| Summary: | <p>We introduce a set of methods for analyzing
cosmogenic-nuclide depth profiles that formally integrates denudation and
muogenic production, while retaining the advantages of linear inversion for
surfaces with inheritance and age much greater than zero. For surfaces with
denudation, we present solutions for both denudation rate and total
denudation depth, each with their own advantages. By combining linear
inversion with Monte Carlo simulation of error propagation, our method
jointly assesses uncertainty arising from measurement error and denudation
constraints. Using simulated depth profiles and natural-example depth
profile data sets from the Beida River, northwest China, and Lees Ferry,
Arizona, we show that our methods robustly produce accurate age and
inheritance estimations for surfaces under varying circumstances. For
surfaces with very low inheritance or age, it is important to apply a
constrained inversion to obtain the correct result distributions. The
denudation-depth approach can theoretically produce reasonably accurate age
estimates even when total denudation reaches 5 times the nucleon
attenuation length. The denudation-rate approach, on the other hand, has the advantage of allowing direct exploration of trade-offs between exposure age and denudation rate. Out of all the factors, lack of precise constraints for
denudation rate or depth tends to be the largest contributor of age
uncertainty, while negligible error results from our approximation of
muogenic production using the denudation-depth approach.</p>
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