Nine calcareous nodule samples obtained from a loess profile in Luochuan of China were dated with ESR using "BL" signal at g = 2.0038. Agreement between ESR ages and stratigraphic ages was observed for four samples from Q 2 and Q 3 strata
but ESR ages of the samples from Q1 stratum were far too small due to the redeposit of carbonate originated from groundwater. Futhermore
results showing the properties of "BL" signal were also reported.