| Abstract: | 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. |
