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  1. 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 …

  2. 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 …

  3. Basalt – Formation, Properties, Characteristics & Earth’s Most Common ...

    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, …

  4. 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 …

  5. 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.

  6. USGS: Volcano Hazards Program Glossary - Basalt

    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 …

  7. 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).

  8. 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 …

  9. Basalt - Michigan Technological University

    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 Iceland, the East …

  10. Basalt Properties, Composition and Formation | Earth Know

    Apr 10, 2024 · Basalt is a massive, dense, fine-grained, dark-colored volcanic rock with mainly calcic plagioclase, augite, and other minor minerals.