How fast can dungeons be covered and how low can they sink?

My plot is to have temples,castles and cities built on top of the remains of previous structures repeatedly to create a multi-level underground dungeon. My goal is to figure out how many levels this dungeon can have as it ages, and what its height relative to the land around it will be.

https://en.wikipedia.org/wiki/Subsidence of buildings seems to be a common enough thing. In addition, it seems like the ground underneath structures is depressed in comparison to the level of the surrounding land. At the same time, layers of dust and dirt are continually laid down, and life builds on top of it all. This seems to be called Silting, and it is the process that lays down strata.

How would one calculate the rate of silting of large stone structures,ie how long does it take for a structure to be covered in layers of earth, and what calculations are there for the isostatic subsidence of land with large stone structures on them.

For example, how long would it take before a city with a 25 square km area, a max height of 65m, and an overall weight of 2 million tonnes, located in a subtropical dry forest, was covered in 1 m of earth

posted about 7 years ago

Eloc‭

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