Ключевые слова: boulder, cartoon, clay, core, crust, cut, earth, ecology, environment, exploration, formation, foundation, geologic, geological, geologist, geology, globe, grass, ground, heat, heavy, illustration, inside, lava, layer, layered, level, lithosphere, mantle, marble, natural, nature, planet, research, rock, root, rough, sand, sandstone, science, section, sedimentary, soil, solid, sphere, stone, structure, temperature, world,