Sunbury American. [volume] (Sunbury, Pa.) 1848-1879, 1850-06-08


0 rock strata.
Thus, below the entrance TO Lake Pepin
the loucr sandstone spoken of, constitute
about $40 feet Of the bluff hills, and the lowe
mdgneSian limestone 150 feet more, immedi
ately over it, AT the great bend of that Lake
on the Norih-eas, side, this lower magnetism
limestone may be seen forming perpend
cnlar wall of nearly 200 feet, the total height
above the Lake being 4o9 feet. This is the
spot celebrated in Dakota legends as the
Maiden's rock, or Cape de Sioux. AT the
head OF the Lake, on the West side, the same
magnetism limestone forms about 160 feet OF
the upper portion of La Grange Mountain, at
little below Red Wing, or Reminicha Viii
lage. lis base for upwards OF ITO feet is of
the lower sandstone. Thirteen miles below
the ST Croix, this sandstone can no longer be
seen, and The lower magnetism limestone
extends from the level Of the Mississippi, TO
the height of 240 feet. But Immediately be-
low the mouth of the St. Croix only low
lodges of The same limestone rock appear,
the bluffs not rising higher than 70 feet and
at the mouth it sinks still lower down.
Still ascending the stream, the strata takes
local rise, or undulaiion, so that three or
four miles above the mouth of the St. Croix,
the lower sandstone again emer.es from be-
meath The water, and is seen for 10 or fifteen
| feet above low water mark. 1t very soon
! sinks, however, for at Red Rock, on the east
bank, six or eight miles from ST. Paul. there
are only low ledges of the lower magnesian
limestone, twelve feet thick and not far be-
yond this point, ii disappears entirely from
the surface, so that before reaching St. Paul,
it is replaced by the upper phitc sandstone
that al Prairie du Chen was noted, (No. 81
as lying over it.
This sandstone constitutes the base of the
bluffs at St. Paul and St. Peters, and the
lower 10 feet of the chute at the Falls of ST.
Anthony.
Between ST. Paul and the Fountain Cave,
two miles above the town, :he different rock
strata dip down, going up stream, at the of
% to 80 feet per mile. At the last named
point, still going up stream, there is another
rise in the strata, al the rate of about ten feet
to the mile
Next above this upper sandstone, from Red
Rock TO ST. Anthony Falls, there is a forma-
ton OF limestone, disposed of in thin regular
layers. This is called shell or fossiiferous
limestone The lower portion is the purcst
limestone of the Mississippi region of Mime
sofa, containing near sirty.fue per cent. of
carbonate Of lime, and thirteen per cent. only
OF carbonate Of magnesia, and will without
doubt afford by burning better lime than any
OF the calcareous rocks North of Lake Pepn
II contains % parts more lime, and IS parts
less magnesia, than The shell lime stone
which forms about eleven feet o! the upper
portion of the same formation of fossIferous
limestone. The whole thickness of the shell
limestone, upper and lower beds, is about
thirty feet.
The lotger magnetism limestone extends M
The rivers Cannon and VermilIion, as far as
explored. The lower sandstone formation
aud the magnetism limestone compose The
bluffs of Hookah or Root, Miniskah, Wazi
Oju, and of the St. Peters rivers.
METALLIC ORES OF MINNESOTA
The rocks of Minnesota, as above described
considered in reference TO their mineral con-
tents, strongly indicate the presence in the
territory, of rich deposits of the ores of lead
and copper.
DR.. Owens says the lower magnetism lime
stone has MANY characteristics which indi.
cate metalliierous rock. 1t occurs in thick
and solid walls, massive and durable it is
traversed by renls and assures of determinaie
course, Of which the walls have little dspo-
stion 10 give way; is intersected by spars
crystalizations, and vein stones, such as usu-
ally accompany metallic ores. Along certain
parts of lis range, il bears evident marks of
local disturbances, the sign of an ad diacenl
axis of dislocation, and il has many points Of
resemblance 10 The upper Magnetism lime
stone, which is The lead and copper bearing
rock of Iowa and Wisconsin
The lower magnetism limestone may in
one respect, DR.. Owen thinks, che considered
more favoraby situated than the upper, as a
mineral bearing rock. 1t is an established
fact that in Geology, all other things being
equal, that The lower or older rock is the
morely likely it is 10 be metalliferous, because
nearer the sonrces from whence experience
indicates thai metallic materials fud their
way into its recesses; in other words, be-
cause it is in closer proximity to granite and
crystalline rocks and It has been shown that
the lower magaesian limestone is merely Sc
parated from the crystalline and igneous
rocks, by the loWsr sandstone only"
In corroborauon of these geological infer;
ences DR.. Owens cites several discoveries of
lead ore in the rock formation in question
one near the Mississippi, 10 or 10 miles above
the mouth of Turkey river several north of
the Wisconsin river near the mouth of the
Kickapoo; at all of which considerable lead
ore has been obtained. On the Upper Iowa
river, along the southern boundary of Mime