As the Earth took shape—a process of accumulating space debris after the Big Bang—it formed a core, following physics rules of gravity, etc.  The central core was eventually composed of iron, but the outer crust, acted upon by various forces such as eruptions, tectonic plate movements, formation of oceans, etc., became an admixture of all sorts of elements and compounds and mixtures—silicon-based mountains and deserts, carbon-based vegetation pockets (oil and gas), and many other forms—and is still forming, changing, nonconsolidated. The various geological transformations taking place today, erosion, eruptions, etc., are part on an ongoing process eventually leading either to consolidation or disbursement, depending on other nonEarthly forces—the Sun, meteors, asteroids, etc.—and to a lesser degree, the actions of Man on the planet.