The various branches of geology

Geology is a multi-disciplinary subject. Literally Geology means the study of the Earth .
The word GEOLOGY is derived from Ancient Greek word gē, i.e. "earth" and -logia, i.e. "study of".

Geology is a vast science which is devoted to the study of Earth .

It deal with the study to understand the structure of the Earth and its surface features, to study causes of earthquakes and tsunamis and why volcanoes form and erupt.

It is also to learn about minerals, which form the building blocks of rocks, and how rocks are made and destroyed .

It is to learn about Earth’s fascinating history, the variety of life forms which have roamed the surface over the millennia and the dramatic changes that have happened over Earth’s long history etc.

The field of geology is very large and it is divided into several branches:

1.Physical Geology
2.Geo Tectonics
3.Structural geology
4.Geomorphology
5.Crystallography
6.Mineralogy
7.Petrology
8.Stratigraphy
9.Palaentology
10.Economic Geology
11.Engineering Geology
12.Hydro Geology
13.Geophysics
14.Geochemistry
15.Mining Geology

1.Physical Geology:

It is concern with the work of the natural processes which bring about the change upon the Earth's surface.

It deal with the endogenous (Internal)and exogenous (External) agencies and the processes that bring about the changes on the earth surface.

James Hutton is regarded as the father of physical geology.

2.Geo Tectonics :

It concern with the movements of the Earth's crust and the deformation cause by geological processes (mainly endogenous processes).

Geo Tectonics is concerned with the processes which control the structure and properties of the Earth's crust, and its evolution through time. In particular, it describes the processes of mountain building , the growth and behavior of the strong, old cores of continents known as cratons , and the ways in which the relatively rigid plates that constitute the Earth's outer shell interact with each other.

Tectonics also provides a framework to understand the earthquake and volcanic belts .

3.Structural Geology:

It deal with the configuration of the rocks in the Earth's crust produce due to a number of forces generated both exogenously and endogenously.

Structural geology is the study of the three dimensional distribution of large bodies of rock, their surfaces, and the composition of their inside in order to try and learn about their tectonic history, past geological environments and events that could have changed or deformed them.

These can be dated to determine when the structural features formed.

If the nature of these rocks can be determined, petroleum geologists can discover if petroleum, natural gas, or other natural resources are trapped within the rocks.

4. Geomorphology:

It concern with scientific study of the origin and evolution of the relief features (landforms) of the earth.It is the scientific study of the origin and evolution of topographic and bathymetric features created by physical, chemical or biological processes operating at or near the Earth's surface.

Geomorphology concentrate primarily on Quaternary(Pleistocene -Holocene ) features.

5.Crystallography:

It is the study of the external forms and the internal atomic structure of the crystalline materials .

Crystallography is the experimental science of determining the arrangement of atoms in the crystalline solids.

6.Mineralogy :

Mineralogy deal with the study of mineralogy composition ,mode of occurrence and origin, stability,association ,their crystalline and chemical structures, and their properties such as melting points etc .

It also include their utilization for mankind.

7.Petrology :

Petrology is the scientific study of rocks that deals with their composition texture, and structure; their occurrence and distribution; and their origin in relation to physico-chemical conditions and geologic processes.

It is concerned with all three major types of rock : igneous, metamorphic, and sedimentary.

Petrology includes the sub disciplines of Experimental Petrology and Petrography.

Experimental petrology involves the laboratory synthesis of rocks for the purpose of ascertaining the physical and chemical conditions under which rock formation occurs.

Petrography is the study of rocks in thin section by means of a petrographic microscope (i.e., an instrument that employs polarized light that vibrates in a single plane).

Petrography is primarily concerned with the systematic classification and precise description of rocks.

8.Stratigraphy :

It deal with the strata of the sedimentary rocks , their succession ,thickness, age ,variation and correlation etc.

It is a science of description and classification of strata in sedimentary rocks including their interpretation of depositional environments.

It is the study of rock successions and the correlation of geological events and processes in time and space.

9.Paleontology:

It is the study of fossils of plants and animals that are found in the rocks of past geological age.

Paleontology is the science dealing with the fossils of long-deceased animals and plants that lived up to billions of years ago.

It's an interdisciplinary field involving geology, archaeology, chemistry, biology, archaeology and anthropology.

The study of fossil indicate climate,age and environment of deposition of the rock unit in which they are found.

A paleontologist studies the history and process of evolution by examining fossils, the preserved traces of long dead animals and plants.

Using data from fossilized bones, ancient pollen, and other clues, paleontologists dig up the details on past climates and past extinctions.

They tell us about the history of the earth, the evolution of life, and our own place in the world.

10.Economic geology:

Economic geology is concerned with earth materials that can be used for economic and/or industrial purposes.

It deal with their mode of formation ,mode of occurrence and distribution ,the location and exploitation of industrial materials obtained from the earth.

These materials include precious and base metals, nonmetallic minerals, construction-grade stone, petroleum minerals, coal, and water.

11.Engineering geology :

It is the application of geological sciences to engineering study for the purpose of assuring that the geological factors regarding the location, design, construction, operation and maintenance of civil Engineering project such as construction of Dam, Road, Bridges, Tunnels,Buildings etc.

Engineering geologists are concerned with the detailed technical analysis of earth material and the risk assessment of geological hazards.

Their role is to ensure that geological factors affecting engineering works are identified and dealt with.

They assess the integrity of soil, rock, groundwater and other natural conditions prior to major construction projects.

They advise on procedures required for such developments and the suitability of appropriate construction materials.

12.Hydro Geology:

It deal with the Hydrological properties of rocks and the occurrence of ground water,its movements and action.

It deals with the distribution and movement of groundwater in the soil and rocks of the Earth's crust (commonly in aquifers).

Hydrogeology looks at how water interacts with geological systems. But there is more to hydrogeology than wet rocks.

Hydrogeologists are able to give information on groundwater availability and vulnerability.

The best way to conserve the quality of groundwater is to adopt the concept of pollution prevention.

This protects the whole resource and avoids the need for treatment at the point of use.

Expert advice from hydrogeologists helps to develop codes of practice for land-use and planning, and make this concept a reality.

13.Geophysics :

It is concerned with the physical processes and physical properties of the Earth and its surrounding space environment and the use of quantitative methods for their analysis.

The term geophysics refers to the geological applications of physics to study : Earth's Shape; its gravitational and magnetic fields; its internal structure and composition ; its dynamics and their surface expression in plate tectonics etc .

Modern geophysics organizations use a broader definition that includes the water cycle including snow and ice; fluid dynamics of the oceans and the atmosphere ; electricity and magnetism in the ionosphere and magnetosphere and solar-terrestrial relations; and analogous problems associated with the Moon and other planets.

14.Geochemistry:

Geochemistry is the science that uses the tools and principles of chemistry to explain the mechanisms behind major geological systems such as the Earth's crust and its oceans .

The realm of geochemistry extends beyond the Earth , encompassing the entire Solar system and has made important contributions to the understanding of a number of processes includingmantle convection the formation of planets and the origins of rocks.

15.Mining Geology :

Mining geology is an applied science which combines the principles of economic geology and mining engineering to the development of a defined mineral resource.

Mining geologists and engineers work to develop an identified ore deposit to economically extract the ore.

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