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→Isotopic correlation
==Isotopic correlation==
==Isotopic correlation==
[[file:applied-paleontology_fig17-29.png|left|thumb|{{figure number|1}}. Copyright: Wright and Miller, 1993; courtesy American Geophysical Union. Time scale adapted from <ref name=ch17r12>Berggren, W., A., Kent, D., V., Flynn, J., J., 1985a, Paleogene geochronology and chronostratigraphy, in Snelling, N., J., ed., The Chronology of the Geological Record: Geological Society of London Memoir 10, p. 141–195.</ref><ref name=ch17r13>Berggren, W., A., Kent, D., and J.A. van Couvering, 1985b, Neogene geochronology and chronostratig- raphy, in N.J. Snelling, ed., The Chronology of the Geological Record: Geological Society of London Memoir 10, p. 211–260.</ref>.]]
[[file:applied-paleontology_fig17-29.png|thumb|{{figure number|1}}. Copyright: Wright and Miller, 1993; courtesy American Geophysical Union. Time scale adapted from Berggren et al.<ref name=ch17r12>Berggren, W., A., Kent, D., V., Flynn, J., J., 1985a, Paleogene geochronology and chronostratigraphy, in Snelling, N., J., ed., The Chronology of the Geological Record: Geological Society of London Memoir 10, p. 141–195.</ref><ref name=ch17r13>Berggren, W., A., Kent, D., and J.A. van Couvering, 1985b, Neogene geochronology and chronostratig- raphy, in N.J. Snelling, ed., The Chronology of the Geological Record: Geological Society of London Memoir 10, p. 211–260.</ref>]]
Comparison of curves representing isotopic values through time can provide a basis for regional or even worldwide correlations. Although biotic and diagenetic effects must be considered when evaluating and using isotopic data, isotopic techniques can significantly augment the resolution of existing biostratigraphic zonations and provide accurate correlations within basins. Two useful stable isotopic techniques involve measuring the ratios of isotopes of oxygen (<sup>18</sup>O/<sup>16</sup>O) and strontium (<sup>87</sup>Sr/<sup>86</sup>Sr).
Comparison of curves representing isotopic values through time can provide a basis for regional or even worldwide correlations. Although biotic and diagenetic effects must be considered when evaluating and using isotopic data, isotopic techniques can significantly augment the resolution of existing biostratigraphic zonations and provide accurate correlations within basins. Two useful stable isotopic techniques involve measuring the ratios of isotopes of oxygen (<sup>18</sup>O/<sup>16</sup>O) and strontium (<sup>87</sup>Sr/<sup>86</sup>Sr).