Basalt is a dark-colored, fine-grained, igneous rock composed mainly of plagioclase and pyroxene minerals. It most commonly forms as an extrusive rock, such as a lava flow, but can also form …

Basalt is often porphyritic, containing larger crystals (phenocrysts) that formed before the extrusion event that brought the magma to the surface, embedded in a finer-grained matrix.

Apr 10, 2018 · Basalt is the most abundant volcanic rock on Earth, covering more than 90% of the ocean floor and large continental regions shaped by ancient lava flows. It forms when mafic …

Dec 20, 2025 · Some basalts are quite glassy (tachylytes), and many are very fine-grained and compact. It is more usual, however, for them to exhibit porphyritic structure, with larger crystals …

When they form long, straight columns, these are called colonnade. When they have more irregular shapes that look like they’ve been pushed or morphed, it’s called entablature. Basalt …

Dec 14, 2012 · Basalt is the original constituent of the crust from which almost all other rock types have evolved. Basalt forms when mantle rocks (peridotite) start to melt. Rocks melt …

Jan 4, 2024 · Basalt is a fine-grained, extrusive igneous rock predominantly formed from the rapid cooling of mafic lava, which is low in silica and rich in magnesium and iron. In geology, …

Basalt is a fine-grained, dark-colored igneous rock that forms from the rapid cooling of lava at or near the Earth's surface. It is the most common type of volcanic rock and is primarily …

Apr 24, 2025 · In this informative video, we’ll take a closer look at basalt, an essential component of the Earth’s geology. We’ll define what basalt is and explore how it forms through volcanic …

Basalt is a dark-colored, fine-grained igneous rock that forms from the rapid cooling of lava. It's one of the most common rock types on Earth, making up most of the ocean floor and many …