Figure 20. Tephra set S about 7 km east of Mount St. Helens and 100 m above floor of Smith Creek valley. Thin lenses of grayish-brown ash (at tip of shovel) are the lowest beds of set S here; the overlying ash contains lenses of probable flowage origin. Layer Sw consists of multiple thin beds of brownish-gray ash containing white lapilli; it is overlain by crossbedded ash of probable flowage origin. Layer Ss here is a thin, brown ash that is barely visible under layer Sg. The reddish-brown upper part of layer So was weathered when that layer was exposed at the surface for more than a thousand years before being buried; pumice lapilli in the upper part of set S are soft enough to have been cut through during scraping of the outcrop. Shovel blade is about 25 cm long. Photograph taken in 1979.