Figure 9. Tera-Wasserburg disagrams showing U-Pb age data (error ellipse=2 SE) for sample Baz 2 and HAB1 (A and B). Gray areas around discordia represent 2 SE uncertainty of linear regression. Analytical precision (age, initial 207Pb/206Pb) is indicated as analytical uncertainty (first value, 1 sigma), “studentized 100(1-α)% confidence interval for t using the appropriate number of degrees of freedom” (second value) and “approximate 100(1-α)% confidence interval for t with over-dispersion, calculated as z=y√MSWD” (value 3). MSDW=mean squared weighted deviations, n=numbers of spot analyses. The U-Pb data ellipses are color-coded according to their 238U/206Pb value, displayed in the individual color scales at the right margin of the diagrams. Data points plotting to the left of the concordia were excluded from age regression; some outliers were also excluded, which plotted off the main regression line, without altering the original age estimate, but improving precision and MSWD values. Graphic presentation and age calculation utilized IsolpotR (Vermeesch, 2018).
Table 3. Sample details with U-Pb age results