CRETACEOUS BEDS, OF ROGUE RIVER, VADERYV., “AS 7. 
follows the upper portion of Anderson Creek to its head; from 
Talent the line between the slates on the west, and the basalt on 
the east, runs in a northerly direction. _ 
Each region and each series has its own distinguishing char- 
acteristics. The rocks of the granite series are made up of mas- 
sive granites and of folded and contorted schists. No attempt 
was made to separate these in working out the areal geology. The 
peaks and ridges of this area are high and rugged, and the canyons 
are deep and generally heavily timbered with spruce and pine. 
The slates, which are no doubt a northward continuation of 
the auriferous slates of California, portions of which they closely 
resemble, are variable in character. In some places they are 
dark, fine grained and argillaceous; in other places they are 
micaceous, talcose or shaley with large masses of quartzite. 
Where they are auriferous they often contain numerous small 
and irregular veins of quartz. The mountains of the slate area 
are less rugged, often low and less heavily timbered than those 
of the granite area. 
The area of basaltic rocks is also well characterized by regu- 
lar and rolling hills which are generally not deeply eroded, and 
in which the rocks seem to be more uniform. These basaltic 
hills form the western edge of the Cascade range at this point. 
For the most part they consist of old basalts, andesites and other 
basic eruptives.* 
Upon each of these series of rocks the Cretaceous strata 
rest with equal distinctness, and with equal absence of metamor- 
phism, or alteration, other than what would be expected from 
weathering. The only case of alteration that was observed in 
these rocks is in the immediate vicinity of dikes of limited 
extent, which have made their way through the strata at various 
places, often without disturbing the regular position of the beds. 
In such cases the alteration is confined to a few feet or yards on 
each side of the intruding mass. As far as is known the dikes 
occur mostly along the line of junction between the granite and 
the basalt. 
*Seventh An. Rep. U. S. Geol. Sur., p. 98. 
