About Geology and Geologists
What is Geology?
Geology is the scientific study of Earth, a complex, dynamic planet whose interior and surface are subject to continuous modification by a variety of processes. Geology aims at documenting and understanding these processes and how they have changed through time. This is achieved through studying rocks - their composition and properties, the sequence in which they occur, the minerals and fossils they might contain, their age and relationships to one another. Every rock contains a record of its history and the process by which it formed. Geology aims to read that record through scientific investigation, and using the information to reconstruct Earth history and processes, and to locate mineral deposits for use in developing and developed countries.
Recumbent fold, Cape Supergroup; Cape Fold Belt
Our planet is dynamic. Earth has a molten nickel-iron core that is responsible for the Earth’s magnetic field. Energy escaping from the core is expended at the surface of the Earth by the moving of the large lithospheric plates and by volcanism. Plate movements are responsible for creating many of the surface features of the planet including large fold mountain belts such as the Andes and Himalayas, and are also responsible for the formation of basins in which sediment eroded from these mountains is finally deposited. Earth has, with time, evolved into a chemically differentiated planet, as geological processes have resulted in the formation of the iron core, silicate outer solid Earth, the oceans and atmosphere. The origin and evolution of life on Earth is intimately related to the geological evolution of the planet.
The evidence for the complex evolution of Earth and the interaction of its different parts lies in rocks formed throughout Earth history. In Geology one learns to search for this evidence and to decipher the message in the rocks. In this regard Geology is largely a descriptive, interpretive and historical science. This is not to say that Geology is not a true science or is non-quantitative. Much of the “description” in modern geological studies involves obtaining a wealth of quantitative data and the “interpretation” requires rigorous analysis of such data. It is well to remember that the Earth is a complex chemical system subject to a variety of physical forces. Sound knowledge of the laws of chemistry and physics is a powerful tool for a geologist. Another important factor in geology is time. The Earth is 4600 million years old, an intangible quantity in human experience. The magnitude of the time periods within which geological evolution operates sets Geology apart from other sciences (except Astronomy).
What is a Geologist?
Folded Nama Group sedimentary rocks
Geology graduates worldwide are trained in a fundamentally similar range of subjects, which encompass the breadth of geological subdisciplines. These include mineralogy, igneous, metamorphic and sedimentary petrology and petrography, structural geology, geochemistry, palaeontology, ore deposit geology and petrography, hydrogeology and geophysics. More specialised subjects may also be offered at introductory levels. Geologists may specialise in specific subdisciplines at post-graduate level, especially through advanced research during M.Sc. and Ph.D. degrees.
Geologists with this broad training are then employed directly in a variety of fields, including the following professions (among others):
• researcher / lecturer (at universities)
• mine geologist (guiding mineral extraction)
• exploration geologist (finding new ore deposits)
• mapping geologist (for geological surveys)
• petroleum geologist (oil and gas exploration and development)
• groundwater geologist
• museum curator / researcher
• national park conservator
Geophysicists and mining engineers are typically physicists or civil engineers with some geological training, rather than the other way around. Geologists are fundamentally "applied natural scientists", who take aspects of chemistry and physics and apply them to problems in Earth Science.
