Theory 28/Geomorphic events/Cosmogenic dating
Events Are Dated, Not Inferred
The claim
The timing of a surface event is set directly by the ratio of accumulated cosmogenic nuclide to production rate, so a date comes from the surface rather than from a stratigraphic correlation.
01Mechanism
Cosmic rays produce nuclides in exposed rock at a known rate; exposure time follows from the accumulated concentration.
02Prediction
Dates should agree across independent nuclides.
03Refutation
Systematic disagreement between nuclides would undermine the chronology.
04What makes it checkable
Improved production-rate calibrations and measurement precision now allow single-event dating at the resolution of individual landslides and earthquakes.
05Why it was not testable before
Earlier production rates were uncertain enough that dates spanned millennia.