In conjunction with other types of measurements, such information can be used to draw cross sections of the upper crust. On a smaller scale, the electrical properties of the rock surrounding a wellbore are measured to enable a petrophysicist to calculate the amount of pore space and the type of fluids in the pores of the rock. Such tests are now routinely run in the wells drilled in the oil and gas industry. Geophysicists must be familiar with structural geology and stratigraphy, key related areas. In Canada, most students take a geophysics degree in an earth sciences department through a four-year physics programme with a geology minor.
Geophysicists also come from pure physics, pure mathematics or engineering programmes.
A four-year B.Sc. degree is a basic requirement, and a M.Sc. is commonly preferred. Most graduates are employed by companies and consultants within the petroleum industry. Environmental hazard assessment, geothermal energy evaluation and earthquake detection are fields of expanding importance requiring a geophysics background.