What are basalt rocks?
Basalt is a hard, black volcanic rock with less than about 52 weight percent silica (SiO2). Because of basalt’s low silica content, it has a low viscosity (resistance to flow). Therefore, basaltic lava can flow quickly and easily move >20 km from a vent.
What is basalt short answer?
Basalt is a common extrusive volcanic rock, which is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet.
What is a description of basalt?
basalt, extrusive igneous (volcanic) rock that is low in silica content, dark in colour, and comparatively rich in iron and magnesium. Basaltic lavas are frequently spongy or pumiceous; the steam cavities become filled with secondary minerals such as calcite, chlorite, and zeolites.
How do you identify a basalt rock?
Basalt appears black or grayish-black, sometimes with a greenish or reddish crust. Feel its texture. Basalt consists of a fine and even-grain. The dense rock has no crystals or minerals discernible to the naked eye.
What is basalt rock made up of?
igneous
Basalts are common aphanitic igneous extrusive (volcanic) rocks. Basalts are composed of minute grains of plagioclase feldspar (generally labradorite), pyroxene, olivine, biotite, hornblende and <20% quartz. Nepheline or leucite may associate or proxy the feldspar giving rise to verities with special names.
What are basaltic igneous rocks?
Basalt (UK: /ˈbæs. ɔːlt, -əlt/; US: /bəˈsɔːlt, ˈbeɪˌsɔːlt/) is an aphanitic extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of all volcanic rock on Earth is basalt.
What is the purpose of basalt?
What is Basalt used for? Basalt is mainly used for structural building materials such as bricks, tiles, foundations and sculptures, as well as within stonewalls for thermal purposes and rail tracks. It can also be seen when looking at the moon as darker area which were formed from ancient lava flows.
How is basalt rock formed?
Basalts are formed by the rapid cooling of basaltic lava, equivalent to gabbro-norite magma, from interior of the crust and exposed at or very close to the surface of Earth. These basalt flows are quite thick and extensive, in which gas cavities are almost absent.
What is basalt rock used for?
What 5 minerals are commonly found in basalt?
Basalts are common aphanitic igneous extrusive (volcanic) rocks. Basalts are composed of minute grains of plagioclase feldspar (generally labradorite), pyroxene, olivine, biotite, hornblende and <20% quartz.
What is made of basalt rock?
Basalt is used for a wide variety of purposes. It is most commonly crushed for use as an aggregate in construction projects. Crushed basalt is used for road base, concrete aggregate, asphalt pavement aggregate, railroad ballast, filter stone in drain fields, and may other purposes.