Mountains

1. Sumayan, Lea Jean S.

2. Most people think of a
mountain as simply a high, or
more or less rugged landform, in
contrast to flat and low land.
Mountains, however, are much
than high country. To a geologist,
the mountain belt means a long,
linear zone in the earth’s crust
where the rocks have been
intensely deformed by horizontal
stresses and generally intruded by

3. Orogenes
is
The process of
mountain building is called
orogenesis. The factors
that appear to be most
important in this process
are:

4.  Rock sequences
Mountain buliding invlolves
the three-phase cycle made up
of:
1. Geosynclinal sedimentation
and contemporaneous
subsidence;
2. Compression and
deformation; and

5.  Structural deformation
This is deformed
structure compression, in
which scale of deformation
ranges from wrinkled grains
or fossils in the rocks to
folds tens of kilometers
wide.

6.  Metamorphism
This refers to
changes in the mineral
composition and texture
of rocks subjected to high
temperatures and
pressure within the earth.

7.  Igneous Activity
This is the concentration
of the earth’s lighter material
in the continental crust
which takes place in two
steps.

8. General
Classification of
Mountains

9. 1. Geographically and
chronologically, according
to their arrangement.
This divides mountains
into cordillera system
ranges, groups, chains,
and singe mountains.

10. This is based upon the
geological processes by which
they have been formed. Volcanoes
are formed where masses of
igneous rocks are built up as a
result of volcanic eruptions
2. Structurally, according to their
geological stratification.

11. Kinds of
Mountains

12. 1. Folded mountains or
complex mountains –
These result fro folding
of sedimentary or lava
beds or may result from
variable resistance to
erosion.

13. 2. Volcanic Mountains
These result from the
accumulation of lava and
pyroclastic of volcanic
events.