calc-alkalic series
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The calc-alkaline series is a classification of igneous rocks, primarily volcanic and hypabyssal types, distinguished by their chemical composition. These rocks are characterized by a higher alumina content and a broader silica range compared to tholeiitic series rocks. They are commonly found in the volcanic regions of continental margins, particularly along convergent plate boundaries.1
The calc-alkaline series includes rocks such as basalt, andesite, dacite, and rhyolite. These rocks are typically silica-saturated and may contain normative minerals like orthopyroxene and quartz. Their formation is often linked to the melting of subducted oceanic slabs and overlying mantle material, with water playing a significant role in their evolution. This series is considered a principal mechanism for the growth of the Earth's continental crust throughout geologic time.12
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igneous rockClassification of volcanic and hypabyssal rocks… and the iron-poor group called calc-alkalic. The former group is most commonly found along the oceanic ridges and on the ocean floor; the latter group is characteristic of the volcanic regions of the continental margins (convergent, or destructive, plate boundaries; see below Forms of occurrence: Distribution of igneous rocks on…
Read More… and the iron-poor group called calc-alkalic. The former group is most commonly found along the oceanic ridges and on the ocean floor; the latter group is characteristic of the volcanic regions of the continental margins (convergent, or destructive, plate boundaries; see below Forms of occurrence: Distribution of igneous rocks on…
Read More- igneous rockConvergent plate boundaries
…a tholeiitic series and a calc-alkalic series sometimes erupt from the same volcano. The former is characterized by lower magnesium, potassium, nickel, chromium, uranium, and thorium and a higher iron:magnesium ratio. Mineralogically, the tholeiitic series characteristically contains pigeonite (a low-calcium monoclinic pyroxene) in the groundmass of the basalts and andesites.…
Read More…a tholeiitic series and a calc-alkalic series sometimes erupt from the same volcano. The former is characterized by lower magnesium, potassium, nickel, chromium, uranium, and thorium and a higher iron:magnesium ratio. Mineralogically, the tholeiitic series characteristically contains pigeonite (a low-calcium monoclinic pyroxene) in the groundmass of the basalts and andesites.…
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