how might a geologist study the history of earth?

Geology is the study of the Earth - how it works and especially its 4.5 billion-year history. Geologists study some of society's most important problems, such as energy, water, and mineral resources; the environment; climate change; and natural hazards like landslides, volcanoes, earthquakes, and floods.

C14 dating since carbon is present in both living and no living objects .

Hmmm i'm not sure about this one