Felsic magma
Dome complexes typically erupt andesite to rhyolite magma, which is characterized by high viscosity. This viscosity leads to the formation of steep-sided volcanic domes, as the magma doesn't flow easily and tends to pile up near the vent. The eruptions can be explosive due to the buildup of gas pressure within the viscous magma. Consequently, dome complexes often exhibit both dome-building eruptions and pyroclastic flows.
Extrusive igneous rocks
Volcanoes primarily produce igneous rocks when magma erupts and cools. If the magma cools and solidifies beneath the Earth's surface, it forms intrusive igneous rocks, such as granite. If the magma erupts onto the surface as lava and cools quickly, it forms extrusive igneous rocks, such as basalt. The specific type of rock depends on the composition of the magma and the cooling conditions.
Mount Rainier primarily erupts andesitic magma, which is a type of intermediate magma that is thicker and more viscous than basaltic magma. Andesitic magma often leads to explosive eruptions due to its high gas content and tendency to trap pressure.
The type of underground magma formation that is usually dome-shaped is called a "laccolith." Laccoliths form when magma intrudes between layers of rock and causes the overlying strata to bulge upward, creating a dome-like structure. This occurs typically in sedimentary rock layers, resulting in a rounded, uplifted formation that can sometimes be seen at the surface.
Dome complexes typically erupt andesite to rhyolite magma, which is characterized by high viscosity. This viscosity leads to the formation of steep-sided volcanic domes, as the magma doesn't flow easily and tends to pile up near the vent. The eruptions can be explosive due to the buildup of gas pressure within the viscous magma. Consequently, dome complexes often exhibit both dome-building eruptions and pyroclastic flows.
Mount Pinatubo primarily erupts dacitic magma.
Cinder cone volcanoes are formed by basaltic magma.
The magma that erupts at Mount Pinatubo is mainly dacitic in composition, which is a type of intermediate magma that is rich in silica. This type of magma typically leads to explosive eruptions due to its high viscosity and gas content.
The magma type for a lava dome is typically viscous and silica-rich. This type of magma often leads to slower, more explosive eruptions that result in the gradual buildup of a dome-shaped feature composed of solidified lava.
Extrusive igneous rocks
Volcanic mountains are formed when magma rises to the Earth's surface and erupts. This magma cools and solidifies, building up layers of volcanic rock over time to form a mountain.
Volcanoes primarily produce igneous rocks when magma erupts and cools. If the magma cools and solidifies beneath the Earth's surface, it forms intrusive igneous rocks, such as granite. If the magma erupts onto the surface as lava and cools quickly, it forms extrusive igneous rocks, such as basalt. The specific type of rock depends on the composition of the magma and the cooling conditions.
Mount Rainier primarily erupts andesitic magma, which is a type of intermediate magma that is thicker and more viscous than basaltic magma. Andesitic magma often leads to explosive eruptions due to its high gas content and tendency to trap pressure.
extrusive igneous rock
The type of magma you are referring to is called viscous magma. It is rich in silica and other minerals, making it thick and sticky. As a result, it does not flow easily and tends to form domes or plugs when it erupts.
The type of underground magma formation that is usually dome-shaped is called a "laccolith." Laccoliths form when magma intrudes between layers of rock and causes the overlying strata to bulge upward, creating a dome-like structure. This occurs typically in sedimentary rock layers, resulting in a rounded, uplifted formation that can sometimes be seen at the surface.