Fig. 16

Images and data of zircons separated from a QB-SZ sample (B20-2801). a–d CL-images, circles show LA-ICP-MS spots and numbers next to it show the corresponding \({}^{206}\hbox {Pb}/{}^{238}\hbox {U}\)-age with one standard error (in brackets). Blue spots indicate LA-ICP-MS measurements of domains with preserved oscillatory zoning (a) or slightly blurred oscillatory zoning (b), and green spots of domains with strongly blurred zoning (c) or almost homogeneous texture (d). e Concordia diagram of all LA-ICP-MS measurements (inner figure) and a close-up view up to 750 Ma (main figure). Data highlighted in green correspond to data shown in subfigure (f) and are potentially respected for the age determination. Outliers referred to as ‘inherited cores’ are marked in yellow. Basis for discarding additional data (non-filled error ellipses) is indicated in Additional file 4. Error ellipses correspond to two standard errors. f Inner figure shows a histogram of all \({}^{206}\hbox {Pb}/{}^{238}\hbox {U}\)-ages shown in the main figure. Main figure shows \({}^{206}\hbox {Pb}/{}^{238}\hbox {U}\)-ages separated into two age ranges based on a depression in the histogram at around 310 Ma. Colors indicate different textures, which correspond to colors in CL-images