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U-series dating of pedogenic carbonateclast coatings provides a reliable, precise minimum age of 45.1 +/- 0.6 ka (2 sigma) for the T2 geomorphic surface of the Biskra Palms alluvial fan, Coachella Valley, California. Concordant ages for multiple subsamples from individual carbonate coatings provide evidence that the U-238-U-234-Th-230 system has remained closed since carbonate formation. The U-series minimum age is used to assess previously published Be-10 exposure ages of cobbles and boulders. All but one cobble age and some boulder Be-10 ages are younger than the U-series minimum age, indicating that surface cobbles and some boulders were partially shielded after deposition of the fan and have been subsequently exhumed by erosion of fine-grained matrix to expose them on the present fan surface. A comparison of U-series and Be-10 ages indicates that the interval between final alluvial deposition on the T2 fan surface and accumulation of dateable carbonate is not well resolved at Biskra Palms; however, the "time lag" inherent to dating via U-series on pedogenic carbonate can be no larger than similar to 10 k.y., the uncertainty of the Be-10-derived age of the T2 fan surface. Dating of the T2 fan surface via U-series on pedogenic carbonate (minimum age, 45.1 +/- 0.6 ka) and Be-10 on boulder-top samples using forward modeling (preferred age, 50 +/- 5 ka) provides broadly consistent constraints on the age of the fan surface and helps to elucidate its postdepositional development.