Extended Data Table 1 U–Th ages of the crust attached on Xiahe mandible

From: A late Middle Pleistocene Denisovan mandible from the Tibetan Plateau

  1. a[238U] = [235U] × 137.818 (±0.65‰)63; δ234U = ([234U/238U]activity − 1) × 1,000.
  2. bCorrected δ234Uinitial values were calculated based on 230Th age (T), that is, δ234Uinitial = δ234Umeasured × eλ234T, and T is the corrected age.
  3. c[230Th/238U]activity = 1 − e−λ230T + (δ234Umeasured/1,000)[λ230/(λ230 − λ234)](1 − e−(λ230 − λ234)T), in which T is the age. Decay constants (λ) are 9.1705 × 10−6 yr−1 for 230Th, 2.8221 × 10−6 yr−1 for 234U, as calculated in a previous study64 and 1.55125 × 10−10 yr−1 for 238U, as calculated in a previous study65.
  4. dAge corrections, relative to ad 1950, were calculated using an estimated initial atomic 230Th/232Th ratio of 4 (±2) × 10−6.
  5. U–Th isotopic compositions, activity and 230Th age uncertainties are 2σ.
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