Density distribution and Wetherill Concordia diagrams for U-Th-Pb dated zircons from samples MTS5, MTS6 and MTS18. A1, B1 and C1 are kernel density plots. A2 shows the Concordia of the whole dataset for sample MTS5 and A3 shows only the younger population with the weighted mean ²⁰⁶Pb/²³⁸U age calculation. B2 contains a Concordia between 150 and 500 Ma to show only the main age groups in sample MTS6. B3 shows the Permian-Triassic population and the age calculation in the same sample. C2 contains a Concordia up to 1000 Ma to show the main age groups in sample MTS18, and C3 shows the Permo-Triassic population with age calculation.