冰川沉积释光测年： 采样策略与测试选择

欧先交,曾兰华,陈仁容,姚盼

Luminescence dating of glacial sediments： sampling strategies and measuring choices

Xianjiao OU,Lanhua ZENG,Renrong CHEN,Pan YAO

图5 英国爱尔兰海东支古冰川沉积3个冰水砾石的释光年代-深度曲线［44］；每一个数据点代表不同深度岩石切片的年代，蓝色和红色分别为IRSL50和post-IR IRSL225年代；同一个砾石在表层2~7 mm深度范围内（2~7个岩片）IRSL50年代非常接近，形成所谓的“年代坪区”；反映砾石在埋藏前曝光充分，上部2~7 mm内IRSL50释光信号完全晒退；图中的实线指示这部分岩片的平均年龄

Fig.5 Luminescence age-depth profiles for three glaciofluvial cobbles from eastern sector of Irish Sea Ice Stream sediment［44］； Data points indicate luminescence ages of rock slices at different depth； Blue and red dots are IRSL50 and post-IR IRSL225 ages respectively； IRSL50 ages are consistent within the surface 2~7 mm （2~7 rock slices）， which form age plateaus； This indicates that these cobbles had been exposed sufficiently and IRSL50 signal of the surface 2~7 mm had been completely bleached prior to burial； The solid lines show the average ages of rock slices at the plateau part