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

or at least the finer parts, were
handled by the waves of the shallow
waters, for they were AIT first shallow.
and assorted and re-distributed Thus
the residuary products on the sub
merged surface, were one source of
sediments, From the shores also. SO
long as land areas remained, the
waves derived sediments. These were
composed in part of the weathered
products of the rock, and in part of
the undecomposed rock against which
the waves beat. after the loose ma
teriais had been worn away. These
sediments derived from the shore were
shifted, and finally mingled with those
derived from the submerged surface.
so long as any part of the older land
remained above the water its streams
brought sediments to the sea. These
also were shifted by the waves and
shore currents, and finally deposited
with the others on the eroded surface
of the quartzite. Thus sediments de-
rived in various ways, but inherently
essentially similar, entered into the
new formation. The first material to
be deposited on the surface OF the
quartzite as 1t was submerged, was
the coarsest part of the sediment. OF
the sediment derived by the waves
from the coasts, and brought down to
the sea by rivers, the coarsest would
at each stage be left nearest the shore,
waile the finer was carried progress
lively farther and farther from Il.
Thus at each stage the sand was de-
posted farther from the shore than
the gravel, and the mud farther than
tie sand. where the water was SO deep
that the bottom was subject to little
agitation by waves. The theoretical
distribution of sediments about an
island as IL was depressed, Is illustrat-
ed by the following diagrams, Figs. Z
and 8. IL will be seen that the surface
of the quartzite is Immediately over
lain by conglomerate, but that the
conglomerate near its top is younger
than that near its base"
In conformity with this natural
distribution OF sediments, the basal
beds of the qotsdam formation are
often conglomeratic. Gig. 3D. This
may oftenest be seen near the quartz
lite ridges, for here only is the base OF
thd formation commonly exposed.
The pebbles and larger masses of the
conglomerate are quartzite, like that
OF the adjacent beds, and demonstrate
the source of at least some of the ma
terial of the younger formation. That
the pebbles and powders are OF
quartzite is significant, for II shows
that the older formation had been
changed from sandstone to quartzite
before the deposition of the Potsdam
sediments. The sand associated with
the pebbles may well have come from
the breaking up of the quartzlte,
though some of It may have been
washed in from other sources by the
waers in which tho deposition took
place. The basal conglomerate may
be seen at many places, but nowhere
about DEVILS lake is II go well exposed
as at Parfrey's glen, where the round
ed stones Of which IL Is composed vary
from pebbles, the size OF a pea, TO
powders more than three feet in d.
ameter. Other localities where the
conglomerate may be seen to adyan-
tage are Forwards glen, the east bluff
at Devils lake just above the Clin
house, and al the upper narrows OF
the Baraboo, above Ablemans"
The main quartzite range three