Page 253 - 1915, Springs of CA.

CARBONATED SPRINGS. 235

the river. It issues from a crevice in massive granitic rock, 15 feet
above the level of the meadow, and like the other springs it is strongly
carbonated and has deeply iron stained its channel, but its yield is
very small, being perhaps one-eighth of a gallon a minute. There is
another seeping flow, of little importance, 50 yards northeast of
Potter Spring, at the edge of the meadow.
For some distance south of this meadow the river flows northward
toward it through a small, rocky gorge, in which, 100 yards above
Potter Spring, there is a pothole in the massive granitic rock. A
small amount of carbonated water apparently rises in this basin from
a crevice beneath the rounded bowlder that it still contains, for the
water in the pothole is rendered turbid by iron in suspension.
The distinctly ferruginous character of the water at Eubicon
Springs is noteworthy in connection with the fact that they are sur-
rounded for several miles by the massive iron-bearing granitic rock
that is classed as a granodiorite.1 The slopes on each side of the
river are largely devoid of soil and present an unusually good example
of the granitic slopes of the Sierra.

WENTWOBTH SPRINGS (ELDORADO 2).
Wentworth Springs are 5 miles in a direct line (8 miles by road)
westward from Rubicon Springs in a small area of open land near
Gerle Creek. The property was at one time claimed by a settler,
and in 1909 a house still stood in the flat, but for several years the
place has been only a small campers' resort. It has been visited
mainly by people from Auburn and other towns to the west.
At this locality two groups of small springs issue along a small
wash that is tributary to Gerle Creek. At the lower group six natural
basins in an outcrop of schistose rock receive seeping flows of car-
bonated water from crevices in the rock. Two of the basins -those
chiefly used have been protected by a fence railing and a board
roof. The water in one of them is distinctly sulphureted, and all
apparently contain considerable amounts but different proportions
of salts in solution, as they differ noticeably from each other in taste.
Chemical examination of water from the principal spring has shown
the presence of abundant sodium, calcium, and magnesium and
chloride and carbonate, as well as notable amounts of carbon dioxide
and hydrogen sulphide. About 250 to 300 yards eastward, up the
creek, eight other carbonated seepages discharge to small basins,
in two of which sections of tile pipe have been sunk so as to form
drinking pools. All of the springs of this group deposit considerable
iron and noticeable amounts of lime carbonate. Like the lower
springs they issue from schistose rock that is the result of contact
i Lindgren, Waldemar, U. S. Geol. Survey Geol. Atlas, Truckee folio (No. 39), 1897.