The migration speed of a typical barchan on the border of Minqin oasis, Gansu Province, northwestern China, was estimated by means of two methods. One is on the basis of a simple physical model and short-term field measurements. The other comes from the combination of the barchan internal structure detected by ground-penetrating radar and optical/radiocarbon dating techniques. The upper limit of migration speed given by conventional C-14 dating is 3.42 m/yr. The optically stimulated luminescence dating indicates that the time-average migration speed of the studied barchan was 1.78 m/yr in 28 years prior to 2007. The physical estimation further suggests that the annual migration speed has increased in recent years.

The work presented here suggests the following:
(1) Both methods, i.e., dating and physical models, are valid for estimating barchan migration in this study, al-though dating techniques need to be improved.
(2) The upper limit of the time-average migration speed of the barchan, given by the conventional C-14 dating, is 3.42 m/yr.
(3) The time-average migration speed of the barchan, based on OSL dating, is 1.78 m/yr in the 28 years prior to 2007.
(4) The annual migration speeds of mobile dunes in the Minqin region have increased in recent years.