The silver star., 1897-04-15
Geology of tn. Yellowstone Park.

The Geological Survey of the Yellow
stone Park was begun by the national
government in 1888. Seven years of
field work and as many more of Of
flee and laboratory study have been
devoted to this subject by specialists of
the United States Geological Survey.
and now the publications are approach
Ing completion. md the first work, the
Geological Folio of the Park. has lust
been issued.
The Folio consists of six pages OF de-
scriptive text; three pages of illustra-
tions. four topographic sheets. (scale
1.125.OOO), and four sheets delineatinv
the areal geology Of the region.
The general descriptive text giving
a succinct narrative of the geological
history and development Of the park
country from the time of the earliest
continental land surfaces up to and
Including the hydrO-thermal phenom-
ena as seen to-day was written by Ar
mold Hague. geologist In charge.
1t IL followed by an account of the
seiimentary rocks from the earliest
Cambrinn deposits to the TertInry con
glomerates by Walter Harvey Weed.
and n detailed petrograplical descrip-
tion OF the igneOus rocks by Joseph Id
dings.
Ah' vi country covered Nv ttln
Yellowstone National Park Folio lies
between parallels A. and AZ degrees
north latitude. and meridians 40 and
III. 1t IN situated In the extreme
northwest corner Of Wyoming. BY far
the greater pnrt OF the park IL incIud-
ed within the nrea Of the four atlns
sheets. but narrow strip lies to the
northwnrd In Montana. nnd still nnr-
rover strip extends west ward both
into Idaho and Montana.
In the organic net establishing tho
park. Congress declared TINT the reser.
wilton wns dedicated and set apart M
a. public park ana pleasure ground for
the benefit and enjoyment OF the peo.
PIE Owing to the marvellous display
OF geysers and hot springs. and such
reIhnrkable physical features as the
Grnnd canon and Yellowstone like.
this folio possesses more than ordinary
Interest to every studious man.
The Oldest rocks Of this region arc
GRANTEES. gneiss and schists regarded
as OF Archcan age. They occur In Mi
the mountain upliftS that encircIe tho
pnrk. but nrc unknown In the ccntrnl
portion. Around these ancient contI-
nentnl land masses there wns deposit-
ed cOnfOrmable series OF snntistoi,es.
llmestOnes and shnles. extending from
the time Of the middle Cnmbrinn, tho
lowest beds exposed through the upper
Cnmbrinn. sllurian. Dev0ninn. Carbon
ferrous. TrlnS. Jurassic and Crctaceoun.
Including the Laramie santistones.
Nearly nll these great divisions OF
PnleOxoic and MesOxOic times nre char.
ncterixed by typical fossil fauna.
With the close Of the deposition Of the
Laramie sandstone the c0nformable
series Of sediments cnme to nm end.
The entire region was elevated above
the sea with pllcation md folding OF
strata. This primary geographic uplift
which blocked out the main ranges Of
the northern Rocky Mountains has
been designated as the Post Laramie
movement.
Tertiary watcr laid rocks occupy only
small nrens In the pnrk, the greater
part OF the region being covered by
extensive flows Of lava. A heavy mass
Of coarse c0ngl0merate has been re-
ferred to the Eocene; and an Obscure
exposure Of Pilocene conRlomerate and