1 2Obtaining quantitative information about the timescales associated with sediment transport, 3 storage, and deposition in continental settings is important but challenging. The uranium-series 4 comminution age method potentially provides a universal approach for direct dating of 5 Quaternary detrital sediments, and can also provide estimates of the sediment transport and 6 storage timescales. (The word "comminution" means "to reduce to powder," reflecting the start 7 of the comminution age clock as reduction of lithic parent material below a critical grain size 8 threshold of ~50 m.) To test the comminution age method as a means to date continental 9 sediments, we applied the method to drill-core samples of the glacially-derived Kings River Fan 10 alluvial deposits in central California. Sediments from the 45 m core have independently-11 estimated depositional ages of up to ~800 ka, based on paleomagnetism and correlations to 12 nearby dated sediments. We characterized sequentially-leached core samples (both bulk 13 sediment and grain size separates) for U, Nd, and Sr isotopes, grain size, surface texture, and 14 mineralogy. In accordance with the comminution age model, where 234 U is partially lost from 15 small (<50 µm) sediment grains due to alpha recoil, we found that ( 234 U/ 238 U) activity ratios 16 *Manuscript Click here to view linked References 2 generally decrease with age, depth, and specific surface area, with depletions of up to 9% relative 17 to radioactive equilibrium. The resulting calculated comminution ages are reasonable, although 18 they do not exactly match age estimates from previous studies and also depend on assumptions 19 about 234 U loss rates. The results indicate that the method may be a significant addition to the 20 sparse set of available tools for dating detrital continental sediments, following further 21 refinement. Improving the accuracy of the method requires more advanced models or 22 measurements for both the recoil loss factor f and weathering effects. We discuss several 23 independent methods for obtaining f on individual samples that may be useful for future studies. 24