introductory chapter portrays basics of coal, its formation and deposits. Also
it deals with the application of remote sensing and GIS in mapping and
monitoring of mining hazards as well as literature review related to the
objectives of Land Use/Land Cover classification, Digital Elevation Model
generation, mapping and monitoring of land subsidence as well as land
degradation and finally the vulnerability assessment of those hazards.
The word coal is a modified form of an old English
word col of Germanic origin. It is
related to the Dutch word kool and
German word kohle. All these three
words resemble to a piece of glowing carbon or charred remnant used as fuel.
Coal is basically considered to be a fossil fuel and is found in abundance in
the earth. There are three types of rocks present on the surface of the earth
-igneous, sedimentary and metamorphic. The coal is also considered as rock of
sedimentary origin. It is a readily combustible black or brownish-black
sedimentary rock. However, few varieties of coal can be regarded
as metamorphic rock because of later exposure to elevated temperature and
pressure. It is primarily composed of carbon along with variable quantities of
other elements, chiefly sulfur, hydrogen, oxygen and nitrogen.
its introduction to human being, coal is used as an energy source basically for
production of electricity, household uses and in steam engines. It is also used
for industrial purposes such as in heat chambers for refining of metals and
various other rationales.
Formation of coal
Coal is nothing but a decayed product of plants,
mainly big trees, which have died and buried under soil, hundreds and millions
of years ago. Most of the coals that we use today are considered to be formed
about 300 million years ago, when maximum part of the earth was covered with
steamy swamps. Various earth processes like flooding, earthquakes and
landslides have helped in burying down of large forest covers underneath soil.
As the time progresses the thickness of soil cover lying over the trees
remnants have increased which compressed the tree remnants leading to fast
decaying of these trees as the temperature also rose due to these overlying
soil. Due to the continuation of this process, the forest matter was protected