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 …

An aphanitic (fine-grained) igneous rock is classified as basalt when its QAPF fraction is composed of less than 10% feldspathoid and less than 20% quartz, and plagioclase makes up …

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 …

Basalt is the most common composition of lava rocks that cool from magma, liquid rock that rises from the deep Earth at volcanoes. Today basalt is forming at many active rifts, including …

Basalt is significant in geology as it is the primary rock type that forms from the solidification of lava flows, playing a crucial role in the formation of other igneous rocks. It is generated at mid …

A fine-grained basic igneous rock. It is composed chiefly of calcium-rich plagioclase feldspar and pyroxene; other minerals present may be olivine, magnetite, and apatite. Basalt is the …

Type Igneous Rock Texture Aphanitic (Fine-grained) Origin Extrusive/Volcanic Chemical Composition Mafic Color Black Mineral Composition Calcium Plagioclase, Pyroxene, Olivine …

BASALT definition: a fine-grained dark basic igneous rock consisting of plagioclase feldspar , a pyroxene ,... | Meaning, pronunciation, translations and examples in American English

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 …

Dec 20, 2025 · Basalt, extrusive igneous (volcanic) rock that is low in silica content, dark in color, and comparatively rich in iron and magnesium. Basalts may be broadly classified on a …