K-feldspar single-grain post-IR IRSL dating of modern dune sand in the Salawusu River Valley
Sedimentary records in the deserts are important archives for reconstructing the paleoclimate and pa-leoenvironmental change.In this study,three samples(LJB-MD-01,SCHGCMD-01,and M01)were collected from modem dunes in the Salawusu River Valley in the Mu Us Desert.Quartz single-grain optically stimulated lu-minescence(OSL)dating and K-feldspar single-grain post-infrared infrared stimulated luminescence dating(pIRIR)was used to determine the chronology of the sand dunes.The OSL and IRSL characteristics of the sam-ples and the dose recovery test validate the dating protocols.The results suggest that:(1)the quartz OSL signal is very weak and is not suitable for OSL dating of young samples in the study area.(2)equivalent dose(De)de-termination of K-feldspar using pIRIR170 protocol is reliable,with recycling ratio mostly ranging from 0.9-1.1,and recuperation less than 10％.(3)the anomalous fading rate(g-value)of IRSL50 signals are 1.99±0.20 to 2.72±0.73％per decade and the g-value of pIRIR170 are 0.02±0.03 to 0.69±0.31％per decade,suggesting that the low anomalous fading of pIRIR170 can be neglected.(4)The K-feldspar pIRIR170 ages for the three surface sand dunes,determined using the minimum age model,are 115±15 years,150±20 years,and 25±5 years,respective-ly.These values align closely with the theoretical ages.The central age model estimates for the same dunes are 455±65 years,420±55 years,and 30±25 years,respectively.These estimates are older than the theoretical ages.Thus,the current work suggests that K-feldspar single-grain pIRIR dating is applicable in the study area and pro-vides a new approach for dating sediments,including the Mu Us Desert sediments,where OSL dating technolo-gy is not feasible due to the weak quartz signal.
Mu Us Desertmodern dune sandluminescence datingsingle grainpotassium feldspar
NETL
NSTL
万方数据
