Figure F15. Concentrations of (A) Mg²⁺, (B) Ca²⁺, (C) Sr²⁺, (D) Li⁺, and (E) H₄SiO₄⁰. Note the large decrease in the concentration of Ca ²⁺ and Mg²⁺ in the upper 300 mbsf and the rapid increase in Sr²⁺ between 200 and 300 mbsf.