TABLE 4

INVENTORIES OF COSMOGENICALLY PRODUCED BERYLLIUM (7Be and 10Be)

7Be 10Be
Half-life 53.6 days 2.5 × 106 years
Production Rate (atoms·cm-2·s-1)

    Troposphere

    Total Atmosphere

Global Inventory



2.7 × 10-2

8.1 × 10-2

3.2 kg (107 PBq)



1.5 × 10-2

4.5 × 10-2

3.9 × 105 kg (as of 1967)

Distribution (%)

Stratosphere

    Troposphere

    Biosphere/land surface

    Mixed ocean layer

    Deep ocean layer

    Ocean sediments



60.0

11.0

8.0

20.0

0.2

0



0.00037

0.23

29.0

0.00057

0.001

70.7

Concentration

Stratosphere

Troposphere

Oceans



0.28 Bq/kg air

0.011 Bq/kg air

--



--

--

2 × 10-7 Bq/kg water

Method of Production      Spallation processes; Target nuclei 14N, 16O, 12C
Main Radiation Electron capture      555 keV

477 keV


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