geology
The scientific study of the Earth's physical structure, history, and processes.
He is majoring in geology at university.
Knowledge of geology is useful for resource exploration.
地球科学 (earth science) is a broader term encompassing geology, oceanography, meteorology, etc. 地質学 is a core subfield.
Compound of 地質 (chishitsu, 'geological features') + 学 (gaku, 'study'). The term is a direct translation of the Western concept of geology.