Ourbak Timothée, Corrège Thierry, Malaizé B., Le Cornec Florence, Charlier K., Peypouquet J. P. (2006). A high-resolution investigation of temperature, salinity, and upwelling activity proxies in corals - art. no. Q03013. Geochemistry Geophysics Geosystems, 7, p. NIL_95-NIL_107. ISSN 1525-2027.
Titre du document
A high-resolution investigation of temperature, salinity, and upwelling activity proxies in corals - art. no. Q03013
Ourbak Timothée, Corrège Thierry, Malaizé B., Le Cornec Florence, Charlier K., Peypouquet J. P.
Source
Geochemistry Geophysics Geosystems, 2006,
7, p. NIL_95-NIL_107 ISSN 1525-2027
We present a high-resolution study of five geochemical components of a New Caledonia coral core. Minor and trace elements (Sr/Ca, U/Ca, Mg/Ca, Ba/Ca), together with oxygen isotopes (delta O-18), were investigated at near-fortnightly resolution. Geochemical measurements were compared to sea surface temperature (SSTTSG) and salinity (SSSTSG) recorded by a thermosalinograph (TSG) located less than 10 m from the coral. Results show that Sr/Ca, Mg/Ca, and delta O-18 are temperature-dependent ( correlation coefficient to local SSTTSG between 0.74 and 0.84). Their robustness as SST tracers is tested against a satellite-based data set for a 4 year validation period. U/Ca has a more complex behavior and appears to be linked to both SSTTSG and SSSTSG, despite relatively small local SSS variations. For the first time this salinity-related imprint is quantified in a U/Ca coralline ratio. In addition to SST and SSS tracers, Ba/Ca measurements provide a possible way to investigate upwelling activity occurrences.
