Geological science, a type of Earth science, focuses on the solid and liquid material that makes up our planet. Geologist Greg Hoke studies Earth surface processes, also called geomorphology. He uses radioactive isotopes like beryllium-10 and other tools to explore the rise and erosion of mountains and changes in river beds. Glacial Geologist Lauren Miller Simkins travels to Antarctica to gather sediment. She uses it to study the sea floors of Antarctic ice sheets. Geochemist Ryan Venturelli analyzes the carbon in that sediment to help determine the history of the ice and the lakes and land under it.