Polk County observer. (Monmouth, Polk County, Or.) 1888-1927, 1911-01-31
POLK ROAD MATERIAL |
SCIENTIFIC EXAMINATION MADE
OF ROCK DEPOSITS HERE.
Experts From Oregon Agricultural
College Give Their Opinions on
Local Supply.

The subject of good roads is one
that especially appeals to the out-of-
town resident just at this time. One
reason for this is the proposed meas
ures on the subject before the State
Legislature; another is the necessity of
good roaods is more apparent at this
time of the year than at any other.
Hence it is that a recent bulletin on
Road Materials of the Willamette
Valley" issued by the Department of
Geology and Mining Engineering, of
Oregon Agricultural College, will re-
ceive more than usual consideration
Polk County was included in the
survey, and the results of the scientific
examination made of the several de-
posits of rock in this region are shown
in the following excerpts.
This bulletin is not intended to be a
scientific treatise in geology, but is
written expressly for the road build
err using only the principles of geology
in so far as they can be applied to the
intelligent selection and handling of
road materials:
Polk County Rock.
POLK County is not as well supplied
with available outcrops of road mate
rial as are some of the other counties
in the valley. However, a number of
good quarries have been opened and a
number of outcrops located which will
be of great service to the road builder.
In the vicinity west from Dallas the
hills contain some outcrops of basalt
of excellent quality. The two quarries
from which the rock for the city has
been obtained, one three miles west
and the other two miles west and one
mile north, show very fine grained,
black, dense, varieties of basalt, which
are as good in quality as any to be-
found inthe valley. Four and one-halfI
miles north and one mile west of Dali
las is another excellent basalt quarry.
The mass of rock is profusely fissured
similar to that found in the Ewald
quarry near Salem, and because of the
assures is more easily quarried than it |
would be otherwise.
Limestone Deposits.
"Four miles west of Dallas are To-
Gated some limestone quarries which
were recently purchased by the Oswe
go Cement Company of Portland This |
rock seems to be very popular in this
section as a road material, largely on
account of the fact that it is easily
quarried and crushed and works down
quickly into a good road without being |
rolled. From this standpoint it GER
tainly is a good rock for road material
but cannot be recommended for use
alone for building the best macadam
roads. Under heavy traffic the surface
idly and will need constant repair, as
the rock is not hard enough to suffi-
ciently Withstand the abrasion of
heavy traffic. This rock used as
binder for harder trap rock would
make excellent macadam roads, which
would give the best of satisfaction.
Just west of the town of Falls City is
a quarry in coarse grained diabase.
This is a tough, hard rock and gives
good tests as a road material. Four
miles southeast of Falls City is a quar-
ry. the rock being the same as that of
the Falls City quarry. In the vicinity
Of Monmouth some basalt quarries
could probably be opened up by maxi
ng careful search, as is evidenced by
he fact that basalt boulders are found
;trewn over the hillsides in this vi
Unity.
Gravel as Substitute.
Polk County has large areas which
apparently have no available road ma I
erial. On this account it will be nee
ssary to depend largely upon the Will |
annette River gravels for economic
materials. BY crushing and transport
ng by rail these gravels can be readily
distributed to nearly all parts of the
ounty"
THE field observations which form
he basis of this report were made
" II. M. Parks, assisted by S. w.
'rench and II. Z. Cooke, and was COM
leted during the summer vacation
months of July, August and September
f 1910. The area covered I'm this |
econnaissance includes only the more $
ensely populated portion of the Will J
annette Valley. which is in general the \
lain floor of the valley, including only {
he first rim of foothills as a bound {
ry.
1T has often been stated that Ore I
on has more good road material than
ny other state. a statement which is J
oubtless true. The fact still remains, Z
owever. that the road builders of our '
tate are usually not sufficiently well $
ersed in the principles of geology to :
e able to distinguish excellent mate
ial from that of medium quality, nor ]
he material Of medium quality from
he poor material. 1t is also a fact q
hat the road builder will often trans '
Ort his material from long distances
{ an extra cost when as good or bet G
sr material is close at hand"