Trondhjemite

Trondhjemite is a leucocratic (light-colored) intrusive igneous rock. It is a tonalite variety with high albite and low anorthite and orthoclase content. Trondhjemites are sometimes known as plagiogranites.

Additional recommended knowledge

Essential Laboratory Skills Guide

Guide to balance cleaning: 8 simple steps

Weighing the right way

Trondhjemite is common in Archean terranes occurring in conjunction with tonalite and granodiorite as the TTG (tonalite-trondhjemite-granodiorite) orto-gneiss suite. Trondhjemite dikes also commonly form part of the sheeted dike complex of an ophiolite.

References

• Best, Myron G. (2002) Igneous and Metamorphic Petrology, Blackwell Publishing, 2nd ed. ISBN 1-4051-0588-7