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For example, the principle of superposition is based, fundamentally, on gravity.
In order for a layer of material to be deposited, something has to be beneath it to support it.
The layers of rock are known as "strata", and the study of their succession is known as "stratigraphy".
Fundamental to stratigraphy are a set of simple principles, based on elementary geometry, empirical observation of the way these rocks are deposited today, and gravity.
Geochronologists do not claim that radiometric dating is foolproof (no scientific method is), but it does work reliably for most samples.
In such a situation, the "principle of superposition" is easily applied, and the strata towards the bottom are older, those towards the top are younger.
They are applied by geologists in the same sense that a "null hypothesis" is in statistics -- not necessarily correct, just testable.
In the last 200 or more years of their application, they are valid, but geologists do not assume they are.
It can't float in mid-air, particularly if the material involved is sand, mud, or molten rock.
The principle of superposition therefore has a clear implication for the age of a vertical succession of strata.
However, note that because of the "principle of cross-cutting relationships", careful examination of the contact between the cave infill and the surrounding rock will reveal the true relative age relationships, as will the "principle of inclusion" if fragments of the surrounding rock are found within the infill.