Rock formation can be studied using principles of physics.
Because the universe is so complex and interconnected, the various disciplines of science---such as chemistry, geology and physics---often converge together. This creates such hybrid fields as biochemistry and biophysics. Similarly, combining the disciplines of physics and geology creates geophysics, which studies the Earth using the principles of physics.
Definition
Geophysics is the study of the physics of the Earth. It can best be described as a branch of geology, but geophysics is the mediation between the concepts of physics and geology. Fields include geomagnetism, which is the study of Earth's magnetic field, and seismology, which is the study of elastic waves propagating throughout the Earth.
Significance
Similar to the way in which physicists study the universe, geophysicists study the Earth using theories of gravity, magnetism, electricity and seismology. Geophysics involves plenty of field work, but analysis also requires complex computations and calculations. The variety of pragmatic applications of geophysics include the discovery of oil, iron, copper and other resources, the evaluation of environmental hazards and the prediction or study of properties such as plate movement.
Magnetism
The Earth's magnetic field is a product of electrical currents from the convection (or circulation of heat) and rotation of iron and nickel in the liquid metallic outer core. Earth's magnetism resembles a dipolar bar magnet, where the field is strongest at the poles, tilted at approximately an 11-degree angle and projecting far out into space. The study of magnetism is more complex than that, however, because the intensity at different locations on the Earth is not completely uniform.
Plate Movement
Plate tectonics is one field of geology in which geophysicists can apply the properties observed in magnetism. At random intervals usually lasting fewer than a million years, the Earth's poles reverse themselves. When magma cools, new rock formations record the orientation of the magnetic field at the time. Scientists can observe these rocks, which extend away from a ridge as colored stripes, to study the movement of tectonic plates. On each side of the ridge, the rocks appear as mirrored stripes of each other. By studying rocks with similar magnetic characteristics, scientists can analyze homologous, or similarly positioned, formations.
Seismology
As activity occurs within the surface of the Earth, movement produces seismic waves that can be recorded by seismographs. Geophysicists can study high-frequency primary or compressional waves---they arrive first---secondary surface waves of a lower frequency---they do the most damage---and Rayleigh waves, which roll along the ground.
Tags: magnetic field, Definition Geophysics, Earth magnetic, Earth magnetic field, Earth using, physics geology, principles physics
