@article{fdi:010044171,
  title = {{C}haracterization of various stages of calcitization in {P}orites sp corals from uplifted reefs - {C}ase studies from {N}ew {C}aledonia, {V}anuatu, and {F}utuna ({S}outh-{W}est {P}acific)},
  author = {{R}abier, {C}. and {A}nguy, {Y}. and {C}abioch, {G}uy and {G}enthon, {P}ierre},
  editor = {},
  language = {{ENG}},
  abstract = {{T}his study focuses on the processes of calcitization under meteoric conditions based on observations and analyses of a series of subaerial fossil corals of the genus {P}ontes collected from emerged {H}olocene and {P}leistocene reefs in the {P}acific {O}cean. {W}e can establish two types of low-magnesian calcite ({LMC}) precipitates according to their textural characteristics after their transformation from the initial aragonitic skeleton to the calcitized corals. {I}n the first variety ({LMCI}), the calcite contains remnants of the original exoskeleton structure (in situ insoluble organic tissues. pieces of aragonite needles) while in the second variety ({LMC}2) - filling the primary inter-skeletal macro-pores - such relicts are not present. {S}uch textural segregation is faithfully reflected in the elemental data on some parts of calcitized corals. {LMC}1 is characterized by {M}g2+, {S}r2+, and {M}n2+ compositions inherited from the aragonite precursor, indicating a formation in a semi-closed infra-skeleton diagenetic environment in disequilibrium with the meteoric bulk aquifer water. {LMC}2 has a chemistry indicative of equilibrium with ambient bulk meteoric water. {T}hese chemical characteristics can be likened to a two-fold mechanism: a fine-scale process - neomorphism typified by the concomitant dissolution of intra-fabric aragonite and re-precipitation of the {LMCI} resulting from the 'biogenic' skeleton and marine waters, followed by the cementation of the inter-fabric macro-voids by an allochthonous subaerial and meteoric {LMC}2. {I}n the other parts of calcitized corals, {LMCI} and {LMC}2 have similar trace element contents in {M}gt(2+) and {S}r2+. {T}he chemical data are consistent with formation by partial skeletal dissolution followed eventually by cementation of primary voids ({LMC}2) and secondary voids ({LMC}1) by calcite in equilibrium with meteoric bulk aquifer water. {T}hese two mechanisms of the calcitization of skeletal aragonite mainly differ in the space and time length-scales of the intervening transport step, and are commonly found juxtaposed in the same thin section. {T}aking into account such a heterogeneity is a real challenge for the development of predictive models assessing the effects of diagenetic products on paleoclimatic reconstructions.},
  keywords = {{C}alcite cementation ; {F}ossil corals ; {G}eochemistry ; {M}eteoric diagenesis ; {M}icro-structure ; {A}ragonite neomorphism},
  booktitle = {},
  journal = {{S}edimentary {G}eology},
  volume = {211},
  numero = {3-4},
  pages = {73--86},
  ISSN = {0037-0738},
  year = {2008},
  DOI = {10.1016/j.sedgeo.2008.08.005},
  URL = {https://www.documentation.ird.fr/hor/fdi:010044171},
}