# name
Comparative study of the classification of plutonic and volcanic rocks using the normative Q' (F')-ANOR and chemical SiO2-100·CaO/(CaO+K2O) diagrams

# metadata.dc.description.abstract[].value
To obtain a classiﬁcation of igneous rocks, compatible with the QAPF classiﬁcation, in the absence of modal analyses, a chemical diagram using the same discriminating elements as the Q'(F')-ANOR normative diagram has been proposed. These elements, Si, Ca and K, are essential constituents of quartz, feldspars and feldspathoids. The different proportions between these minerals are the basis of the QAPF modal classiﬁcation but also those of the normative classiﬁcation Q'(F')-ANOR. The chemical diagram SiO2100·CaO/(CaO+K2O) uses these same elements but with the important difference that they are treated as independent variables. This characteristic allows igneous rocks to be classiﬁed with a nomenclature equivalent to that obtained by modal analyses, using only Si, Ca and K analytical data. The plotting of a set of representative plutonic and volcanic rocks reveals a remarkable concordance between both diagrams. However, some discrepancies and overlaps occur in the subsaturated ﬁelds due to the inability of the method to determine whether the lower silica content is due to the presence of olivine or feldspathoids. The samples selected belong to igneous series from diverse geotectonic areas , thus helping to evaluate the results in a global context.

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Articles publicats en revistes (Educació Lingüística, Científica i Matemàtica)

# metadata.dc.title[].value
Comparative study of the classification of plutonic and volcanic rocks using the normative Q' (F')-ANOR and chemical SiO2-100·CaO/(CaO+K2O) diagrams