basaltic magma

geology

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June 23, 2026

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Basaltic magma is a type of molten rock that forms igneous rocks when it cools and solidifies. It is characterized by a low silica content and is rich in iron and magnesium. This magma is typically generated deep within the Earth's mantle, around 70 kilometers below the surface, and is associated with high temperatures, often around 1,200 °C (2,200 °F).123

Basaltic magma is a primary component of the Earth's oceanic crust and is predominant in non-explosive volcanic eruptions, producing flowing lava. It is also found in large-scale formations like flood basalts, which can cover vast areas and are found worldwide, including regions like the northwestern United States, India, and South America. While basaltic magma is generally less viscous than other types, its flow behavior, crystallization, and eruptive style are influenced by factors such as temperature, dissolved gases, and chemical composition.23456

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igneous rock
Origin of magmas
Basaltic magmas that form the oceanic crust of Earth are generated in the asthenosphere at a depth of about 70 kilometres. The mantle rocks located at depths from about 70 to 200 kilometres are believed to exist at temperatures slightly above their melting point, and…
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Basaltic magmas that form the oceanic crust of Earth are generated in the asthenosphere at a depth of about 70 kilometres. The mantle rocks located at depths from about 70 to 200 kilometres are believed to exist at temperatures slightly above their melting point, and…
Read More

plate tectonics
Supercontinent cycle
…hot, and vast volumes of basaltic magma pond beneath it, forcing it to arch up and crack. Magma invades the cracks, and the process of continental rifting, ultimately leading to seafloor spreading, begins. This model implies that supercontinents have built-in obsolescence and can exist only for so long before the…
Read More
…hot, and vast volumes of basaltic magma pond beneath it, forcing it to arch up and crack. Magma invades the cracks, and the process of continental rifting, ultimately leading to seafloor spreading, begins. This model implies that supercontinents have built-in obsolescence and can exist only for so long before the…
Read More

volcano
Subduction volcanoes
The rising subduction-zone magma is probably basaltic in composition and is formed by the partial melting of mantle rocks. As the rising magma moves slowly up through the continental crust of the overriding plate, however, two things may occur to increase significantly the silica content of the magma.…
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The rising subduction-zone magma is probably basaltic in composition and is formed by the partial melting of mantle rocks. As the rising magma moves slowly up through the continental crust of the overriding plate, however, two things may occur to increase significantly the silica content of the magma.…
Read More