Geology basically comes from the word “geos” and “logos”. Geos meaning: “everything related to earth” and Logos meaning: “the study of”. It generally involves studying the materials that make up the earth, the features and structures found on Earth as well as the processes that form and act upon them.
Geology also deals with the study of the history of all life that’s ever lived on or is living on the earth now. It entails studying how life and our planet have changed over time. This is a very crucial part of geology.
Definition of Geology
Many geoscientist have come up with their own version of the meaning of geology, though their definitions do not deviate from the original meaning based on the perspective of a modern day Geoscientist.
Here are the various definitions of Geology:
1.) Geology is the study of the Earth, the materials of which it is made, the structure of those materials, and the processes acting upon them.
2.) Geology is the science which treats: (i) The structure and mineral constitution of the globe; structural geology. (ii) The earth’s history as regards rocks, minerals, rivers, valleys, mountains, climates, life, etc.; ie: historical geology. (iii) The causes and methods by which the earth’s structure, features, changes, and conditions have been produced.
3.) Geology is a science that deals with the history of the earth and it’s life especially as recorded in rocks.
4.) Geology is the science of the earth and other celestial bodies and their history as recorded in the rocks. It includes the study of geologic processes of an area such as rock formations, weathering and erosion, and sedimentation.
5.) Geology is a science that studies rocks, layers of soil, etc., in order to learn about the history of the Earth and its life.
6.) Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which they change. It can also refer generally to the study of the solid features of any celestial body.
7.) Geology is the study of the rocks and physical processes of the earth in order to understand its origin and history.
8.) Geology is the science that studies the structure of the earth (or other planets), together with its origin and development, especially by examination of its rocks.
9.) Geology is the science relating to the history and development of the earth’s crust, together with the several floras and faunas which have successively clothed and peopled its surface.
10.) Geology is the scientific study of the earth: its composition, organization, and history. Geologists study everything from how rocks form to how planets begin, and from the movement of sand on beaches or dunes to the forces that drive the movement of the continents.
Read also: The Meaning of Geoscience
Two Main Types of Geology
Geology is a very broad field that can be divided into many more specific branches.
Typically, geology is divided into two categories:
- Physical geology.
- Historical geology.
Physical geology is the study of the solid Earth and the processes that change the physical landscape of the planet. It deals with the study of the physical features of the earth and the processes acting on them which includes features like: Volcanoes, earthquakes, rocks, mountains and the oceans etc.
Historical geology is the study of the history of the earth. Historical geologists focus on what’s happened to Earth since its formation. They also study the changes in life throughout time. In historical geology, you essentially get to travel back in time to the formation of the earth and move forward through time, witnessing the changes in Earth itself and the life on it.
Some Important Branches of Geology
Additional Branches of Geology
- Spectral Geology.
- Benthic Ecology.
- Marine Geophysics.
- Marine Geochemistry.
- Marine Surveying.
History of Geology
Some of the first geological thoughts were about the origin of the Earth. Ancient Greece developed some primary geological concepts concerning the origin of the Earth. Additionally, in the 4th century BC Aristotle made critical observations of the slow rate of geological change. He observed the composition of the land and formulated a theory where the Earth changes at a slow rate and that these changes cannot be observed during one person’s lifetime. Aristotle developed one of the first evidence-based concepts connected to the geological realm regarding the rate at which the Earth physically changes.
However, it was his successor at the Lyceum, the philosopher Theophrastus, who made the greatest progress in antiquity in his work On Stones. He described many minerals and ores both from local mines such as those at Laurium near Athens, and further afield. He also quite naturally discussed types of marble and building materials like limestones, and attempted a primitive classification of the properties of minerals by their properties such as hardness.
Much later in the Roman period, Pliny the Elder produced a very extensive discussion of many more minerals and metals then widely used for practical ends. He was among the first to correctly identify the origin of amber as a fossilized resin from trees by the observation of insects trapped within some pieces. He also laid the basis of crystallography by recognising the octahedral habit of diamond.
In recent years, geology has continued its tradition as the study of the character and origin of the Earth, its surface features and internal structure. What changed in the later 20th century is the perspective of geological study.
Geology was now studied using a more integrative approach, considering the Earth in a broader context encompassing the atmosphere, biosphere and hydrosphere. Satellites located in space that take wide scope photographs of the Earth provide such a perspective.
In 1972, The Landsat Program, a series of satellite missions jointly managed by NASA and the U.S. Geological Survey, began supplying satellite images that can be geologically analyzed. These images can be used to map major geological units, recognize and correlate rock types for vast regions and track the movements of Plate Tectonics.
A few applications of this data include the ability to produce geologically detailed maps, locate sources of natural energy and predict possible natural disasters caused by plate shifts.
Geological studies in the 21st century will become increasingly prominent as humanity confronts daunting challenges in finding natural resources to sustain Earth’s burgeoning population, in mitigating natural hazards that impact huge populations and extensive built infrastructure, and in achieving sustainable environmental stewardship in the context of an evolving Earth habitat.
The world’s population is expected to reach 7 billion by the end of 2011, and about 9.2 billion by 2050, relentlessly increasing the demand for food, fuel, raw materials, and water. Much of this population will continue to be concentrated near dynamic coastal zones, and meeting the requirements of this population and understanding associated impacts on the environment is a key area to which the Earth sciences contribute. The energy demands of this human population are immense and the modern geological approach gears towards solving these potential human need of energy.