Reservoir

Be, kg

Be, kg/yr

Be concentration

Mantle¹

2 x 10¹⁷

    MORB source

0.02-0.03 ppm*

    Intraplate source

0.08-0.1 ppm*

    "Primitive mantle"

~ 0.066 ppm*

Oceans¹

2.5 x 10¹¹

0.2 pg/g (seawater)

River inputs²

4 x 10⁴

1.2 pg/g (river water)

Aerosol inputs³

7-24 x 10⁴ (?)

Marine hydrothermal inputs⁴

1-5 x 10⁴

0.1-0.4 ng/g (endmember vent fluids)

Marine Sediments⁵

6 x 10¹⁴

1.5 ppm

Continents¹

3 x 10¹⁶

1.5 ppm

Additions to ocean crust via MORB magmatism⁵

9.9 x 10⁶

0.3 ppm (MORB)

Sediment Subduction⁵

1.5 x 10⁶

1.5 ppm (sediments)

Additions to the continents via arc magmatism⁵

1.6 x 10⁶

0.5 ppm (Arc basalts)