• The 1975 M7.2 Kalapana earthquake, which occurred on a fault patch under the entire Kilauea Summit and East Rift Zone area, was followed within hours by a short eruption at the summit of Kilauea. (hawaii247.com)
  • The researchers analyzed the chemical composition of crystals from Mount St. Helens and linked these data to seismic observations of the deadly 1980 Mount St. Helens eruption. (ruhr-uni-bochum.de)
  • False colour image of zoned orthopyroxene crystal used in forensic-style analysis of Mount St Helens 1980 eruption. (ruhr-uni-bochum.de)
  • A new stratigraphy for bimodal Oligocene flood volcanism that forms the volcanic plateau of northern Yemen is presented based on detailed field observations, petrography and geochemical correlations. (springer.com)
  • 1 km thick volcanic pile is divided into three phases of volcanism: a main basaltic stage (31 to 29.7 Ma), a main silicic stage (29.7 to 29.5 Ma), and a stage of upper bimodal volcanism (29.5 to 27.7 Ma). (springer.com)
  • The outer core is mostly Iron, but magmas are silicate liquids. (tulane.edu)
  • Temperatures of most magmas are in the range 700°C to 1300°C (or 1292°F to 2372°F), but very rare carbonatite melts may be as cool as 600°C, and komatiite melts may have been as hot as 1600°C. Most are silicate solutions. (phys.org)
  • In other work related to the issue of volcanic hazards associated with instability, Pamela de Groat-Nelson and colleagues at Arizona State University are researching silicic domes. (geotimes.org)
  • At depth in the Earth nearly all magmas contain gas dissolved in the liquid, but the gas forms a separate vapor phase when pressure is decreased as magma rises toward the surface of the Earth. (tulane.edu)
  • Rhyolitic magma -- SiO 2 65-75%, low in Fe, Mg, Ca, high in K, Na Gases in Magmas At depth in the Earth nearly all magmas contain gas dissolved in the liquid, but the gas forms a separate vapor phase when pressure is decreased as magma rises toward the surface of the Earth. (coursehero.com)
  • Environments of magma formation and compositions are commonly correlated. (phys.org)
  • Magma compositions may evolve after formation by fractional crystallization, contamination, and magma mixing. (phys.org)
  • The frosted and etched surfaces of many rough Rock Creek sapphires indicated that they are xenocrysts brought by magma carriers during volcanic eruptions. (gia.edu)
  • Mark Reid and colleagues also from the USGS incorporated these results into a new three-dimensional slope stability model to image the distribution of hydrothermally altered (weak) and fresh (strong) rock of the volcanic edifice. (geotimes.org)
  • Seismic activity had occurred in 1897-1898, 1933-1937, and again in 1966-1967, but the eruption that began on 18 July 1995 was the first since the 19th century in Montserrat. (wikipedia.org)
  • In this way, the researchers confirmed what has long been anticipated: a clear evidence of the correlation between crystal growth (fresh magma input) and volcanic seismicity. (ruhr-uni-bochum.de)
  • The time scales of magma ascent are difficult to observe directly and their investigation using indirect methods has received considerable attention. (geotimes.org)
  • At 11:27 pm local time on Monday 28 July 2008, an eruption began without any precursory activity. (wikipedia.org)
  • But the core is not likely to be the source of magmas because it does not have the right chemical composition. (tulane.edu)
  • They show how these data can be used to assess the degree of fractionation of the host magma and to calculate key trace element abundances and ratios. (eurekalert.org)
  • Since the rest of the earth is solid, in order for magmas to form, some part of the earth must get hot enough to melt the rocks present. (tulane.edu)
  • Diapirs also form in the earth's mantle when a sufficient mass of hot, less dense magma assembles. (wikipedia.org)
  • Diatremes are not usually associated with diapirs, as they are small-volume magmas which ascend by volatile plumes, not by density contrast with the surrounding mantle. (wikipedia.org)
  • Bachmann O, Dungan MA, Lipman PW (2002) The Fish Canyon magma body, San Juan volcanic field, Colorado: Rejuvenation and eruption of an upper crustal batholith. (springer.com)
  • Although eruption volumes decrease by an order of magnitude from the first stage to the last, eruption intervals within each phase remain broadly similar. (springer.com)