
Basalt - Wikipedia
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 at least 65% of its …
Basalt: Igneous Rock - Pictures, Definition, Uses & More
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 in …
Basalt – Formation, Properties, Characteristics
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 magma, …
Basalt | Definition, Properties, & Facts | Britannica
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 chemical and …
Basalt: Composition, Properties, Types, Uses – Geology In
Basalt is defined as a fine-grained, dark-colored igneous rock composed mainly of plagioclase and pyroxene minerals, with or without olivine. It is formed from the rapid cooling of basaltic lava exposed …
A Guide to Basalt: A Common, Fine-grained, Dark-Colored Volcanic Rock
Aug 17, 2023 · Basalt is a common and widely used, fine-grained, dark-colored mafic volcanic rock. It has mainly calcic plagioclase feldspar and augite.
Basalt Rock | Composition, Textures and Geological Role
Dec 14, 2012 · Basalt is a very common dark-colored volcanic rock composed of calcic plagioclase (usually labradorite), clinopyroxene (augite) and iron ore (titaniferous magnetite). Basalt may also …
BASALT Definition & Meaning - Merriam-Webster
The meaning of BASALT is a dark gray to black dense to fine-grained igneous rock that consists of basic plagioclase, augite, and usually magnetite.
Basalt - Rockhounding Wiki
Basalt is a dark-colored, fine-grained igneous rock that forms from the rapid cooling of mafic lava. It is the most common extrusive rock on Earth, making up most of the ocean floor and many continental …
Basalt Definition - Intro to Geology Key Term | Fiveable
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 composed of …