Phys.org August 19, 2024 Transitions in eruptive style during volcanic eruptions strongly depend on how easily gas and magma decouple during ascent. Stronger gas-melt coupling favors highly explosive eruptions, whereas weaker coupling promotes lava fountaining and lava flows. The mechanisms producing these transitions are still poorly understood because of a lack of direct observations of bubble dynamics under natural magmatic conditions. An international team of researchers (UK, Italy, France) combined x-ray radiography with a high-pressure/high-temperature apparatus to observe and quantify in real-time bubble growth and coalescence in basaltic magmas from 100 megapascals to surface. For low-viscosity magmas, bubbles coalesced and […]
Tag Archives: Magma
Scientists say sun’s influence penetrates into deep Earth
Phys.org July 23, 2024 Vanadium and scandium levels of arc magma served as key indicators in the geochemical models. By compiling global geochemical data from Cenozoic arc magma and olivine-hosted melt inclusions, researchers at the University of Arizona found a latitude-dependent redox distribution of arc magma with less oxidized magma in lower latitudes compared to those in higher latitudes. Based on their work the researchers proposed that such a latitude-dependent pattern in the arc mantle may be controlled by the variation in the redox state of subducted sediment, possibly related to a latitudinal variation in the primary production of phytoplankton, […]