There has been a recent small flurry of re-interest into the application of OSL dating to sediment trapped in freshwater carbonates, such as:
1) Ribeiro et al. (2014) OSL dating of Brazilian fluvial carbonates (tufas) using detrital quartz grains. QI (online view)
2) Ibarra et al. (2015 in press) Fluvial tufa evidence of Late Pleistocene wet intervals from Santa Barbara, California, U.S.A. PPP (in press)
Which build on the early work of Rich et al. (2003) Optical dating of tufa via in-situ aeolian sand grains: a case example from the Southern High Plains. QSR 22, 1145-1152.
This has got me thinking. It would be a good time to revisit the Naukluft Mountains of Namibia and see if there is any role for luminescence dating to complement the younger-end of the wonderful deposits in the Naukluft Mountains, which I worked on with Peter VanCalsteren, Louise Thomas and Heather Viles back in 2006-2010.