Skeletal oxygen and carbon isotope signatures of hermatipic, cold-water and precious corals

Abstract

Recently, deep-sea precious corals attract much attention because climatic information and the history of deep-ocean circulation changes could be obtained from those corals with huge geographic and depth ranges in the ocean. Oxygen and carbon isotopic ratios as well as elemental compositions incorporated in the calcite skeleton of these corals have been proposed as a method for obtaining information from intermediate and deep-water environments. In the present study, we analyzed stable isotope ratios and elemental composition, together with radiocarbon (14C) dating, of three specimens of deep-sea precious corals from NW Pacific. Also, we discussed the differences in isotopic characteristics among precious, cold-water and hermatipic corals from the viewpoint as paleo-environmental archives.