Table AT7. Step-by-step layout for calculating concentrations of dissolved Li (ppb) and Si (ppm) in Hole 1274A at 42 mbsf.
BET SSA (cm2/g) 7,494


SSA in tube (cm2) 29,976


Nickel Mountain olivine is Fo83; molecular weight = 151.648
g of Si in 1 mol Fo83 = 0.185


g of Li in 1 mol Fo83 = 2.00 x 10–6


Rate of dissolution mol/cm2/s


pH 7.5 1.75 x 10–14


pH 9.5 3.5 x 10–15


Time (days) 12 36 237 709
Time (s) 1,036,800 3,110,400 20,476,800 61,257,600
mol olivine dissolved = rate (mol/cm2/s) x SSA in tube (cm2) x time (s)
g Fo83 dissolved = mol olivine dissolved x molecular weight of Fo83
g Li released = g Fo83 dissolved x g of Li in 1 g Fo83
g Si released = g Fo83 dissolved x g of Si in 1 g Fo 83
@ pH 7.5 12 days 36 days 237 days 709 days
mol Fo83 dissolved = 0.0005 0.0016 0.0107 0.0321
g Fo83 dissolved = 0.0825 0.2474 1.6290 4.8731
g Li released = 1.65 x 10–7 4.95 x 10–7 3.26 x 10–6 9.75 x 10–6
g Si released = 0.015 0.046 0.301 0.902
@ pH 9.5



mol Fo83 dissolved = 0.0001 0.0003 0.0021 0.0064
g Fo83 dissolved = 0.0165 0.0495 0.3258 0.9746
g Li released = 3.30 x 10–8 9.90 x 10–8 6.52 x 10–7 1.95 x 10–6
g Si released = 0.003 0.009 0.060 0.180

Note: SSA = specific surface area.