HR: 1340h
AN: V13D-1588    [Abstracts]
TI: Re-evaluation for a geochemical significance of the fine structure in rare earth element pattern normalized by chondritic abundance: Pseudo-tetrad effect in geological materials
AU: * Lee, S
EM: sgl@kigam.re.kr
AF: Groundwater and Geothermal Resources Division, Korea Institute of Geoscience and Mineral Resources, 30 Gajeongdong, Yuseonggu, Daejeon, 305-350, Korea, Republic of
AU: Kim, K
EM: kkh@kigam.re.kr
AF: Gelological and Environmental Hazards Division, Korea Institute of Geoscience and Mineral Resources, 30 Gajeongdong, Yuseonggu, Daejeon, 305-350, Korea, Republic of
AU: Lee, S
EM: leesr@kigam.re.kr
AF: Gelology and Geoinformation Division, Korea Institute of Geoscience and Mineral Resources, 30 Gajeongdong, Yuseonggu, Daejeon, 305-350, Korea, Republic of
AB: Rare earth element (REE) distribution pattern in geological materials normalized by chondritic abundance is one of important geochemical tools for understanding their evolution history. However, sometimes, it arouses some disputes in interpreting of formation processes for rare earth element (REE) distribution pattern such as ¢®¡ÆREE tetrad effect¢®¡¾. For example, McLennan (1994) showed that tetrad curves in normalized REE patterns are commonly very subtle and proposed that the occurrence of tetrads might be attributed to analytical problems. However, later literatures (Lee et al., 1994; Monecke et al., 2002, 2007) show that the REE tetrad effect is not analytical artifact. Recently, we observed W-type tetrad effect from mafic dike reported by Son et al. (2007). However, in re-measuring the REE concentrations for the same samples, we could not observe the REE tetrad effect. This indicates that the fine structure in rare earth element pattern normalized by chondritic abundance, sometimes, might be produced from analytical procedure of a laboratory like the preceding by McLennan (1994). In this paper, we will discuss a possibility of pseudo-tetrad effect¢®¡¾ due to REE data acquisition process during analytical procedures. Our results indicate that, despite much analytical improvements, the existence of subtle tetrads is still difficult to prove.
DE: 1065 Major and trace element geochemistry
DE: 1099 General or miscellaneous
DE: 3699 General or miscellaneous
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2007 Fall Meeting