Mg/Ca Thermometry in Coral Skeletons
The magnesium-to-calcium (Mg/Ca) ratio of coral skeletons from Ishigaki Island, Ryukyu Islands, Japan, closely tracked sea surface temperature (SST) over an 8-year period. Measurements were made with the fast technique of inductively coupled plasma-atomic emission spectrometry. The variation of the coral Mg/Ca ratio with SST change is about four times that of the current, widely used coral strontium-to-calcium ratio. The temporal and geographic variation of the seawater Mg2+/Ca2+ ratio probably has little influence on coral Mg/Ca variation. Results indicate that the coral Mg/Ca ratio has the potential to provide fast, precise, high-resolution proxies for past tropical SSTs.
Mitsuguchi
T
T. Mitsuguchi, E. Matsumoto, O. Abe, Institute for Hydrospheric-Atmospheric Sciences, Nagoya University, Nagoya 464-01, Japan. T. Uchida, Nagoya Institute of Technology, Nagoya 466, Japan. P. J. Isdale, Australian Institute of Marine Science, Private Mail Bag 3, Townsville MC, Queensland 4810, Australia.
Matsumoto
E
Abe
O
Uchida
T
Isdale
PJ