An analogous program exists in seawater, in which 44Ca/40Ca has a tendency to increase when the rate of elimination of Ca2+ by mineral precipitation exceeds the input of new calcium into your ocean. In 1997, Skulan and DePaolo presented the first proof of transform in seawater 44Ca/40Ca over geologic time, https://mariotkzpd.blogdomago.com/27574986/cad-drawings-in-irvine-no-further-a-mystery