|
|
|
Lake Salinas
by
E. B. Preston
|
|
|
|
|
|
1890, "Lake Salinas, Los Angeles County",
by E. B. Preston, Assistant in the Field, California State Mining Bureau, Report
X, (p. 281), Source: California Geological Survey Library
|
|
|
Full Transcription:
"Lake Salinas
Within the town site of Redondo Beach is a small salt-water lake, about three hundred
yards from the ocean, and about five feet above the high-water mark, that does not
receive its water supply from the ocean, having an entirely different combination
of salts, and has about it and its immediate surrounding features that make it of
interest to the geologist and chemist.
The lake is about a half a mile long, and from four to six feet deep. At the south
end is a large shallow basin connected by movable gates with the main lake, which
is used for evaporating the water by the heat of the sun. The banks are low, gradually
sloping up; a sand dune intervenes between the ocean and the lake; the bottom of
the lake is a bed of clay. Around this lake on both sides, about thirty wells have
been bored to an average depth of twelve feet into the clay that forms the bottom
of the lake, and these all yield a good, soft drinking water. Between these sweet
water wells next to the ocean, and the ocean itself, near the top of the dune a
well has been sunk to a depth of twenty-six feet, which has passed through the clay
for a distance of ten feet. The water obtained in this well is claimed as having
medicinal qualities; it certainly tastes bad, if that is an criterion of its medicinal
value.
The lake water is a much stronger solution of salts than the water from the open
ocean, containing a very much greater proportion of chloride of magnesia; but the
statement as made by the parties on the spot to the writer, that the water was ten
times as saturated as the sea water, is evidently erroneous, as such a solution
would pass the point of saturation. How to account for the presence of these different
qualities of water in their relative positions, is not plainly to be seen. The salt
water could be accounted for in several ways, as there are beds of saliferous shales
and sandstones in the neighborhood; also, there are magnesian rocks on the flanks
of the mountains surrounding the plain; but the fresh water in the wells surrounding
the lake interferes, from the fact that these wells, terminating in the clay, compel
the assumption that the water in them is drainage water from the near vicinity.
To solve the question satisfactorily would require a closer investigation into the
position of the different strata than the limited time at disposal afforded.
South of the town of Redondo Beach about three miles, the bluffs facing the ocean
are composed largely of sandstones and shales, with a large bed of diatomaceous
earth resting thereon; underlying these and running out to sea are beds of bituminous
sandstones, showing natural bitumen in places. These continue in a southwesterly
course out to sea as a reef for a distance of two and one half miles, at which point
oil is seen coming to the top of the water in considerable quantities."
|
|
|
|
|
|
|
|
|