A determination from Tegiszhol, in Kazakhstan, records the largest freshwater reservoir offset yet published for the Eurasian steppe: 1071 ± 64 ¹⁴C years, on a human bone sample. A millennium of error in a single date, invisible without the isotopes to catch it.
This project asks a narrow question about the dates underneath steppe Bronze Age chronology: which of them could anyone actually check?
- 1,400
- determinations transcribed from 44 published sources
- 362 (26%)
- on material that can carry a reservoir offset, published with no δ¹³C or δ¹⁵N at all
- 190
- of those on human bone — the highest-risk category
- 76
- sites affected
Why this matters
Two facts sit in the literature without being put together.
The Sintashta → Petrovka → Alakul sequence turns on distinctions of roughly two centuries, and is usually described as beyond what radiocarbon can resolve. Meanwhile, freshwater reservoir offsets on steppe human bone reach over a millennium, vary unpredictably between sites, and are described in the same literature as under-modelled.
Put those together and the sequence problem may be misdiagnosed. “Radiocarbon cannot resolve this” and “an unknown subset of these dates is centuries too old and nobody has worked out which” are different problems with different fixes.
The second one is tractable without excavating anything. It needs the isotopic screening data — and for most of these dates, that data was never printed.
What this is not
This makes no claim that any particular date is wrong. It says only that a large, quantifiable, site-attributed body of determinations carries a documented error mechanism and no published means of testing for it. That distinction is the entire point and it survives into every page here.
Nor is it a criticism of the excavators. Many of these dates were measured decades before reservoir screening was standard practice. The register exists so that new isotopic work can be aimed where it would resolve the most, not to second-guess anyone.
Where new measurement would buy the most
| Site (as printed) | Unscreenable human-bone dates | Age range BP |
|---|---|---|
| Uibat V | 11 | 2740–4016 |
| Saragash Ozero | 9 | 2421–2562 |
| Okunev Ulus | 8 | 2316–3894 |
| Могильник Ушкаттинский I | 7 | 3080–3380 |
| Podgornoye Ozero | 7 | 2166–3011 |
| Verhniy Askiz I | 7 | 2609–3934 |
| 6 | 2890–3730 | |
| Айна-Булак-I | 6 | 2800–3920 |
| ГМ Фирсово-XI | 5 | 6534–9106 |
| Yarki II | 5 | 2511–3348 |
The full register → · How it was built → · What went wrong →