The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1922-07-06


lphic means change in form and aptlS
describes the source of origin of this
type of rock Igneous and sediment
larry rocks are converted into meta
morphic rocks by various agencies
such as pressure. heat and movement
in such a fashion as to often destroy
any identity of the original rock. A
disqualification occurs that devel-
ops new minerals so that well known
minerals in a common igneOus rock
may be changed to rare ones in q
rather uncommon schist as a meta
morphic result. Gneisses pronounced
"nice'D. marbles. states and quartz
ties are common metamorphic rocks
Earth in the Making.
Having dealt briefly with the ma
terial of the earth's crust. something
must be explained concerning the
processes and agencies that affect this
crustal material.
The three dominant processes are
known as diastrophism. vulcanism
and graduation.
Diastrophism concerns the crustal
movements such as rising and sinking
of coasts flooding of bays and river
valleys folding of mountain ranges
and development of earthquakes.
Vulcanism deals with all move
ments of lava such as form the great
bulk of many mountain ranges. build
ing volcanoes. developing ore bodies
and such processes.
Graduation is by far the most famil-
hands II includes the leveling down
process as well as a building up ac-
tivity.
The deposition of all materials whe-
Their carried by rain, rivers, waves,
wind or glaciers into deltas rivers,
flood plains. alluvial cones and fans.
includes the latter process. Degra-
dation is accomplished by the same
agencies and develops river valleys,
serrated mountains, lake basins
gorges, water falls. caves and count
less familiar photographic features.
The work of the atmosphere in the
form of winds, the land waters as in
streams, underground waters, waves
and currents of the ocean supple
mented by snow ice and glaciers is
sufficient to completely change the
appearance of any land body in
short space of geological time.
1t is in considering the history of
life on this earth that we come into
an awesome realization of geologic
time. The classification of life in the
past and when it lived along with the
events of the period is called histor-
ical geology and a hasty sketch of
previous happenings is desirable to
help the reader understand local geo
logical history.
Beginning of Animal Life.
To properly review a history of life
we must get back to its beginning
We must postulate continents of bar
rem land, at first without soil. An at
mosphere filled with swiftly moving
clouds and a climate of torrential
rains and intense heat. 1t was a per-
iod of volcanic upheavals and great
areas of sediments in deposition to
form land masses of today
The first forms of life were micro
they left no evidence of their exist
ence. Finally as shells were develop
ed a record of their evolution and de-
velopment was provided At first life
was very primitive and simple. AS
age after age passed by different
Of MI oIa
ant diversity of species developed by
natural selection and evolution.
In the earlier ages of life crab-like
animals called trilobites along with
certain shelled animals dominated the
waters of the oceans and seas. AS yet
no life existed on land. Succeeding
them in power came certain coiled
shell animals similar to the Cham
bered Nautilus" of literature. Corals
and sponges gained a place in the
scheme of things.
Progress of the Ages.
About 300 million years Gas estim-
ated by concensus of geologic opinion)
after the beginning of life came the
first FISH and they in turn dominated |
the ocean life of the earth. After |
them came a larger group of animals |
called amphibia giants in size and di-
versified in characteristics able to live |
either in or out of water They were |
the encroachment of animal life on |
The land masses. About this time |
came the growth of vegetation on the I
and, and the development of almost |
imitless swamp forests. Moses, !
ichens and fern-like plants rivalling
modern trees in height and foliage !
made up these ancient forests. AS
myriads of these huge plants reached !
the end of their living cycle they fell
in the swamps to be preserved and !
delivered to us in the form of anthra-
cite and bituminOus coal.
Still another age 400 million years
later than the origin of first cells,
brought with it the dawn of the rep |