Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Andesitic magma

Petrologic determination of ascent rates for the 1995—1997 Soutnere hiUs volcano andesitic magma. Geophys. Res. Lett. 25, 3673-3676. [Pg.1452]

Murphy M. D., Sparks R. S. J., Barclay J., Carroll M. R., and Brewer T. S. (2000) Remobilization of andesite magma by intrusion of mafic magma at the Souffiere Hills Volcano, Montserrat, West Indies. J. Petrol. 41, 21-42. [Pg.1454]

Furukawa Y. and Tatsumi Y. (1999) Melting of a subducting slab and production of high-Mg andesite magmas unusual magmatism in SW Japan at 13 approximately 15 Ma. Geophys. Res. Lett. 26(15), 2271-2274. [Pg.1908]

Kushiro I. (1974) Melting of hydrous upper mantle and possible generation of andesitic magma an approach from synthetic systems. Earth Planet. Sci. Lett. 22, 294-299. [Pg.1910]

Weaver, B.L. andTarney, J., 1982. Andesitic magma-tism and continental growth. In Thorpe R.S. (ed) Andesites. Wiley, London, pp. 639-61. [Pg.271]

Anatexis of subducted oceanic lithosphere generates relatively uraniferous magmas. Continental andesites range from 0.5 to 1.0 ppm uranium, whereas island-arc andesites range from 0.2 to 0.4 ppm. Enrichment in continental andesites is probably due to continental crustal contamination. Fractionation of andesitic magmas can separate uranium, alkaline-earth... [Pg.90]

Aimna-Miyasaka M, Nakagawa M (2003) Evolution of Deeper Basaltic and Shallower Andesitic Magmas during the AD 1469-1983 Eruptions of Miyake-JLma Volcano, Izu-Mariana Arc Inferences from Temporal Variations of Mineral Compositions in Crystal-Clots, J. Petrology 44 2113-2138. [Pg.1057]

Th/232xh) ratios have been recalcnlated at the time of eraption. (c) Data from a Sonfriere andesite (St Vincent, after Heath et al. 1998) interpreted as an old magma (minerals + melt). (contined on facing page)... [Pg.146]

Gauthier P-J, Condomines M, Hammouda T (1999) An experimental investigation of radon diffusion in an anhydrous andesitic melt at atmospheric pressure Implications for radon degassing from empting magmas. Geochim Cosmochim Acta 63 645-656... [Pg.171]

Poll S, Schmidt MW (1995) H2O transport and release in subduction zones experimental constraints on basaltic and andesitic systems. J Geophys Res 100 22,299-22,314 Pyle DM, Ivanovich M, Sparks RSJ (1988) Magma-cumulate mixing identified by U-Th disequilibrium dating. Nature 331 157-159... [Pg.308]

Sigmarsson O, Chmeleff J, Morris J, Lopez-Escobar L (2002) Origin of Tla- °Th disequilibria in arc lavas from southern Chile and magma transfer time. Earth Planet Sci Lett 196 189-196 Sisson TW, Layne GD (1993) H2O in basalt and basaltic andesite inclusions from four subduction-related volcanoes. Earth Planet Sci Lett 117 619-635... [Pg.308]

Villemant B, Boudon G, Komorowski JC (1996) U-series disequilibrium in arc magmas induced by water-magma interaction. Earth Planet Sci Lett 140 259-267 Volpe AM, Hammond PE (1991) U- °Th- Ra disequilibrium in young Mt. St. Helens rocks time constraint for magma formation and crystallization. Earth Planet Sci Lett 107 475-486 Volpe A M (1992) U- °Th- Ra disequilibrium in young Mt. Shasta andesites and dacites. J Volcanol Geotherm Res 53 227-238... [Pg.309]

The Earth s crust and, indeed, the crusts of all differentiated bodies, are enriched in incompatible elements relative to their mantles. This reflects the partial melting of mantle material and extraction and transport of the basaltic melt to the surface. On Earth, further partial melting of the basaltic crust in the presence of water produces magma compositions even richer in silica (andesite and granite), which form the bulk of the continental crust. Because other differentiated bodies are effectively dry, this second level of differentiation did not occur. [Pg.218]

The volcanoes in the Campania Province, Pontine Islands and Vulture are composed of a wide variety of magma types. Silica undersaturated ultrapo-tassic volcanism is restricted to Somma-Vesuvio, whereas mildly undersaturated to oversaturated potassic rocks occur at Campi Flegrei, Ischia, Procida and Ventotene. In the latter two islands, low potassium compositions close to calc-alkaline basalts are found among lavas and lithic ejecta. Pliocene calc-alkaline rocks are found as rhyolites at Ponza and as basalts and basaltic andesites beneath the Campanian Plain. At Vulture, volcanism is highly enriched in both Na and K, a composition that is distinct from any other volcano in the Italian peninsula. [Pg.162]

The Vulture, Campania and Pontine volcanoes are characterised by magmas that vary from calc-alkaline to ultrapotassic compositions. Calc-alkaline rocks occur as rhyolites at onza and as basalt to basaltic andesites beneath the Campanian plain. Both these occurrences are older than the potassic and ultrapotassic magmas, indicating an overall time-related increase in potassium on a regional basis. [Pg.167]

See other pages where Andesitic magma is mentioned: [Pg.134]    [Pg.143]    [Pg.42]    [Pg.45]    [Pg.560]    [Pg.180]    [Pg.359]    [Pg.297]    [Pg.327]    [Pg.1392]    [Pg.1616]    [Pg.1863]    [Pg.1870]    [Pg.1871]    [Pg.1874]    [Pg.1904]    [Pg.134]    [Pg.143]    [Pg.42]    [Pg.45]    [Pg.560]    [Pg.180]    [Pg.359]    [Pg.297]    [Pg.327]    [Pg.1392]    [Pg.1616]    [Pg.1863]    [Pg.1870]    [Pg.1871]    [Pg.1874]    [Pg.1904]    [Pg.313]    [Pg.433]    [Pg.142]    [Pg.145]    [Pg.155]    [Pg.168]    [Pg.168]    [Pg.298]    [Pg.299]    [Pg.306]    [Pg.265]    [Pg.115]    [Pg.117]    [Pg.167]    [Pg.120]    [Pg.123]    [Pg.506]    [Pg.37]    [Pg.183]   
See also in sourсe #XX -- [ Pg.42 ]



SEARCH



Andesite

© 2024 chempedia.info