The Sumpter miner. [volume] (Sumpter, Or.) 1899-1905, 1902-11-05

Mount Maxama AZ q drainage center !
quite equal ~ that Of Mount Shasts
but its slopes on the rim Of Crater lake
ranging from 100 to i5o, are scarcely a
great IN those Of Mount Shasta at
corresponding elevation. On the othe
hand, the canyons Of Sun and SAM
creeks on Mount Mazama are more pro
found and have been much more deepl
glaciated than any Of those on Noun
Shasta. Itthercfore appears reasonable
10 suppose that Mount Maxama had q,
altitude ut least M great, and possibl!
greater than that Of Mount Shast,
/ U+,3sO feet).
There were eruptive flows Of lava from
Mount Mazama, and also great explo
sivc eruptions Of pumice, the greatest
eruptions, perhaps, Of the Cascade
range, and then cane the revolution
which removed the large cone and the
upper 5000 feet Of Mount Mazan,a, and
gave rise 10 the caldera,
The evidence seems to be against the
view that this destruction OF the noun.
tain was by an explosion which blew
the upper part of and out. A large
number (l'iS) Of soundings made under
the direction Of Major Dutton, U. :. A.,
show that the inferred bottom Of Crater
lake may be conceived Of as u nearly
plane surface for the most part, upon
which stand three abruptly rising
prominences, one, Wizard Island, rising
high over the water, the other two
being submerged. The depth of the
floor upon which these pron,inences
stand varies from 800 to 1000 feet,
probably the deepest fresh water in the
United States. The solid contents Of
the area oi the caldera containing this
lake is about ~ cubic miles; the con.
tents of the area oi the mountain top
above the caldcra was probably 8 cubic
cubic miles of material in all.
There is nothing on or around the
present mountain TO account for all
his material.
The evidence does seem to show that
Turing the final activity of Mount
\lazama there must have been within /
I n column Of lava rising to II height Of |
'vcr 5000 feet above the base of the
.ascade range. II is possible tina, this
'rcat pressure. aided, perhaps, by some
'ther forces, made an opening formed /
Nv down upon the mountain slope,
which allowed the lava to escape. The
Of the lava within the noun.
ain left II unsupported and caused It to
ollapsc. Phenomena Of this sort are
veil known In connection with the lila.
'niian volcanoes, The peculiar RI.
ersed How Of lava ut Rugged crest
Gems to point to the collapse and sub.
idencc Of the mountain before the
'ar,iening of this lava. which thcreupon
lowed back and down into the present
aldera, That Mount Mazama disap-
eared and that the caldcra originated
Trough subsistence Seems evident but
he corresponding effusion Of the enor.
nous mass of material upon the lower
urfacc of the mountain, II such effusion
YER occurred, has not yet ieen found.
Crater lake changes level. During
he summer, when there is rapid
Vaporation and little or no prccipita-
on, the surface Of the lake subsidies
ut during the rainy winter it rises
gain. The oscillation il limited To
bout four feet. The lake appears to be
ii chiefly by the vast quantities Of
how which drift across the crest and
dge in great banks ON the inside. The
nnual recipitatlon of the region il
ut between 20 and 80 inches.
rater lake has no visible outlet, nor
~ invisible one reaching the surface
lrectly within u few miles. Hut the
alls of the caldcra enclosing the lake
u made up of alternating sheets Of
va, dipping away from the lake practi-
'lly in all directions, and they are 10