An introduction to magma dynamics

Abstract

A variety of methods have been employed to decipher magmatic systems, including geophysical, petrological, textural and geochemical approaches, and these elucidate a large variety of characteristics of different plumbing systems and magmatic differentiation processes. A common theme to the papers presented in this book is the observation of transport of small volume magma batches with a relatively high frequency, as opposed to less frequent transport of larger magma volumes that would require storage in large crustal reservoirs for long periods of time. The implications of this observation are discussed in the context of a possible tectonic control on crustal magma dynamics.

Spatio-temporal evolution of a dispersed magmatic system and its implications for volcano growth, Jeju Island Volcanic Field, Korea

“…Further, we discuss the implications of our model for other intraplate volcanic areas and volcanic edifice building and briefly compare it to the stable magmatic conduit systems established beneath typical andesitic stratovolcanoes (Annen et al, 2006;Turner et al, 2011;Zellmer and Annen, 2008). We present new major and trace element and Sr-Nd-Pb chemical data from both surface samples and three deep cores (400-500m) penetrating the entire lava succession in the central part of Jeju Island.…”

“…Our data suggest that individual magma batches on Jeju evolved independently. This is different from arc-type andesitic volcanoes, where magmatic evolution involves one or a series of magma reservoirs that are repeatedly replenished, and feed eruptions through a stable central conduit, to form a composite edifice with conical morphology (Devine et al, 2003;Watanabe et al, 2006;Zellmer and Annen, 2008). The site of magma evolution in such volcanic systems can also be a complex network of dykes and sills (Price et al, 2010).…”

Genesis of the post-caldera eastern Upper Basin Member rhyolites, Yellowstone, WY: from volcanic stratigraphy, geochemistry, and radiogenic isotope modeling

“…Washburn volcanics are present in the Tuff of Uncle Tom's Trail (Christiansen 2001). Finally, Basin and Range tectonics extends through the park and is present along much of the Snake River-Yellowstone Track, though volcanic rocks associated with the track are not generally faulted (Leeman et al 2008). …”

Geochemical evidence for mixing between fluids exsolved at different depths in the magmatic system of Mt Etna (Italy)

“…Instead, the results from various approaches have revealed intricate systems of dikes, sills, and small chambers with irregular shapes that extend upward through the crust (Preston, 2001;Dawson et al, 2004;Marsh, 2004;Thomson, 2004;Cartwright and Hansen, 2006;Zellmer and Annen, 2008;Paulatto et al, 2010). The geometries of these bodies will clearly control the degree of hydraulic continuity and connectivity, and they somewhat hamper simple magma migration through the entire plumbing system.…”