What Is Dacite? About The Igneous Rock
DACITE – In this topic, we are going to know and learn about a volcanic felsic rock which is known as dacite.
As mentioned above, it is a felsic extrusive rock which is intermediate in composition between andesite and rhyolite. Dacite contains more quartz than andesite and more plagioclase than rhyolite, in which the plagioclase feldspars are often oligoclase, andesine or labradorite.
It is also composed of minerals such as biotite, hornblende, augite, and enstatite.
The rock is usually found akin with andesite, and forms lava flows, dikes, as well as massive intrusions in the centres of old volcanoes, in some cases. It is the volcanic counterpart of granodiorite.
It is also usually found in lava flows, lava domes, dikes, sills, and pyroclastic debris.
It varies in color but it is generally bluish-grey or pale grey. This volcanic rock is porphyritic in texture, which is usually found in volcanic rocks.
The rock can be used as an aggregate or fill, among other uses, in the construction and roading industries. However, the rock is not ideal for concrete aggregate due to high silica content, according to The University of Auckland.
READ ALSO: What Is Obsidian? About The Igneous Rock