Bulletin of the Geological Society of Malaysia, Volume 13, Dec. 1980, pp. 87 – 92
1Nuclear Science Unit, Universiti Kebangsaan Malaysia, Kuala Lumpur
2Department of Geology, University of Malaya, Kuala Lumpur
3Department of Physics, Universiti Kebangsaan Malaysia, Kuala Lumpur
Abstract: The REE abundances in five dolerite dykes (olivine tholeiite to quartz tholeiite) from Kuantan have been determined by instrumental (non-destructive) neutron activation analysis using reactor irradiation and high-resolution gamma-ray spectroscopy. The analytical procedures followed in this work are discussed.
A total of nine rare earths (La, Ce, Nd, Sm, Eu, Gd, Tb, Yb and Lu) have been measured. The dykes show fractionated REE patterns with chondrite-normalised values ranging from about 34 to 105 for La and from about 8 to 11 for Yb. The concentrations of individual elements as well as the ΣREE increase systematically with increasing differentiation. The more evolved rocks show positive Eu anomaly. The variations in REE abundances are compatible with a crystal fractionation (clinopyroxene and olivine) model of evolution interpreted from petrography and major element chemistry.