Strontium (Sr)

Atomic number: 38
Atomic weight: 87.62
Average concentration in ocean: 89 µmol/kg
Residence time: 5,100,000 years

Distribution in ocean
The Sr vertical profile has a slight surface depletion.  Plankton of the class Acantharia make shells of SrSO4, which produces the low surface concentration (data). 

Speciation
Strontium is present as Sr2+. 

Residence time
The strontium residence time is from Tracers in the Sea (Broecker, W. S. and Peng, T.-H., 1982.  Eldigo Press, Palisades, NY).  It was calculated from the global average river input.

Analysis
Strontium can be determined by graphite furnace atomic absorption spectrophotometry or mass spectrometry.

References & Notes