That's a bit of a mix-up! While fossils are incredibly important for understanding Earth's history, they are primarily used by paleontologists, who study ancient life.

Interior geologists focus on the Earth's inner workings, like the mantle and core. They use indirect methods like:

* Seismic waves: By studying how seismic waves from earthquakes travel through the Earth, we can infer the composition and structure of the Earth's interior.

* Magnetic field: The Earth's magnetic field provides clues about the molten iron core.

* Heat flow: Measuring heat flowing from the Earth's interior helps us understand processes like mantle convection.

* Volcanic eruptions: The composition of volcanic rocks provides insights into the composition of the mantle.

* Meteorites: Some meteorites provide a glimpse into the composition of the early Earth.

So, while fossils are incredibly important, they're not the tools used by interior geologists.