Neither figure is wrong in the sense of being fabricated — both are legitimate translations of the laboratory measurement, using different conventions and different calibration states.

But the spread between them illustrates why the single date cannot support the weight of precise chronological argument that it was sometimes asked to bear.

The freshwater reservoir effect adds an additional layer of potential shift on top of this already substantial uncertainty.

If the reservoir effect in the Snake River system at the relevant period was, say, 500 radiocarbon years — a plausible if moderate estimate — the true radiocarbon age of the woman would be approximately 10,175 BP rather than 10,675 BP, which would calibrate to a calendar age several centuries younger.

If the reservoir effect was 1,000 radiocarbon years — a large but not extreme value for carbonate-rich river systems — the true age would be substantially younger still.