Richard A. Herd

University of East Anglia

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Jenni Barclay

University of East Anglia

Marie Edmonds

University of Cambridge

B. Voight

Pennsylvania State University

G. S. Mattioli

The University of Texas at Arlington

R. S. J. Sparks

University of Bristol

Ralf Gertisser

Keele University

Katie Preece

Swansea University

G. E. Norton

British Geological Survey

Derek Elsworth

Pennsylvania State University

S. R. Young

RELX Group (United States)

Cooperative Institutions

Montserrat Volcano Observatory

University of Cambridge

University of Bristol

United States Geological Survey

Centre National de la Recherche Scientifique

British Geological Survey

University of East Anglia

Pennsylvania State University

University of the West Indies

University of Oxford

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Chapter 18 Characterization of mafic enclaves in the erupted products of Soufrière Hills Volcano, Montserrat, 2009 to 2010

Geological Society London Memoirs (2014)

Melissa Plail Jenni Barclay Madeleine C. S. Humphreys Marie Edmonds Richard A. Herd

Abstract Lavas from the current eruption of the Soufrière Hills Volcano (SHV), Montserrat exhibit evidence for magma mingling, related to the intrusion of mafic magma at depth. We present detailed field, petrological, textural and geochemical descriptions of mafic enclaves in andesite erupted during 2009–2010, and subdivide the enclaves into three distinct types: type A are mafic, glassy with chilled margins and few inherited phenocrysts; type B are more evolved with high inherited phenocryst content and little glass, and are interpreted as significantly hybridized; type C are composite, with a mafic interior (type A) and a hybrid exterior (type B). All enclaves define tight linear compositional trends, interpreted as mixing between a mafic end member (type A) and host andesite. Enclave glasses are rhyolitic, owing to extensive crystallization during quenching. Type A quench crystallization is driven by rapid thermal equilibration during injection into the andesite. Conversely, type B enclaves form in a hybridized melt layer, which ponded near the base of the chamber and cooled more slowly. Vesiculation near the mafic–silicic interface resulted in disruption of the hybridized layer and the formation of the type B enclaves. The composite enclaves represent an interface between types A and B, suggesting multiple episodes of mafic injection.

10.1144/m39.18

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Citations (35)

Developing a simplified geographical information system approach to dilute lahar modelling for rapid hazard assessment

Bulletin of Volcanology (2013)

Amii R. Darnell Jeffrey Phillips Jenni Barclay Richard A. Herd Andrew Lovett

Lahar

Elevation (ballistics)

Flow routing

10.1007/s00445-013-0713-6

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Citations (20)

Magma storage, transport and degassing during the 2008–10 summit eruption at Kīlauea Volcano, Hawai‘i

Geochimica et Cosmochimica Acta (2013)

Marie Edmonds I. Sides Donald A. Swanson C. A. Werner Robert Martin

The 2008–current summit eruption at Kīlauea Volcano, Hawai'i offers a unique opportunity to test models of degassing and magma plumbing and to improve our understanding of the volatile budget. The aim of this work was to test the hypothesis that gases emitted from a summit lava lake will be rich in carbon dioxide (CO2) and similar to those measured during the persistent lava lake activity in the early 20th century at Kīlauea Volcano (Gerlach and Graeber, 1985). We measured the sulfur dioxide (SO2) and CO2 concentrations in the gas plume from Halema'uma'u using electrochemical and non-dispersive infrared sensors during April 2009. We also analysed olivine-hosted melt inclusions from tephra erupted in 2008 and 2010 for major, trace and volatile elements. The gas and melt data are both consistent with the equilibration of a relatively evolved magma batch at depths of 1.2–2.0 km beneath Halema'uma'u prior to the current degassing activity. The differences in the volatile concentrations between the melt inclusions and matrix glasses are consistent with the observed gas composition. The degassing of sulfur and halogen gases from the melt requires low pressures and hence we invoke convection to bring the magma close to the surface to degas, before sinking back into the conduit. The fluxes of gases (900 and 80 t/d SO2 and CO2 respectively) are used to estimate magma fluxes (1.2–3.4 m3/s) to the surface for April 2009. The observation of minimal loss of hydrogen from the melt inclusions implies a rapid rise rate (less than a few hours), which constrains the conduit radius to 1–2 m. The inferred conduit radius is much narrower than the lava lake at the surface, implying a flared geometry. The melt inclusion data suggest that there is a progressive decrease in melt volatile concentrations with time during 2008–2010, consistent with convection, degassing and mixing in a closed, or semi-closed magma system. The degassing regime of the current summit lava lake activity is not similar to that observed in the early 20th century; instead the gases are extensively depleted in CO2.

Melt inclusions

Volcanic Gases

10.1016/j.gca.2013.05.038

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Citations (53)

Halogen degassing during ascent and eruption of water-poor basaltic magma

Chemical Geology (2008)

Marie Edmonds Terrence M. Gerlach Richard A. Herd

Melt inclusions

Volcanic Gases

Magma chamber

10.1016/j.chemgeo.2008.09.022

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Citations (49)

Ground deformation measurements at the Soufriere Hills Volcano, Montserrat: II: Rapid static GPS measurements June 1996–June 1997

Geophysical Research Letters (1998)

J. B. Shepherd Richard A. Herd Paul Jackson Robert B. Watts

We describe measurements of ground deformation around the erupting Soufriere Hills volcano made between June 1996 and June 1997 using Rapid Static GPS. The measurements define a lateral displacement field which is approximately radially symmetrical about the growing dome. No significant sustained vertical displacements have been identified. Radial displacements have generally increased steadily during this period of observation. The rate of displacement decreases from 43 cm per year at a distance of 0.6 km from the centre of the dome to about 1 cm/year at a distance of 3.8 km. Strains within one km of the dome itself are greater than 10 −3 . The rate of variation of strain with distance indicates a causative centre of pressure at a depth of not greater than 750 meters below the summit of the dome

Dome (geology)

Summit

10.1029/98gl01655

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Citations (27)

SO2 emissions from Soufrière Hills Volcano and their relationship to conduit permeability, hydrothermal interaction and degassing regime

Journal of Volcanology and Geothermal Research (2003)

Marie Edmonds Clive Oppenheimer David M. Pyle Richard A. Herd Gary M. Thompson

Electrical conduit

Dome (geology)

Magma chamber

10.1016/s0377-0273(03)00041-6

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Citations (202)

An application-driven approach to terrain model construction

International Journal of Geographical Information Science (2010)

Amii R. Darnell Andrew Lovett Jenni Barclay Richard A. Herd

Terrain is a surface phenomenon that is measured, modelled, and mapped. However, it is continuously variable and must be simulated by points or mathematical equations that are inherently approximations. The error induced by digitally represented terrain can propagate to surface derivatives and geographical information science (GIS) applications where topography is considered. This can lead to uncertainty in model predictions and the use of data that are unfit for the application to which they are intended. This article outlines the problem of uncertainty in terrain representation and demonstrates the consequences for volcanic mudflow modelling. The response of a simple least-cost single flow algorithm to input parameters was investigated in order to assess output variation from the different sources of input variation. Elevation error was modelled with a probability density function (PDF) and propagated through stochastic simulation (Monte Carlo). Such combined uncertainty and sensitivity analyses enabled a qualitative judgement of the relative significance of elevation error on the flow model prediction. Different methods for terrain model construction were considered and show that supplementing global positioning system (GPS) measurements with information from field notes and reconnaissance photographs greatly improved the model performance and reduced the uncertainty. It is concluded that in terms of validity of model results, there is no substitute for constructing an elevation model that is informed by the terrain.

Elevation (ballistics)

Propagation of uncertainty

Representation

Stochastic modelling

10.1080/13658810903318889

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Citations (8)

Metals, petroleum hydrocarbons and organochlorines in inshore sediments and waters of Mombasa, Kenya

Marine Pollution Bulletin (1997)

Thomas M. Williams John Rees A. Ferguson Richard A. Herd K.K. Kairu

10.1016/s0025-326x(97)00043-x

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Citations (11)

Seismo-acoustics, VLP and ULP signals, and other comparisons of surface broadband and CALIPSO borehole data at Soufriere Hills Volcano, Montserrat, B.W.I.

AGUFM (2003)

D. Hidayat B. Voight G. S. Mattioli S. R. Young A. T. Linde

Source

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Chapter 11 Volcano geodesy at the Soufrière Hills Volcano, Montserrat: a review

Geological Society London Memoirs (2014)

Henry Odbert G. Ryan G. S. Mattioli Stefanie Hautmann Joachim Gottsmann

Abstract Geodetic surveying is a core volcano monitoring technique. Measurements of how the crust deforms can give valuable insight into the mechanisms and processes that drive an eruption, and the way in which they change. Various geodetic observables, including ground deformation and gravity changes, have been recorded on Montserrat throughout the eruption. Instrumentation and surveying networks used to make such measurements have evolved significantly since 1995, providing increasingly accurate and robust observations. The detailed research that has been facilitated by these rich geodetic datasets has illuminated many aspects of the Soufrière Hills Volcano (SHV) and demonstrated eruptive mechanisms that are relevant to the study of other volcanoes. We have compiled a history of the geodetic study of the eruption on Montserrat, detailing the development of surveying techniques, network design and data processing since 1995. We then underline some of the key geodetic observations and review some of the most significant research that has contributed to our understanding of this volcanic system. Finally, we apply a series of typical deformation inversion models to deformation observations, and discuss the parameter sensitivity of such modelling approaches and how confidently they can be applied to identify the characteristics of the mechanisms feeding the eruption.

10.1144/m39.11

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Citations (22)