To establish the timing of Holocene hydrological environment changes in the front oasis of Shulehe river alluvial fan in Hexi Corridor in Gansu Province

twelve water-laied sediment samples collected from three Holocene strata profiles have been dated by quartz OSL

as well as eight samples of organic silt-mud or silt-peat by

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C.For OSL dating the SAR protocol of coarse quartz was used for ten samples

and the fine grain fraction SAR and MARA protocols for four samples.Comparison of OSL ages obtained from the coarse quartz SAR with those from both the fine grain SAR and the MARA for same samples shows a good agreement within a standard deviation.The cross check between OSL ages and

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C ages for four group samples within same or contiguous layers is accepted in meas- urement error.On the basis of all age estimates obtained from both OSL and

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C

and of analysis of field observa- tion data

an elementary timing of Holocene hydrological environment changes

i.e.shifts of groundwater spilling belt

in the front oasis of Shulebe river alluvial fan is suggested in this paper.