Figure F5. Late Cretaceous age-depth plots for sequences at Bass River (top) and Ancora (bottom). Solid black circles = Sr isotopic ages computed using the regressions (Age = 39104.339163 - 87Sr/86Sr x 55154.82511), applicable from 73.5 to 86.0 Ma and (Age = 31908.531372 - 87Sr/86Sr x 44984.801888), applicable from 65 to 73.5 Ma with ±1-m.y. error bars, blue circles = diagenetically altered samples, red = conservative age models, green = alternate age models. Horizontal olive-green lines indicate sequence boundaries. Blue triangles = CC nannofossil zones, x = planktonic foraminiferal age estimates. Blue blocks at bottom = time represented in each borehole (after Miller et al., unpubl. data).

Figure F5. Late Cretaceous age-depth plots for sequences at Bass River (top) and Ancora (bottom). Solid black circles = Sr isotopic ages computed using the regressions (Age = 39104.339163 - ⁸⁷Sr/⁸⁶Sr x 55154.82511), applicable from 73.5 to 86.0 Ma and (Age = 31908.531372 - ⁸⁷Sr/⁸⁶Sr x 44984.801888), applicable from 65 to 73.5 Ma with ±1-m.y. error bars, blue circles = diagenetically altered samples, red = conservative age models, green = alternate age models. Horizontal olive-green lines indicate sequence boundaries. Blue triangles = CC nannofossil zones, x = planktonic foraminiferal age estimates. Blue blocks at bottom = time represented in each borehole (after Miller et al., unpubl. data).