Many geoscientists specialize in one area of study. Among geologists, marine geologists or oceanographers study marine geology. They study the relationship between the coast and the sea. Mineralogists study minerals and precious stones. 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.