Exploration geochemistry—Distribution of elements and recognition of anomalies

G. J. S. Govett1, W. D. Goodfellow1, R. P. Chapman2, C. Y. Chork1
1Department of Geology, University of New Brunswick, Fredericton, Canada
2Exploration Division, Shell Canada Ltd., Calgary, Canada

Tóm tắt

The exploration geochemist faces a serious problem in reconciling theoretical statistics with the empirical distribution of elements in materials in the earth's crust. The results of computer-simulation experiments being conducted by the Exploration Geochemistry Group at the University of New Brunswick illustrate some of the problems of the relation between frequency distributions and spatial distributions of elements and raise some interesting questions about sampling patterns and physical size of samples. Most importantly, the simulation experiments and empirical examples support the contention that attempts to make an assumption of normality more efficient by performing log transformations on positively skewed data may defeat the purpose of statistical analysis for exploration work. New developments in computer-data presentation and interpretation, including population sorting and classification, illustrate the increasing use of the computer in exploration geochemistry.

Tài liệu tham khảo

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