(a) Not included in seawater Ca-isotope curve, 2smean > 0.4 per mil.(b) Ages for Hole 1218A according to Pälike et al. (2006); age determinations for Hole 574C using the position of datum levels in Barron et al. (1985), with numerical ages adapted to the age model of Pälike et al. (2006) following Zachos et al. (2004).(c) Isotopic composition of seawater calculated using the following equation:d44/40Ca seawater = d44/40Ca barite + 2.01 per mil(d) 2smean = 2s/n0.5 calculated from repeated TIMS measurements of an individual sample.(e) n = number of TIMS analyses on a single sample; numbers in parentheses were sample runs analyzed at the USGS.(f) Duplicate samples processed from barite dissolution and cation separation to TIMS analysis.(g) Extremely low value was not plotted, but must be investigated further before being dismissed.