%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Fallick, A. E.
%A Giuliani, Gaston
%A Rigaudier, T.
%A Boyce, A. J.
%A Pham, V. L.
%A Pardieu, V.
%T Remarkably uniform oxygen isotope systematics for co-existing pairs of gem-spinel and calcite in marble, with special reference to Vietnamese deposits
%D 2019
%L fdi:010075174
%G ENG
%J Comptes Rendus Geoscience
%@ 1631-0713
%K Marble deposits ; Asia ; East Africa ; Spinel-calcite pair ; Oxygen isotope ; fractionation ; Temperature of formation
%K VIET NAM ; TANZANIE ; NEPAL ; MYANMAR ; TADJIKISTAN ; PAKISTAN ; KENYA
%M ISI:000458134400004
%N 1
%P 27-36
%R 10.1016/j.crte.2018.11.008
%U https://www.documentation.ird.fr/hor/fdi:010075174
%> https://www.documentation.ird.fr/intranet/publi/2019/02/010075174.pdf
%V 351
%W Horizon (IRD)
%X Oxygen isotope systematics for co-existing pairs of gem-spinel and calcite in marble from Vietnam and other worldwide deposits have been determined in order to characterize the O-isotope fractionation between calcite and spinel. In Vietnam, the Delta O-18(cc-sp) (= 3.7 + 0.1 parts per thousand for six samples from the An Phu and Cong Troi deposits) is remarkably constant. The combination of these data with those obtained on calcite-spinel pairs of Paigutan (Nepal, n = 2), Ipanko (Tanzania, n = 1), and Mogok (Myanmar, = 2) are also consistent with an overall Delta O-18(cc-sp) of 3.6 + 0.3 parts per thousand for all the spinel samples (n = 11). The straight line correlation delta O-18(cc) = 0.96 delta O-18(sp) + 4.4 is excellent despite their worldwide geographic spread. The increment method of calculating oxygen isotope fractionation gave a geologically unreasonable temperature of formation for both minerals at 1374 degrees C when compared to temperatures obtained by mineral assemblage equilibrium of these marble type deposits, between 610 and 750 degrees C. The constant Delta O-18(cc-sp) reflects a constant temperature for this amphibolite facies assemblage, whose current best estimate is calculated at 620 + 40 degrees C, but unquantified uncertainties remain.
%$ 064