148 B. WILLIS—DRIFT PHENOMENA OF PUGET SOUND. 
Their distinguishing characteristics are: Their position beneath the 
‘other formations; their coarse heterogeneous composition, including 
sands, numerous big pebbles, and boulders; their color, which is fre- 
quently orange brown, and the decomposition of granite pebbles, which, 
although not general, is of such repeated occurrence as to mark the age 
of the formation in contrast to the fresh Vashon drift. 
In the section exposed in the north bank of Carbon river these gravels 
are conspicuous on account of their color. They form the lower part of 
the bluff between 500 and 560 feet (150 and 170 meters) above sea. They 
are interbedded with orange-colored sands and exhibit much variety of 
texture and bedding in adjacent sections. 
At Orting they are well exposed on the east bank of Carbon river, where 
they present a very compact mass of heterogeneous materials. ‘They are 
now to be seen from 200 to 340 feet (60 to 100 meters) above sea, between 
the river bank and the overlying Puyallup sands. Their characteristic 
color is less pronounced in this and other occurrences along the Puyallup 
valley. On the west side of the valley, 4 to 5 miles (6 to 8 kilometers) 
north of Orting, these gravels frequently form vertical or overhanging 
steeps. 
_ Along the eastern side of the Puyallup-Duwamish valley there are ex- 
posures of stratified sands and gravels, two of which, one 4 miles (6 kilo- 
meters) and another 9 miles (14 kilometers) north of Orting, are described 
in the accompanying detailed sections. The former of these, lying be- 
tween 100 and 170 feet (80 and 52 meters) above sea, exhibits an inter- 
esting structure. The distinctly stratified beds of gravel and sand dip 
from both ends of the exposure toward the center. They are traversed by 
numerous small normal faults, also inclined from either end toward the 
middle, which is thus additionally depressed. The structure is that 
which might probably be produced by slow wasting of a buried ice-mass, 
and as such it appears to indicate the presence of stagnant ice during the 
deposition of these particular beds. These strata are in part readily corre- 
lated with the Orting gravels, but their upper portion may correspond 
with the lower beds of the Puyallup sands. 
Evidences of mild climate—The deep orange color of the Orting gravels 
is due to the hydrated oxide of iron with which they are in part cemented. 
The ferruginous coating of sand grains and the stain on pebbles is so uni- 
formly diffused in the mass that the accumulation of iron oxide appears 
to have been a condition closely connected with original deposition. It 
thus differs from the superficial rusty aspect of those blue clays which 
oxidize and turn brown on exposure to the weather. The blue clays are 
usually till spread beneath ice or sediments derived from till and depos- 
ited in icy waters. ‘The iron which they contain was prevented from 
