Tag: Basalt

Basalt ( /bəˈsɔːlt/, /ˈbæsɔːlt/, or /ˈbeɪsɔːlt/) is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey. According to the official definition, basalt is defined as an aphanitic igneous rock that contains, by volume, less than 20% quartz and less than 10% feldspathoid and where at least 65% of the feldspar is in the form of plagioclase.
On Earth, most basalt magmas have formed by decompression melting of the mantle. Basalt has also formed on Earth’s Moon, Mars, Venus, and even on the asteroid Vesta. Source rocks for the partial melts probably include both peridotite and pyroxenite (e.g., Sobolev et al., 2007). The crustal portions of oceanic tectonic plates are composed predominantly of basalt, produced from upwelling mantle below ocean ridges.
The term basalt is at…

Basalt CO Skateboard Lessons!

Learn Skateboarding in a 7 Day Lesson

Skateboarding is a recreational activity, an art form, or a method of transportation. Skateboarding has been designed and influenced by many skateboarders throughout the years. A 2002 report by American Sports Data found that there are 18.5 million skaters in the world. 85 percent of skaters…