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8 good questions and answers: "Dating - Dating methods chart - How it works"

Annual cycles (how it works)

Variation on basis of yearly seasonal processes

Varve chronology (how it works)

Yearly erosion and sedimentation depending on yearly conditions

Ice layer counting (how it works)

Milankovitch cycles (how it works)

Cosmogenic nuclides (how it works)

Nuclides formed by cosmic radiation in the atmosphere or on the surface of the planet
Unstable
Decay fast to a more stable daughter

U-Th / U-series (how it works)

Radioactive uranium-234 is water-soluble and can be deposited in any mineral formed from any form of water
Decays overtime to various daughter isotopes, which are not water-soluble and therefore stay in the mineral
The uranium/daughter product ratio is then used to measure the time since the uranium was first deposited

K-Ar and Argon-Argon (how it works)

Time is estamated through measuring the parent/daughter ratio within the minerals studied

Optically Stimulated Luminescence (how it works)

Decay of unstable elements causes a shift in electron position within a sample, resulting in a build-up energy that can be released by optical stimulation
The light irradiated by the sample upon this release (called relexation) is proportional to the build-up energy caused by the decay process, which is time dependant