What is Geophysics?

Geophysics is an earth science that combines geology and physics. In other words, it is the study of the physics of Earth and other planetary bodies. Planetary science is an example of a field where geophysics is well applied, since the study of planets in space requires the intersection of geology and physics. Geophysics has many branches, including magnetism, seismology and meteorology, so geophysicists work in many areas, from minerals to studying the moon to archeology. Since Earth systems involve rocks, water, air and life, and since the Earth is a part of a system in space, geophysicists can be classified by which of these components they specialize in.

Solid-Earth Geophysics

The branches of geophysics that deal with the solid parts of Earth deal with some of the most mysterious of the planet's processes. Some scientists---solid-earth geophysicists and structural geologists---study the structures and origins of the Earth in fields such as plate tectonics. Seismologists study earthquakes, while volcanologists study volcanoes. Geomagnetists study the Earth's magnetic field. Many solid-earth geophysicists are involved in finding resources like oil, minerals and ore. These scientists might be petrologists or economic geologists. Geodesists can map out the Earth and changes in it so accurately that they can track the movements of tectonic plates.

Geophysics and Water

Some geophysicists work with the processes on Earth that involve water, and with those scientists in other fields who work with water. Those who study the effects of fresh water, including underground water, along with rain and snow are collectively called hydrologists. Those working to understand the oceans and the landscapes beneath them are collectively called oceanographers. Water has an effect on the world on a large scale---for instance, in shaping land, affecting weather and dictating life.

Geophysics and Air

We can view some of the large-scale processes involving air and atmosphere when hurricanes threaten land and thereby garner a lot of news coverage. Understanding and predicting weather, or the sun's effect on the atmosphere, or global warming---these tasks are tackled by atmospheric scientists, meteorologists and atmospheric chemists. An understanding of geophysical processes is necessary to understanding and predicting these phenomena while finding solutions that protect the air against us and us against events originating in the atmosphere.

Space and Geophysics

Just as Earth is subject to the laws of physics and geologic processes, so too are other planets, moons, comets, asteroids and meteoroids. Understanding and exploring other heavenly bodies helps us understand Earth by itself and as as part of a larger system. Planetary scientists are those exploring these other worlds with the help of satellites, probes and telescopes, and also sometimes samples of extraterrestrial matter like meteorites and moon rocks. Those investigating the sun and space---for example, researching solar flares, the interaction of the sun with the Earth's magnetic fields, the causes of magnetic storms and the like---are called solar and space physicists.

Geophysics and Life

Life on Earth and any possible life on other worlds evolved under the influences of physical laws and the geology of the Earth. Studying phenomena at the intersection of life with geology, physics and/or chemistry is the purview of biogeoscientists and biogeochemists. Astrobiologists study forms of life in bizarre places like boiling water or acid, which might lead to finding life in what seems like inhospitable environments on other worlds. Paleobiologists can compare knowledge of climate changes with the fossil record, and apply lessons learned to what is occurring today or what might occur in the future.