1.) Solar Energy (The Sun) → The Earth Is On An Axis - And The Sun Hits The Surface At Varying Angles Causing The Major Climates To Occur On The Planet. The Sun Affects And Influences The Type Of Life That Exists In The Various Regions. It Affects Earth's Weather - Which In Turn Affects Vegetation And Erosion. 2.) Radioactivity (Earth's Core) → Radioactivity Is Responsible For Plate Tectonics - Most Volcanoes - And Earthquakes - Which Are Located Near Plate Boundaries. Radioactivity Makes Mountains - Valleys - Ocean Basins - Lake Beds - Islands - Trenches - And Most Other Landforms.