The word Geology is derived from the Greek (geo=earth, logos=study) and deals with the study of the planet Earth, the materials of which it is made, the processes that affect Earth materials, the products formed in the Earth, and the history of the planet and of its inhabitants since its origin. Geologists study the composition of Earth materials and the various geological processes in order to locate and exploit Earth's mineral resources. Geologists also investigate earthquakes, volcanoes and other geological phenomena to predict and minimize the damaging effects from them. They also study geologic history in order to determine former positioning of the continents and oceans, the nature of ancient climates, and the evolution of life as revealed in fossil records.
Earth science and the basic sciences overlap in many areas of investigation. Chemistry is utilized to analyze rocks and minerals of the Earth's crust. Biology is used to aid in understanding the nature of prehistoric organisms. Botany provides information about ancient plants, whereas Zoology is essential in the understanding of prehistoric animals. Physics explains various physical forces affecting the Earth and how it's materials respond to these forces. Astronomy provides answers to where the Earth fits into the universe, and explanations the origin of the Earth. Because of its broad scope, geology has been divided into two major divisions:
- Physical Geology - deals with the composition of the Earth and its structural arrangement, it's movements within on an the Earth's crust
- Mineralogy - the study and classification of minerals
- Petrology - the origin, structure, occurrence and history of rocks
- Structural Geology- the deformations of rocks and their structural attitude of arrangements
- Plate Tectonics- similar to Structural but deals with the Earth's larger structural features
- Geomorphology- the general configuration of the Earth's surface, its origin, development, and classification of landforms
- Economic Geology- how geologic processes and materials can be utilized by man
- Geophysics & Geochemistry - rely on data derived from the study of the physics and chemistry of the Earth
- Seismology - study of earthquakes and Earth's interior
- Volcanology - study of volcanoes, their activity
- Glaciology - study of glaciers and their phenomena
- Environmental Geology- relating to human environmental concerns
- Engineering Geology - application of geological sciences to engineering practices
- Marine Geology- deals with the ocean floor and the ocean-continent margins
- Historical Geology- concerned with the evolution of the earth and its inhabitants from their origin to the present day
- Stratigraphy- the study, interpretation, and correlation of rock strata
- Paleontology - the study of prehistoric plants and animals as revealed by their fossils and relation to the chronology of the Earth's history
- Geochronology - the study of time in relationship to the history of the Earth
- Paleogeography - deals with the physical geography of all or part of the Earth's surface at some time in the geologic past
- Paleoclimatology- study of climates of the geologic past
- Paleoecology- study of the relationship between ancient organisms and their environment
- Paleomagnetism - the study of the nature of the earth's magnetic field over geologic time
- Mircopaleontology - the study of fossils too small to be studied without a microscope
The major branches of historical geology, like those of physical geology, overlap in a number of areas and are interdependent. The unification of physical and historical geology leads ultimately to a better understanding of the Earth.
Although geology is a relatively young science, humans have long been interested in the Earth. Prehistoric people utilized stones as tools and weapons, formed clay into pottery, and sought shelter in rocky caves. But their knowledge of the earth was restricted to the ground beneath their feet or the limited areas that they could explore on foot.
Now, with the use of technology, humans are delving further into the Earth's structure. With this advancement also comes the opportunity to be able to find and exploit more of the Earth's resources.
