A new measurement of Yellowstone’s underground magma reservoirs reveals they are fuller than expected. But this doesn’t mean Yellowstone is more likely to erupt than before, explains Robin George Andrews for The New York Times.
https://www.nytimes.com/2022/12/01/science/yellowstone-volcano-magma.html
“Hot spot tracks” like the volcanic features in Yellowstone are thought to be caused by giant plumes rising up from Earth’s mantle. In 2021 Robin George Andrews wrote for Quanta about the structure of the plumes arises from complex mantle dynamics.
https://www.quantamagazine.org/a-massive-subterranean-tree-is-moving-magma-to-earths-surface-20210915/
Lava tree molds are cavities or holes in the ground that mark where forests once stood in the path of an approaching lava flow. When lava flows through a forest, it swirls around tree trunks and quickly solidifies. Moisture in the wood and gas bubbles in the rocks form excellent insulation against instant incineration.
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The majority of granitic magmas are formed by melting near the base of the continents. The magmas slowly rise through the crust like great balloons. They solidify near the surface to form gigantic bodies of igneous rock called plutons, which are exposed later when uplift and erosion remove the overlying rock.
A body of intrusive igneous rock which crystallizes from magma cooling underneath the surface of the Earth is called a pluton. If the pluton is large, it may be called a batholith or a stock depending on the area exposed at the surface.
Batholith:
Its spectacular shape is characteristic of the vast igneous formations known as batholiths. A batholith is a very large mass of intrusive igneous rock that forms and cools deep in the Earth’s crust. An igneous rock is a type of rock formed through the cooling of lava or magma.
A pluton is an intrusion of magma that wells up from below the surface. Plutons can include dikes and xenoliths. A magmatic dike is simply a large slab of magmatic material that has intruded into another rock body. A xenolith is a piece of rock trapped in another type of rock.
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