Paleontologists look at fossil records. Petroleum geologists search for and study fossil fuels. Stratigraphers help to find minerals by studying fossil and mineral content of rock layers. Among geophysicists, geodesists study the size and shape of the earth. They also study its gravitational field, tides, polar motion, and rotation.
Physical oceanographers study the physical aspects of oceans.
These include currents and the interaction of the surface of the sea with the atmosphere. Seismologists measure and study earthquakes. Hydrology is an area closely related to geology and geophysics. Hydrologists study the distribution, circulation, and characteristics of underground and surface waters. Their work is important in helping the environment.