Our home planet “The Earth” is a member of the great Sun’s family termed as the solar system. Also known as the ‘Blue Planet’, it is the only heavenly body of revolution that has a delicate balance of physic-chemical conditions which support sustenance of life that is unique and special to our beloved mother earth.
Geology is a natural scientific discipline and is a term derived from the summation of two ‘Greek’ words such as ‘Ge or Geo’ meaning the earth and ‘Logos’ meaning science or discourse. In one telling sentence, it pertains to the study of the earth as a whole or part thereof.
In a broader sense, geology could be reframed as ‘Earth Science’ which considers the whole earth as a giantly closed system which is ever dynamic and a mosaic of four interactive parts that is ever changeable both among and within them.
These four parts are called four reservoirs of materials of the earth which also represent the four open systems such as (i) THE ATMOSPHERE which surrounds the earth’s surfacs as a continuous canopy (layer) composed of a gaseous mixture of nitrogen (N), oxygen (O), hydrogen (H), carbon dioxide (COJ and water vapour (H,01). (ii) THE HYDROSPHERE which forms the storehouse of earth’s total water regime comprising the oceanic and sea water, stream (river) water, lake water, surface run-offs, frozen water in form of snow and ice, and underground water (iii) THE GEOSPHERE which is the solid earth composed of soils, regolith (loosely cemented rock particles), solid rocks, layers of rock-metal association and metallic alloys (Fe-Ni), as is observed and interpreted from the top towards the centre of the earth, (iv) THE BIOSPHERE which forms the earth’s organic world comprises of the living beings and the undecomposed organic matters.
This sphere persists through all the aforesaid spheres. Biosphere is considered as an informal sphere as against the former three which are the formal ones.
Geology, as a word was first used by the Swiss natural scientist named Jean – Andre Deluc in 1778 and was later introduced as a formal and fixed scientific term by Horace – Benedict de Saussure.
The term ‘Geology’ or the ‘Earth Science’ in a nutshell pertains to the scientific study of the earth, its composition, structure, physico-chemical attributes, developmental history and above all the natural processes which shape it. The earth is essentially a closed system or very close to it in which the energy reaches the earth from the sun and eventually returns to the space as long wave radiations.