A research on the tectonic setting discrimination of andesite based on the data mining

<p indent="0mm">The accurate identification of the tectonic settings of igneous rocks plays a key role for revealing geological history and the evolution of plate tectonics. Traditionally, the andesite was considered as an indicator of arc setting, however, it has diverse tectonic setting attributes suggested by big data researches. This paper has comprehensively organized data of Cenozoic mid-ocean ridge andesites (MORA), ocean island andesites (OIA), oceanic arc andesites (OAA), continental arc andesites (CAA), and continental rift andesites (CRA) from the GEOROC and PetDB databases. Based on the results of data dimensionality reduction and visualization, by employing the data mining, we have step by step constructed three sets of andesite tectonic environment discrimination diagrams, including the oceanic-continental andesite discrimination diagrams, the MORA-OIA-OAA discrimination diagrams, and the CAA-CRA discrimination diagrams, and have validated the effectiveness of these diagrams by using data of Mesozoic samples with certain tectonic setting attributes. The study indicates that Large Ion Lithophile Elements (LILE) and Light Rare Earth Elements (LREE) are the primary fingerprints of different mantle resources of andesites, while Pb of andesites, to some extent, can be used to distinguish their oceanic and continental settings. These elements played key roles in those discrimination diagrams. The comprehensive analysis combined with multiple geological evidences will enhance the objectivity and reliability of the tectonic setting discrimination results.