The Role of Volatiles in the Genesis Evolution and Eruption of Arc Magmas
The cycling of volatiles, particularly the major chemical species H2O, CO2 and SO2 (and the input of trace halogen, lithium and mercury-bearing fluxes), within a subduction zone system is a fundamental factor in understanding the petrogenesis, transport, storage and ultimate eruption of arc magmas. Volatile components significantly contribute to the flux of subducting slab materials into the mantle wedge and are responsible for melt / magma generation, exerting a key influence on the mineral phases produced within the overriding crust. The rate and scope of volatile degassing during melt generation, storage and decompression significantly affect the rheology of the magmas produced. These factors strongly influence the style of eruption and therefore the potential environmental impact of explosive arc volcanism and inform any subsequent risk assessment and hazard mitigation strategies. This Geological Society Special Publication presents recent research insights into the role of volatiles on magmatic processes within subduction zone environments.
Introduced with an overview article outlining the research context, the volume presents 11 papers organised into three fully-indexed thematic sections: aspects of volatile tracing from the subducting slab to the overriding crust (including slab devolatilisation, the composition and detection of generated primary melts and the effect of volatiles on magma differentiation and ascent), the role of volatiles in subvolcanic processes and eruption triggering, and the behaviour of volatiles in magmatic-hydrothermal systems, ore deposits and volcanic degassing are examined. Research topics cover both ancient and young / active subduction zones, ranging from metamorphic petrological work on exhumed subduction-accretion complexes, geophysical studies of the mantle wedge, remote sensing of volcanic gases and include several diverse geochemical approaches (including micro-analytical techniques on erupted rocks).
The volume provides an excellent synthesis of the current research within this important area. All papers are well-written and edited, with clear and appropriate figures, photographs and data-tables.
Directly relevant to both pure and applied research geoscientists within the field, it is also a comprehensive data source for those scientists / engineers attempting risk evaluation and hazard mitigation strategy development within areas susceptible to explosive arc volcanism. A recommended read.
Reviewed by Mark Griffin
THE ROLE OF VOLATILES IN THE GENESIS, EVOLUTION AND ERUPTION OF ARC MAGMAS by G. F. Zellmer, M. Edmonds and S. M. Straub (editors). Geological Society of London Special Publication No 410. 2015. Geological Society of London. ISBN 978-1-86239-689-0. Hbk. 292pp. ISSN 0305-8719. List Price: £100.00, www.geolsoc.org.uk.