30 TOPOGRAPHIC DEVELOPMENT OF KLAMATH MOUNTAINS, [bull. 196. 
to Humboldt Bay it appears that next to the coastal plain, ranging 
from 10 to about 200 feet above the sea, the 1,000-foot terrace is the 
most general, and that its occurrence at places all along the coast is 
evidence not only of a general long halt in the uplifting at that level, 
but also that the uplift since then has been approximately uniform. 
It is probable that much of the 1,000-foot terrace has been removed 
from its western edge by erosion. 
MARINE DEPOSITS BORDERING KLAMATH PENEPLAIN. 
AT CAPE BLANCO, OREGON. 
Neocene deposits have long been known en the coast of Oregon and 
northern California, 1 but in only a few cases have they been described 
and their fossils studied. They are made of the sediments washed 
from the land in developing the Klamath peneplain, which they bor- 
der, and their age is a matter of importance in determining that of 
the peneplain. 
Along the coast of Oregon from the mouth of the Columbia to 
Yaquina Bay 2 these deposits are almost continuous. They are well 
exposed on the Columbia River near and opposite Astoria, along the 
beaches farther south, near the mouth of the Nehalem, at Tillamook 
Bay, and along the beach, bay, and river of Yaquina. Their next 
known occurrence is at Coos Bay, where the Empire beds, of Miocene 
age, are well exposed and have been carefully studied, both strati! 
graphically 3 and paleontologically. On this account they serve as a 
basis for comparison. South of the Coos Bay quadrangle, which 
extends to the forty-third parallel, Neocene strata occur between 
Floras Lake and Blacklock Point, and from Cape Blanco to the 
mouth of Elk River. Both of these localities are in the Port Orford 
quadrangle and will be more fully described in the folio. 
On the north side of Blacklock Point there is a fine exposure of 
about 100 feet of soft, yellowish sandstone unconformably overlying 
gray sandstones of Cretaceous age. Near the base there are numer- 
ous fossils which Dr. Dall recognizes as Miocene of the Empire beds 
horizon. 
At Cape Blanco, shown in the distance of PL IX, looking north, 
there is a sheer cliff of 200 feet of soft sandstones rich in fossils of 
the Empire beds. To the southward the Cape Blanco beds are 
exposed along the coast for 3 miles, dipping gently in the same direc- ! 
tion to the mouth of Eel River, where they pass beneath the beach. 
They are full of fossils throughout, and large enough collections were 
made to leave no question as to their being Miocene of the Empire 
i Bull. U. S. Geol. Survey No. 84, 1892, pp. 200-217, 223-227. 
2 Seventeenth Ann. Rept. U. S. Geol. Survey, Pt. 1, 1896, p. 29. 
3 Coos Bay coal field: Nineteenth Ann. Rept. U. S. Geol. Survey, Part 111,1898, p. 319, and 
PI. XLVII1. The formation is described also in the Coos Bay folio, No. 73. See also Dall's paper 
in Eighteenth Ann. Rept., Pt. II. 
