Creation [Electronic resources] نسخه متنی

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Creation [Electronic resources] - نسخه متنی

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Creation-Mountain


The surface of the Earth contains many
heights and depressions . Present ridges
are generally seen in the forms of a single
mountain , single mountain ranges and
mountainous landmasses.


There have been many hypotheses concerning
the origin of these ridges and how they have
been created , however , volcanic rocks have
often played a role in their creation . The
common point of all of hypothesis presented
is that these heights have been formed
following some movements which have affected
the structure of the Earth's crust and
created dislocation in its layers . In other
words,the movements caused a dislocation in
the original condition of the layers of the
Earth.Following these movements rocky layers
at the bottom of the seas , lakes and on
the surface of the Earth which are almost
horizontal,lose their original shape,move up
and down,crush and sometime break,and finally
make heights on the surface of the Earth.
Perhops the oldest hypothesis concerning the
appearance of the mountains is that the Earth
gradaally began to cool after its formation;
following the compression resulted from such
a cooling process,some folds were created on
the surface of the Earth. It seems that this
hypothesis is unable to explaine the present
orogeny )the process of mountain formation).
Another hypothesis states that the heat
inside the Earth,which is much more than that
of its surface,causes the Earth to expand and
as a result cracks its surface . The pieces
thus produced give rise to heights and
depressions on the surface of the Earth.
This process occurs on the basis of isostasic
equilibrium ) an equilibrium relationship
among different parts of the Earth ).


Some other hypotheses state that all orgenic
activities must have been and is accompanied
by volcanic activities . These lava create
ridges on the surface of the Earth.


According to Geosynclinal hypothesis most
mountains were created in the margin regions
which used to be the site of condensed and
continous sedimentations . In addition to
the weight of sediments,such phenomenon as
suction in convective movements and lateral
pressures give rise to the depression of
these areas in million of years time.Such
a process repeats many times in the course
of time.According to isostasic equilibrium
a movement in the opposite direction of the
depression is created and gives rise to
heights and mountains.


Studies carried on in recent decades have
considered another theory . Studies and
investigations performed indicate that the
upper layer of the Earth ) Lithosphere ( is
made up of a number of plates which move
slowly on their lower layer )Asthenosphere)
in such a way that the course of their
relative movement is approximately a few
centimeters in a year ) plate techtonic
theory (.On the basis of this theory the
plates which are adjacent to each other
act in the forms of divergence ) Divergent
Boundaries ( , convergence ) Convergent
Boundaries (,or vibration.In the divergent
case lava penetrate to the upper layer and
make it swell.There are two other cases which
generally create lateral pressure,folds,and
heights on the surface of the Earth.


In summary,the factors responsible for the
change in the equilibrium of the Earth's
( solid ( crust such as changes in the
temperature of the Earth , volcanoes,
earthquakes,solar radiations and the change
in the speed of the Earth's rotation,each
have had some suggestions and propositions
as to how mountains were created.It must be
kept in mind that most of the propositions
presented have been founded on the basis of
different processes happening in the depths
of the Earth and most of them are mere
theories.None of these theories have so far
been able to answer all the questions posed
in connection with the formation of mountains

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