Table 3. Barranc de la Boella radiometric dates obtained from sedimentary samples from stratigraphic units I and II at el Forn (EF) and la Mina (LM) localities (Figure 2).
Units | Samples | Depth (m) | 10Be (at/g) | 26Al (at/g) | Minimum burial agea (Ma) | Denudation before burial (m/Ma) | Maximum burial ageb (Ma) |
II | LM-1-Ru | 9.12 | 71077±3580 | 32568±26558 | 0.87±0.08 | 31.09±2.98 | 1.20±0.11 |
II | LM-1-R | 9.12 | 157996±5122 | 64204±27546 | 1.09±0.06 | 11.83±0.64 | 1.26±0.07 |
I-II | LM-2-R | 7.87 | 71683±3341 | 187420±59827 | 2.05±0.66 | 16.52±5.33 | 3.87±1.25 |
II | EF-1-Ru | 5.90 | 40590±3327 | 251553±18129 | 0.24±0.03 | 76.79±8.38 | 0.93±0.1 |
II | EF-1-R | 5.90 | 86145±3651 | 37603±18501 | 0.97±0.06 | 24.15±1.57 | 1.53±0.1 |
II | EF-1-A | 5.90 | 84164±3426 | 35403±20277 | 1.05±0.07 | 23.74±1.67 | 1.68±0.12 |
II | EF-2-A | 6.10 | 94357±3911 | 39181±21855 | 1.07±0.07 | 20.78±1.44 | 1.60±0.11 |
I-II | EF-3-R | 6.70 | 74650±3201 | 22015±16369 | 1.80±0.15 | 18.12±1.55 | 3.45±0.3 |
I | EF-4-R | 7.30 | 74358±4031 | 18649±17236 | 2.14±0.23 | 15.18±1.63 | 4.41±0.47 |
I | EF-6-A | 7.60 | 7696±4003 | 20809±13573 | 1.98±0.17 | 15.92±1.33 | 3.58±0.3 |
I | EF-5-R | 8.20 | 20073±6381 | 38290±22720 | 2.60±0.18 | 3.92±0.26 | 3.22±0.22 |
La Mina sediment density = 1.52 g/cm3. El Forn sediment density = 1.46 g/cm3. The geographical parameters used for calculation are: latitude of 41.13587° for LM and 41.13475° for EF, an altitude of 50 m and a pressure of 1007 mbar. Neutronic production are 4.45 at.g−1.a−1 for 10Be and 29.40 at.g−1.a−1 for 26Al; slow muons production are 0.012 at.g−1.a−1 for 10Be and 0.861 at.g−1.a−1 for 26Al; and fast muons production are 0.039 at.g−1.a−1 for 10Be and 0.082 at.g−1.a−1 for 26Al [49].
In the “minimum burial age” model, it is assumed that the samples did not accumulate cosmogenic nuclides while buried (infinite burial depth).
In the “maximum burial age” model, it is assumed that the samples remained buried at their sampling depths and accumulated cosmogenic nuclides produced by muons. In this case, denudation rate is considered constant before and after burial (15±2 m/Ma). Burial age and denudation rate uncertainties (reported as 1σ) propagate the half-lives uncertainties.