The total measurement uncertainty on matrix corrected ages obtained during line scan analyses is slightly worse compared to spot mode (1.7-1.9 % vs. 2.3-2.8 %, Table ). This is mainly owed to the higher 87 Sr/ 87 Rb ratio uncertainty in line compared to spot mode (2sx = 0.5 -1.7 % vs. 0.3 -0.7 %, Table ) and the higher long-term excess variance on 87 Sr/ 87 Rb ratios (1.4 mapping session consists of 5900 shots with a 3 µm beam, while a single spot analysis during session "GER2B/WilA" consists of 400 shots with a 65 µm beam. Assuming a constant ablation depth per shot, this results in a ~31.8 times more sample volume during a single spot analysis as opposed to line scan analyses.