A geologist is a scientist who studies the solid and liquid matter that constitutes the Earth and terrestrial planets. Geologists usually engage in studying geology and approach this using mathematics, physics, chemistry, and biology as well as other sciences.
The mathematics required for a geologist includes but is not limited to College Algebra, Geometry, Trigonometry, Calculus I and II, Linear Algebra, Differential Equations, and Statistics.
In order to find the average income of a geologist, please use this link.
For more information about geology, the US Bureau of Labor Statistics breaks down the job of a geologist into multiple sections to help better understand the requirements of being a geologist.