what does a geologist study
A geologist is someone who is involved in the study of the outer layer of the earth's crust, and who works to understand the history of the planet we live on, to better predict the future, and to explain current occurrences.
Colors indicate the distribution of different rock types across the continent. Geology (from the Ancient Greek γῆ, gē, i.e. earth and -λoγία, -logia, i.e. study of, discourse) is an earth science concerned with the solid Earth, the rocks of which it is composed, and the processes by which they change over time. Geology can also refer to the study of the solid features of any terrestrial planet or natural satellite, (such as Mars or the Moon).