Block of Tonalite, Amphibolite, Migmatite, and Granodiorite
by Metwally Hamza, Research Assistant in the field of geology with international published research papers. Academically interested in cosmic geology & planetary sciences. Geology fiend who likes to take photos of nature & geological features, Egypt
- Block of four different rocks;
- Tonalite is an igneous, plutonic, intrusive, felsic rock. With phaneritic texture. Feldspar is present as plagioclase (oligoclase or andesine). With 10% or less alkali feldspar. Quartz is present as more than 20% of the rock. The accessory minerals may be amphibole and pyroxene.
- Amphibolite is a metamorphic rock that contains amphibole, hornblende, and actinolite, as well as plagioclase. With little or no quartz. It is typically dark-colored and dense, with a schistose or flaky structure.
- Migmatite is a composite rock found in medium and high-grade metamorphic environments.
- Granodiorite is an intrusive, igneous rock, similar to granite, but containing more plagioclase feldspar than orthoclase feldspar. With a phaneritic texture.
Metwally Hamza (distributed via imaggeo.egu.eu)