The argument that temperature change and biological change during the Ordovician are correlated and, perhaps, causally related has been advanced by measurements of δ18Ophos values on conodont apatite, a phase more resistant to diagenetic alteration than carbonates. However, the available conodontδ18Ophos records are discontinuous and are biased towards North American samples. To test the generality of global patterns and to expand the geographical range of studied regions, we document δ18Ophos values from conodont apatite as well as δ13C and δ18Ocalcite values from bulk carbonate from New South Wales, Australia. New results span most of the Ordovician and include the first Late Ordovician phosphate δ18O values from the Australian continent. The data from New South Wales show an ∼1. 5‰VSMOW increase in δ18Ophos values during the Early and Middle Ordovician. This pattern matches previously documented trends from Laurentia and central Australia, but values in New South Wales are consistently ∼2. 5‰VSMOW lower than those from other regions. We attribute these low δ18Ophos values to local paleoceanographic effects on the seawater δ18O value.
|Number of pages||6|
|Issue number||Online Supplement|
|Publication status||Published - 2015|
|Event||International Conference on the Ordovician System (12th : 2015) - Harrisonburg, United States|
Duration: 8 Jun 2015 → 11 Jun 2015
Conference number: 12th