Daily press and Dakotaian. [volume] (Yankton, Dakota Territory [S.D.]) 1875-1880, 1878-11-16

around Fort Buford, and many later strata
down to the most modern post-testiary de-
posts. We will at present give special at
tention to the old red sandstone Of Dakota,
la formation which seems older than the
Silurian red sandstone of which Hugh Mil.
Ter wrote, for ours has not yet shown the
least trace. of organic remains.
Its extent is unknown. Ito most eastern
exposure is at New Ulm, Minnesota, it up.
pears at the pipestone quarry near the
Dakota line, where its upper
laye rs contain the celebrated sheet
of Catlinite, or red pipestone. 1t then ap-
pears at various places along the Sioux,
from Dell Rapids down to the northwest
corner of lows, where there are q few acres
of this ancient bed left bare. At Rockport
and probably q few other places in the same
locality it crops out, and furnishes a valua-
bic building material. AT Sioux Falls, the
strata dip southwark six or eight degrees,
hence We suppose they run under all these
more southern prairies; but at the corner
of Iowa, several miles southeast, they dip
the other way about as much. This indi-
Gates that this ancient layer forms . bend
or Wrinkle upwards, in Dakota and Minneso-
lowest valleys; while it may extend for hun
at the surface any where else. If these
views are correct, it most have been heaved
up to its present elevation of twelve or thir-
teen hundred feet above the sea.
The question still arises, has it ever been
covered by any other rocks formed during
the infinitely long period between the azoic
and the cretaceous age? 1t has the appear
ance of being directly covered by the chalk
and the drift. If so, it was either upheaved
by wrinkles in the shrinking crust of the
earth soon after its formation, and remained
thus till this vicinity sunk and received the
cretaceous sea; or else it was long submerged
and received deposits Of rocks which have
been ages ago washed away or planned off by
the glaciers. The former superstition seems
most credible.
The thickness of this rock cannot now be
determined. Its upper surface is not def
nitely exposed, as it is SO worn and carried
away whenever exposed, and its bottom has
not yet been seen. Perhaps boring may some
time determine the question. The strata
that crop out at Sioux Falls have an aggre-
gate thickness Of 800 feet, but it may extend
for twice to five times that depth.
The origin or probablemode Of formation
Of this deposit is worthy ofattention. There
seem to be two distinct classes OF sandstone.
The first is a comented mass composed Of
grains of sand produced by the pulverizing
Of more ancient rocks, aud by asserting
them to uniform sizes by the sitting effects
Of waves and currents of water. In such
cases, the granules composing the rock are
ofgreat variety Of color and appearance, and
the rock has a gray or dingy look, contain
ing mixed samples from a thousand min
erals. Such is the appearance Of the gray
sand rock which caps a few hills in Nebras-
ka, and is brought to Yank!on for building
rock.
The second class is composed Of uniform
grains of slick or quartz, pure and free from
other kinds Of rock. This can hardly have
been created in the same way. Our quartzitt
is of the latter kind, its grains being fine lit
tie quartz crystals, nearly uniform in. size
~pervaded many of the rocks Of the azoic age
sandstone along the Mississippi: must have
of a deep and quiet sea, in which the Slice
Gus grains crystallized and fell to the bottom
like snow in the air. or sugar in a syruI
cask. Dana in his older works asserts thai
the amount of such chemically formed rocl
must be small; but later writer's consider il
very extensive. They include not only
sandstone, but Limestone, gypsum, and
many rocks since me~tanorphosed BY
heat, pressure and. time, until their original
texture can not be perceived. This quartzite
has been thus metamorphosed by The ce-
menting of its grains into one t1inty mass,
except in a few spots where it may now be
found slightly soliditied, and where one may
scrape it up in handfuls of red sand.
The supposed process of its formation may
be briefly given thus in the age when the
earth had but a thin heated crust Of igneous
rock, chiefly composed of silica, as chemical
analysis to-day proves, all the sulphur, car.
bon and chlorine Of our planet must, like
the water and other volatile substances,
have been existing onlyein the surrounding
atmosphere in their gaseous forms. The
process of cooling by constant radiation into
space. at last brought a time when the
watery vapors could condense into rain and
fall upon the fiery siliceous rocks of the
earth's crust. Such rainy torrents. would be
intensely charged with %sulphuric acid, car
bonic acid, chlorine gas, and other powerful
chemical agents, capable Of so decomposing
the rocks that the first boiling ocean waters
that could rest upon them would be satura-
ted solutions of slick, lime, alumina, soda,
and other mineral bases. In later ages Of
cooling, these oceans of mineral waters
would precipitate their surplus matter in
crystallized grains or fine powder. Very
likely the slick would %precipitate first of all,
and thus create the enormous beds of pure
quartz which are found in the oldest strata
in all parts Of the world; while the car
Donate Of lime or marble, the sulphate Of
lime or gypsum, the aluminous rocks or
clays and states, and many other mineralp,
would follow in due time.
At Sioux Falls the quartzite displays
many interesting surface features. There
are large surfaces smoothed, striated and
rasped down by the power ofthe glacier and
its underlying stones and gravel. There are
areas of dry rock showing wonderful places
grooved and gouged into fantastic shapes by
the action Of the great river which must for
ages have run and leaped} over the whole
bed of the valley, where now the Sioux
flows as comparatively a gentle brook.
There the finty old rock. so hard that ito