Daily press and Dakotaian. [volume] (Yankton, Dakota Territory [S.D.]) 1875-1880, 1878-11-16
GEOLOGY OF DAKOTA.
A Paper, Mainly Devoted to the Sioux
Falls Quartzite, Read before the
Yankton Scientific Association.
BY A. W. BARBER.

BY A. w. ARB
In looking over this territory and examin
ing here and there local facts in the geolog,
of Dakota: we find a rich and varied field O
research. 1t is true there Is much monoto,
nous prairie, where all the rock. beds arc
deeply buried in drift, but all along thu
Missouri and the larger tributaries, and il
the bluffy and billy regions. much is found
OF deep interest to the observer. In south
eastern Dakota, the three most conspicuous
and general features are; first and lowest,
the cretaceous beds, forming the chalk rocks,
and clays; second, the drift or debris of sand,
clay, gravel and boulders, left by glaciers ;
third, the bluff deposit, a fine yellow soil.
everything the others in part of the country
only. These are we'll described in the able
paper contributed last week by Mrs. Pawlyn.
will add that this bluff deposit extends all
through western Iowa, reaching a depth of
two hundred feet in some places. 1t is every
where remarkably uniform in composition,
containing silica. 50 per cent, carbonate Of
lime 10 per cent, oxyd, of iron 4 per cent.
and small proportions Of %alumina, magne-
SUM, &C.,
The soft cretaceous layers have been fur
rowed and worn, and covered by the drift
and bluff deposits. Below all thesein most
parts of the world lie the m%ultitudinous
leaves of the geological book from the reptil-
ian age downward through the coal. bearing
strata, the limestones filled with remains Of
fishes and mollusks and the old Potsdam
sandstone, down to the igneous rock which
first formed the crust of the globe as it
cooled from the molten state. Yet here in
Dakota as We pass from the chalkblu& of
the lower Sioux river over a few miles of
prairie, we suddenly find ourselves, at
Sioux Falls, walking upon the azoic rocks
of the earliest ages of the world. The Sioux
quartzite, or finty red sandstone, is held to
be a deposit Of the azoic or ~lifeless age,
when all pervading heat and a poisonous
atmosphere prevented any living plant or
animal from %inhabiting the globe. Where
are all the later strata that should intervene
between this ancient bedrock and the mod
ern chalk? Why. are they not here as we'll
as elsewhere?
The areas OF the earth's surface where azoic
rocks form the surface layers are few and
Of limited extent. They occur from three
first, from having never been over
flowed by seas, as for instance, the northern
shore of Lake Superior, and hence not hav-
ing been buried by later deposits second,
those submerged and again upheaved, from
which the deposited beds have been washed
away or torn off by aqueous or glacial phe-
nomena; third, those which we're deeply
buried, but afterwards thrust up through the
covering masses, by forces Of volcanic
character, as in the Black Hills and Rocky
Dakota presents a wider range of geolog-
ical epochs than most of the states of the
Mississippi valley, having the igneous rock,
the trap and granite of the Black Hills, the
quartzite of the Sioux region, the volcanic
lava-beds Of the extreme northwest, as