacial
drift gave rise to many depressions
without outlets in which surface
waters collected after the ice had dis
appeared, forming ponds or lakes. So
abundant are lakes and ponds and
marshes in recently glaciated regions
and so rare elsewhere, that they CON
stltute one of the more easily recog-
nized characteristics of a glaciated re-
gion.
After the ice had melted. the mantle
Of drift which is left was sometimes so
disposed as to completely obIiterate
preglacial valleys More commonly il
filled preglacial valleys at certain
points only. In still other cases a val
ley was not filled completely at any
point, though partially at many In
this last case, the partial filings at
various points constituted dams above
which drainage was ponded. making
lakes. IL the dams were not high
enough to throw the drainage out OF
the valley, the lakes would have their
outlets over them. The drift dam be-
Ing unconsolidated would be auickl,
cut down by the out-fowing Water.
and the lake level lowered. When
the dam was removed or cut to its
base, the lake disappeared and drain
age followed its preglacial course.
. In case the valley was completely
filled, or completely filled at points.
the case was very different The drain
age ca the drift surface was estab-
lished with reference to the topogra,
ply which obtained when the ice de-
parted, and not with reference to the
preglacial valleys. Wherever the pre-
FolpgS Ntlt GOuDltLelY UlleQ,
IN postglacial drainage followed lines
which were altogether Independent of
them. When preglacial valleys were
filled by the drift in spots only. the
postglacial streams followed them
where they were not alied, only 10
ave them where the blocking occur
red In the former case the present
iraioage is through valleys which are
Ireglacial in some places, and post
glacial In others. Thus the drainage
changes effected by the drift after the
&c was gone. concerned both lakeF
md rivers. In this region there ar.
several illustrations Of these changes
The lake basins Of drift-covered re
lions are Of various types. Some
mem are altogether in drift. som
'artly in drift and partly ia rock. am
ONE wholly in rock. Basins in tn,
irift were likely 10 be developed when
yer heavy deposits surrounded tbb
mes. They are especially common =
ne depressions OF terminal moraine