Rocks found on the Moon are between \(3.1\) and \(4.47\) billion years old. By contrast, the majority of the Earth's surface is made of oceanic crust that is less than 200 million years old, and the very oldest Earth rocks are about 4 billion years old. If the Earth and Moon are essentially the same age, why is there such a disparity in the ages of rocks on the two worlds?

A fascinating aspect of lunar geology is how well it preserves the Moon's history. Unlike Earth, the Moon lacks an atmosphere and the geological activity that reshapes our planet's surface. Lunar rocks, aging between 3.1 and 4.47 billion years old, act as time capsules, enabling scientists to glimpse the solar system's early history.

Due to the absence of plate tectonics and weathering processes on the Moon, the impact craters and mare basalts formed billions of years ago remain relatively unchanged. This static preservation is starkly different from Earth, where geological activities such as earthquakes and volcanoes constantly create, alter, and recycle rock material. The older surfaces on the Moon, therefore, offer us a window into the past, untouched by the processes that tend to erase or bury evidence on Earth.

Plate tectonics is the driver behind Earth's dynamic surface. It describes the continuous movement of Earth's lithospheric plates over the malleable asthenosphere. This theory explains the creation of new crust at divergent boundaries where plates pull apart, like the mid-ocean ridges, and the destruction of older crust at convergent boundaries where one plate subducts beneath another.

These plate movements are responsible for the dramatic reshaping of our planet's surface over millions of years, leading to the formation of mountain ranges, deep-sea trenches, and frequent volcanic and seismic activities. The constant recycling of Earth's surface due to plate tectonics results in a much younger geological profile when compared to the Moon.

Earth's geological processes are numerous and can be extremely powerful. Erosion, caused by water, wind, and ice, wears away rocks and soil, continually reshaping the landscape. Weathering breaks down rocks both chemically and physically. Furthermore, volcanic activity adds new rock to the surface, both on land and under the oceans, contributing to the creation of new crust.

These processes, together with plate tectonics, mean that Earth's surface is constantly being recycled. As new rock forms, old rock is pushed beneath the plates and re-melted into the mantle. This cycle explains why Earth, despite being nearly as old as the Moon, has much younger surface rocks. The oldest rocks on Earth, at about 4 billion years old, are vastly outnumbered by those formed more recently due to the planet's vigorous geological activity.