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  2. Magma chamber - Wikipedia

    en.wikipedia.org/wiki/Magma_chamber

    Magma chambers above a subducting plate. Magma rises through cracks from beneath and across the crust because it is less dense than the surrounding rock. When the magma cannot find a path upwards it pools into a magma chamber. These chambers are commonly built up over time, [4] [5] by successive horizontal [6] or vertical [7] magma injections

  3. Volcanic and igneous plumbing systems - Wikipedia

    en.wikipedia.org/wiki/Volcanic_and_igneous...

    Magma emplacement can take place at any depth above the source rock. [4] Magma emplacement is primarily controlled by the internal forces of magma including buoyancy and magma pressure. [2] Magma pressure changes with depth as vertical stress is a function of the depth. [20] Another parameter of magma emplacement is the rate of magma supply. [2]

  4. Volcanic pipe - Wikipedia

    en.wikipedia.org/wiki/Volcanic_pipe

    As the body of magma rises toward the surface, the volatile compounds transform to gaseous phase as pressure is reduced with decreasing depth. This sudden expansion propels the magma upward at rapid speeds, resulting in a supersonic Plinian eruption. Mount Hypipamee Crater, Atherton Tableland, Queensland, Australia. This residue of a pipe is ...

  5. Strombolian eruption - Wikipedia

    en.wikipedia.org/wiki/Strombolian_eruption

    The most energetic Strombolian eruptions are sometimes termed "Violent Strombolian" by volcanologists. [2] Such eruptions are associated with higher magma gas content, leading to a turbulent churn flow regime in the conduit, producing stronger and much more frequent explosions.

  6. Igneous intrusion - Wikipedia

    en.wikipedia.org/wiki/Igneous_intrusion

    This produces magma that is less dense than its source rock. For example, a granitic magma, which is high in silica, has a density of 2.4 Mg/m 3, much less than the 2.8 Mg/m 3 of high-grade metamorphic rock. This gives the magma tremendous buoyancy, so that ascent of the magma is inevitable once enough magma has accumulated.

  7. Phreatomagmatic eruption - Wikipedia

    en.wikipedia.org/wiki/Phreatomagmatic_eruption

    A further control on the morphology and characteristics of a deposit is the water to magma ratio. It is considered that the products of phreatomagmatic eruptions are fine grained and poorly sorted where the magma/water ratio is high, but when there is a lower magma/water ratio the deposits may be coarser and better sorted. [4]

  8. Pillow lava - Wikipedia

    en.wikipedia.org/wiki/Pillow_lava

    They are created when magma reaches the surface but, as there is a large difference in temperature between the lava and the water, the surface of the emergent tongue cools very quickly, forming a skin. The tongue continues to lengthen and inflate with more lava, forming a lobe, until the pressure of the magma becomes sufficient to rupture the ...

  9. Phreatic eruption - Wikipedia

    en.wikipedia.org/wiki/Phreatic_eruption

    A scheme of a phreatic eruption: 1: water-vapor cloud, 2: magma conduit, 3: layers of lava and ash, 4: stratum, 5: water table, 6: explosion, 7: magma chamber Phreatic eruption at the summit of Mount St. Helens, Washington, in the spring of 1980