High resolution rare-earth elements analyses of natural apatite and its application in geo-sciences: Combined micro-PIXE, quantitative CL spectroscopy and electron spin resonance analyses
D. Habermann et al., High resolution rare-earth elements analyses of natural apatite and its application in geo-sciences: Combined micro-PIXE, quantitative CL spectroscopy and electron spin resonance analyses, NUCL INST B, 161, 2000, pp. 846-851
The rare-earth element (REE) distribution in natural apatite is analysed by
micro-PIXE, cathodoluminescence (CL) microscopy and spectroscopy and elect
ron spin resonance (ESR) spectroscopy. The micro-PIXE analyses of an apatit
e crystal from Cerro de Mercado (Mexico) and the summary of 20 analyses of
six francolite (conodonts of Triassic age) samples indicate that most of th
e REEs are enriched ill apatite and francolite comparative to average shale
standard (NASC). The: analyses of fossil francolite revealing the REE-dist
ribution not to be in balance with the REE-distribution of seawater and fis
h bone debris. Strong inhomogenous lateral REE-distribution in fossil conod
ont material is shown by CL-mapping and most probably not being a vital eff
ect. Therefore. the resulting REE-signal from fossil francolite is the sum
of vital and post-mortem incorporation. The necessary charge compensation f
or the substitution of divalent Ca by trivalent REE being done by different
kind of electron defects and defect ions. (C) 2000 Elsevier Science B.V. A
ll rights reserved.