Synchronous intracrystalline δ13C and δ18O differences in natural calcite crystals
Synchronous intracrystalline δ13C and δ18O differences in natural calcite crystals
复制标题
天然方解石晶体中同步晶内 δ13C 和 δ18O 差异
作者：
J. Dickson
摘要本文报道了两种方解石的新的交叉同位素数据。门迪普方解石在同步{213 4}和{011 4}扇区之间没有可检测到的δ 13 C和δ 18 O差异。诺丁汉方解石显示同步{404 ¥ 1}和{0001}扇区之间的δ 13 C差异为1.0‰，δ 18 O差异为0.5‰。现有的5种不同方解石的数据表明，交叉分馏的幅度是可变的;对δ 13 C的影响是对δ 18 O的两倍。所有五种天然方解石也显示出不稳定的同位素差异之间的等效同步扇区。部门间同位素分馏可能很普遍，但其原因和量化需要进一步的工作。同步晶内同位素的差异应容纳在同位素数据的解释，并应影响未来的采样策略。
Abstract New intersectorial isotope data are presented for two calcites. Mendip calcite shows no detectable δ13C and δ18O differences between synchronous {213¯4} and {011¯4} sectors. Nottingham calcite shows a δ13C difference of 1.0‰ and a δ18O difference of 0.5‰ between synchronous {404¯1} and {0001} sectors. Data now available for 5 different calcites show the magnitude of intersectorial fractionation is variable; the effect on δ13C is twice that on δ18O. All five natural calcites also show erratic isotopic differences between symmetrically-equivalent synchronous sectors. Intersectorial isotopic fractionation is probably widespread but its cause and quantification require further work. Synchronous intracrystalline isotopic differences should be accommodated in the interpretation of isotopic data and should influence future sampling strategy.