Geological Survey Professional Paper 604 On Batholiths and Volcanoes—Intrusion and Eruption of Late Cenozoic Magmas in the Glacier Peak Area, North Cascades, Washington

PETROLOGY OF THE GLACIER PEAK LAVAS
(continued)

HOT SPRINGS

There are three springs on the flanks of Glacier Peak (see table 5). Gamma Hot Springs on Gamma Creek and Kennedy Hot Spring on the White Chuck River are shown on plate 1; Sulphur Hot Springs on Sulphur Creek, three-fourth of a mile from the Suiattle River road, can be located on the Downey Mountain topographic 7-1/2-minute quadrangle map.

TABLE 5.—Chemical analysis of hot springs in the Glacier Peak area

[Sulphur Hot Springs water analyzed by R. Schoen; others by G. E. Roberson, Nd, not determined. Also not determined are: Al, Fe, Mn, Ph, PO₄, H₂S. Analyses in parts per million unless otherwise specified]

The Sulphur Hot Springs are highly odiferous and bubble forth in a shallow murky pool. Gamma Hot Springs, the hottest of the three (table 5), issue from several cracks in the bedrock of the streambed. Kennedy Hot Spring (1963) has been developed as a wilderness spa and now flows into a log tub coated with tufa, iron oxides, and slime. Several cold but odiferous seeps frequented by game are scattered on the slopes behind Kennedy Hot Spring, and one a few yards upstream has covered a few square yards of bedrock with tufa.

As a group the waters of the Springs (table 5) are similar to those of other thermal springs associated with volcanic rocks, and they are classified as sodium chloride bicarbonate waters (White and others, 1963, table 18, p. F42). Assuming they have the same magmatic source, their differences in composition could be ascribed to ground-water dilution, especially in the case of Sulphur Hot Springs.