Ion microprobe assessment of the heterogeneity of Mg/Ca, Sr/Ca and Mn/Ca ratios in Pecten maximus and Mytilus edulis (bivalvia) shell calcite precipitated at constant temperature.
Clarke, Leon J. Kennedy, H.A. Richardson, C.A. Freitas, P.S.
Clarke, Leon J.
Kennedy, H.A.
Richardson, C.A.
Freitas, P.S.
An error occurred retrieving the object's statistics
Publication Date
2009
End of Embargo
Supervisor
Rights
Peer-Reviewed
Yes
Open Access status
closedAccess
Accepted for publication
Institution
Department
Awarded
Embargo end date
Collections
Additional title
Abstract
Small-scale heterogeneity of biogenic carbonate
elemental composition can be a significant source of error in
the accurate use of element/Ca ratios as geochemical proxies.
In this study ion microprobe (SIMS) profiles showed significant
small-scale variability of Mg/Ca, Sr/Ca and Mn/Ca
ratios in new shell calcite of the marine bivalves Pecten
maximus and Mytilus edulis that was precipitated during a
constant-temperature culturing experiment. Elevated Mg/Ca,
Sr/Ca and Mn/Ca ratios were found to be associated with the
deposition of elaborate shell features, i.e. a shell surface stria
in P. maximus and surface shell disturbance marks in both
species, the latter a common occurrence in bivalve shells. In
both species the observed small-scale elemental heterogeneity
most likely was not controlled by variable transport of
ions to the extra-pallial fluid, but by factors such as the influence
of shell organic content and/or crystal size and orientation,
the latter reflecting conditions at the shell crystalsolution
interface. In the mid and innermost regions of the
P. maximus shell the lack of significant small-scale variation
of Mg/Ca ratios, which is consistent with growth at constant
temperature, suggest a potential application as a palaeotemperature
proxy. Cross-growth band element/Ca ratio profiles
in the interior of bivalve shells may provide more promising
palaeo-environmental tools than sampling from the outer
region of bivalve shells.
Version
No full-text in the repository
Citation
Freitas, P. S., Clarke, L. J., Kennedy, H. and Richardson, C. A. (2009). Ion microprobe assessment of the heterogeneity of Mg/Ca, Sr/Ca and Mn/Ca ratios in Pecten maximus and Mytilus edulis (bivalvia) shell calcite precipitated at constant temperature. Biogeosciences. Vol. 6, pp. 1209-1227.
Link to publisher’s version
Link to published version
Link to Version of Record
Type
Article