Abstract
A potash trachyte (containing 13% K2O) crops out within the Malvernian (Pre-cambrian) calc-alkaline igneous complex. The chemical composition is similar to that of minor intrusions in areas of alkaline igneous activity. An origin by partial melting of biotite-rich basement rocks is proposed.
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Thorpe, R.S. A Potash-rich trachyte from the Pre-Cambrian of England. Contr. Mineral. and Petrol. 31, 115–120 (1971). https://doi.org/10.1007/BF00373454
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DOI: https://doi.org/10.1007/BF00373454