Exploratory compositional data analysis. (English) Zbl 1158.86333

Buccianti, A. (ed.) et al., Compositional data analysis in the geosciences: from theory to practice. London: The Geological Society Publishing House (ISBN 978-1-86239-205-2/hbk). Geological Society Special Publication 264, 161-174 (2006).
Summary: This paper presents the first steps that should be performed whenever the study of a compositional dataset is initiated. Centre, variation matrix and total variance of a compositional dataset are introduced. In addition the biplots are also introduced as a powerful tool to analyse and discover special features related to subcompositions. The exploratory methodology is applied to a dataset consisting of the major, minor and trace elements composition of soil samples from several places in Tuscany (Italy). The structure of the data, collected from three different known country rocks of ophiolitic nature (basic and ultrabasic rocks), represent an interesting case study for experimenting on new methodologies of statistical investigation and for pointing out differences related to parental chemistry and mineralogy as well as the nature of processes to be related to the subsequent evolution.
For the entire collection see [Zbl 1155.86002].


86A32 Geostatistics