Eli5 archaeological ground cover question


Eli5: They recently uncovered an ancient city wall near to where I live. How does an ancient structure like a wall get covered by layers of ground?

In: 2

Earthquakes, Landslides, Rivers changing course over time and then shaping the landscape. Also just the ambient accumulation of topsoil from continual cycles of growth, death, and decomposition on the ruins (plant grow, plant die, plant dead matter eventually broken down by decomposers into basically just more dirt), winds bring in dust which while subtle and small can accumulate over time, especially when manmade structures provide areas for said dust to get stuck and out of the wind once brought in.

1. The weight of the wall might make it sink over hundreds of years

2. Earth moves and might pile up around a wall

3. The wall can get knocked down (either by people or nature), which makes the other stuff a lot easier

4. Someone might build something on top of the wall, piling up a foundation around it.

4. Probably other factors as well