Table 1.

U–Th activity ratios for Law Dome subglacial carbonates

Sample No.Laboratory number and dateU (μg g−1)[230Th/238U]*[234U/238U]*[232Th/238U][230Th/232Th]Age (ka)[234U/238U]i
Løken-DD1UMA01525, January 20071462.325 (11)4.4301 (94)0.02635 (82)8872.4 (0.6)5.208 (11)
Løken-DD2UMA01526, January 20071502.2987 (79)4.3750 (99)0.0409 (14)5672.2 (0.6)5.138 (12)
  • *Activity ratios determined after Hellstrom (2003).

  • Age in kyr BP corrected for initial 230Th using equation (1) of Hellstrom (2006), the decay constants of Cheng et al. (2013) and a [230Th/232Th]i value of 1.5 ± 1.5.

  • Initial [234U/238U] ratios calculated using corrected-age 2 sigma uncertainties in brackets are of the last two significant figures presented.