The Salt Lake herald. [volume] (Salt Lake City [Utah]) 1870-1909, 1888-05-13
ANCIENT LAKE BONNEVILLE
Great Salt Lake the Largest Sur
vivOr of an Ancient Inland Sea.

The largest of the ancient lakes at
present known is Lake Bonneville, the
second in size has been named Lake
Lahontan. Lake Bonneville was sit
uated on the east border of the Great
Basin, principally in Utah, and ex-
tended from a few miles north of the
Utah-Idaho boundary 356 miles south
ward. 1t flooded all the valley of
Great Salt Lake, together with the Sc
vier and Esealante deserts in southern
Utah. It was 125 miles broad and 900
feet deep, where Great Salt Lake is now
situated. The site of the tample at
Salt Lake City was then submerged $50
feet.
Lake Bonneville overlooked north
ward and became tributary to snake
River, which flows into the Columbi
At various stages its waves and cur
rents formed terraces and gravel bars
on the mountain slopes which confined
it. These still remain as fresh and per-
feet as wnen they were formed, and are
in part the records from which the
gsologist has bten able to determine the
history of the ancient lake. We know
that it rose with many Quotations until
it had depth of about 900 feet, but did
not overflow. Then change of climate
caused it to contract its borders. and
possibly to become completely desic-
Gated. In the lower stages of this des-
location it was broken into separate
water bodies, which must have been
more or less saline.
Another great climatic change caused
the basin to be refilled to higher level
than before and to overflow. The
water found an outlet at the north end |
o; Cache Valley, Idaho, and, as we have
said. became tributary to Columbia. |
The lake continued to overflow until |
the waters had cut down their outlet 80 |
Ieet. During this period unless there
we're some peculiar conditions near the
point of discharge. the lake must have
been fresh. The discharge of the lake
vas finally stopped by a climatic
change which lowered its surface below
The bottom of the outlet, and again the
BASIN becameipart!yIfnot wholly desic
lated. This second low water period
las continued to the present day, and
3reat Salt and Sewer lakes are the rep
OF ancient Bonneville.
The largest of these representatives
VI the ancient sea is Great Salt Lake.
n 1850 it covered 1,750 and in 1869 2, 166
quare miles. Its maximum depth is
bout fifty feet and its mean depth ap-
fifteen feet. These recent
changes in area are due to small varia-
ions in climate, similar in character to
he changes which produced the great
expansions and contraotions of the lake
n ancient times. With change in vol
lime there is change in density; that Is,
tie strength of the brine increases with
decreased area, and decreases when the
axe expands. In 1850 its waters con-
aimed about twenty-five parts, by
Weight, of salire matter in solution to
90 parts of water. In 1869 the saline
natter had decreased to a little less
han Is and in 1873 to a little more
ban IA per cent. This change in
affinity was accompanied by increased
rea.
The waters of the ocean contain $40 &,
er cent, of total salts in solution.
Ireat Salt Lake therefore, in 1850, was
* times as saline as the ocean. Like E
be ocean, too, it holds many substances 7
i solution; the principle ones are COM {
ION salt, or sodium chloride, and So
ium sulphate; besides these there are
mall per centages of potassium, mag 1
esium, etc.
The influence of temperature on the {
of certain saline substances is
ell illustrated by this dead sea of {
tab. Its summer waters are clear and
but as cold weather comes i
q it becomes milky or opalescent, ow- S
lg to the precipitation of sodium sui i
hate in an extremely fine condition. 6
\ the depth of winter, when the tenn i
erature of the atmosphere above the
Ike falls far below freezing, an i'm S
tense quantity of sodium sulphate is c
recipitated and is thrown ashore by
le waves until thousands of tons &C.
emulate on the beach. Wnen the
rises, the salt thus precipi-
.ted Is again dissolved. This natural t
recess of fractional crYstallization pro-
uced by lowering of temperature, is
and should suggest to those
no are attempting to manufacture salt 4
! Utah practical method of treating |
ia natural brines in order to obtain {
ommon salt free from sodium sulphate.
AXE Sewer is also highly saline, and {
uripg the arid season sometimes evap-
rate to dryness.-Israel G. Russell in I
verLand Monthly.