diller] EARLIER VALLEYS. 51 
rise; that of the East Fork of the Coquille at Lairds has an altitude 
of over 2,000 feet and affords a fine view of the adjacent edges of the 
Klamath peneplain. 
EARLIER VALLEYS OF SIXES AND ELK RIVERS. 
South of the Coquille the rocks of the irregular complex below the 
Eocene come to the surface, giving rise to greater irregularity in the 
topographic features. 
( )n Sixes River the earlier valley was well developed not only along 
the main stream but also along the principal forks. From a sharp crest 
northeast of the trail crossing from Sixes to the mouth of Edson Creek 
a fine view up the old valley of the Sixes may be obtained at an 
altitude of about a thousand feet. Farther west, a little below this 
level, on both sides of the river there is an extensive terrace capped 
by the highest marine sands noted in the region. The earlier valley 
ends in this terrace, suggesting that the two are contemporaneous, 
but it seems more probable, from facts considered elsewhere, that the 
terrace is much younger than the "earlier valley." 
Farther up the Sixes the early valley bottom near Elephant Rock 
has an altitude of 1,200 feet. Looking toward Eckley from Elephant 
Rock one of the finest views of this old valley may be obtained. 
Opposite Mount Avery it has a depth of nearly a thousand feet below 
the level of the peneplain. 
The broader valley about Eckley is due to the basin of softer 
(Jocene sediments. On the South Fork of the Sixes, between Mount 
Butler and Mount Avery, the old valley at an altitude of 2,000 feet is 
shallow, being but a few hundred feet below the general level of the 
peneplain. Here the abrupt change of slope to the canyon of the late 
valley, 1,500 feet deep, is conspicuous. Farther east, about the head- 
waters of this stream, the plain of the early valley is much wider, with 
gentle slopes to the level of the peneplain. 
On Elk River a few miles south of the Sixes the conditions are 
much the same, but the early valley is not so well preserved, chiefly 
on account of the large number of landslides, due in part, apparently, 
to the killing of the timber by forest fires. All the timber for many 
square miles has been killed. 
. EARLIER VALLEY OF ROGUE RIVER. 
From the south of Bald Brushy Mountain and First Prairie Moun- 
tain a good view can be obtained of the earlier valley of Rogue River. 
On the south bank of the river, a few miles above the mouth of Silver 
Creek, is a flat-topped hill, a portion of the old valley bottom, having 
an estimated elevation of nearly 2,000 feet. On both sides the valley 
lias a gentle slope rising from that elevation and marking the general 
outline of the earlier valley, in strong contrast with the canyon below. 
The earlier valley of Rogue River, although larger, is less sharply 
marked than that of the Sixes. 
