Geology is the scientific study of the earth. It is concerned with the structure and composition of the earth, the physical processes at work on and within the earth, and with earth history, including its formation and subsequent evolution.
As such, geology involves a wide field of study and a variety of techniques drawn from other scientific disciplines. In recent times, it has even been extended to include the other planets of the Solar System.
Among the more important fields of study of geology are the study of rocks and minerals (Petrology and Mineralogy), volcanoes (Volcanology), fossil remains (Paleontology), and landforms (Geomorphology).