What are the key features of the Earth's geographical layers?.

The Earth is composed of three main geographical layers: the core, mantle, and crust. The core consists of a solid inner core and a liquid outer core, primarily made of iron and nickel. The mantle, located above the core, is semi-solid and drives plate tectonics. The crust is the outermost layer, varying in thickness and containing landforms and ocean basins. Each layer has distinct properties crucial for understanding Earth's geology and processes.