Table 2. Comparison of different LA-ICPMS-MDA metrics.
Comparison of five (5) different metrics utilized within this study to interpret the Maximum Depositional Age (MDAs) for each detrital sample (modified from Tucker et al. (2013, 2016), Coutts, Matthews & Hubbard (2019), Herriott et al. (2019), Tucker et al. (2020)). YDZ, Weighted Average and TuffZirc were run via Isoplot 4.15 (Ludwig, 2003), YC2σ via Age Pick Program (2010) G. Gehrels 1 September 2009, Arizona Laserchron Center, and YSP via Herriott et al. (2019).
| Analysis | Dakota Sandstone |
Lower Moreno Hill |
Middle Moreno Hill |
Upper Moreno Hill |
|
|---|---|---|---|---|---|
| YDZ (N = 6) | Final Age | 96.12 | 91.16 | 89.5 | 89.3 |
| Range | +1.6/−2.0 | +2.5/−2.1 | +3.1/−1.8 | +3.4/−2.4 | |
| Confidence | 95% | 95% | 95% | 95% | |
| WEIGHTED AVERAGE (N = 6) | Final Age | 96.5 (±1.6) | 91.4 (±2.9) | 90.2 (±3.7) | 90.5 (±4.9) |
| Confidence | 95.0% | 95.0% | 95.0% | 95.0% | |
| Rejection | 0 | 0 | 0 | 0 | |
| MSWD | 1.2 | 4.2 | 7.9 | 5.1 | |
| Probability | 0.30 | 0.0 | 0.0 | 0.0 | |
| YC2σ (N = 6) |
Final Age | 96.5 ± 2.5 (2.6%) | 90.2 ± 2.3 (2.5%) | 89.1 ± 2.5 (2.8%) | 90.5 ± 3.3 (3.6%) |
| Weighted Mean Age | 96.5 ± 2.3 (2.4%) | 90.2 ± 2.1 (2.3%) | 89.1 ± 2.2 (2.5%) | 90.5 ± 3.1 (3.4%) | |
| Systematic Error | 1.1% | 1.1% | 1.1% | 1.1% | |
| MSWD | 0.3 | 2.0 | 0.0 | 1.3 | |
| TUFF ZIRC (N = 6) | Age | 96.32 | 91.69 | 89.36 | 89.01 |
| +3.19/−1.81 | +3.02/−2.42 | +1.49/−1.79 | +1.69/−1.81 | ||
| Confidence | 96.6% | 93.8 | 87.6% | 87.6% | |
| Group Size | 6 of 6 | 5 of 6 | 4 of 6 | 4 of 6 | |
| YSP | Final Age | 95.19 | 90.21 | 88.67 | 88.82 |
| Error (±2σ) | ±0 (1.26) | ±1.2 (1.65) | ±1.1 (1.52) | ±1.7 (2.1) | |
| MSDW | 0.96 | 1.19 | 1.38 | 0.94 | |
| PoF | 0.46 | 0.312 | 0.247 | 0.418 | |
| Average | 96.1 Ma | 90.9 Ma | 89.3 Ma | 89.6 Ma | |