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Papers by Richard Herd

Research paper thumbnail of Timescales of magma ascent and degassing and the role of crustal assimilation at Merapi volcano (2006–2010), Indonesia: Constraints from uranium-series and radiogenic isotopic compositions

Geochimica et Cosmochimica Acta, Feb 1, 2018

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Research paper thumbnail of SedCas_Volcano: Simulating decadal patterns of lahar hazard and sediment transfer following volcanic disturbance in the Belham River Valley, Montserrat&#160

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Research paper thumbnail of Chapter 16 Pre-eruptive vapour and its role in controlling eruption style and longevity at Soufrière Hills Volcano

Geological Society, London, Memoirs, 2014

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Research paper thumbnail of Transitions between explosive and effusive phases during the cataclysmic 2010 eruption of Merapi volcano, Java, Indonesia

Bulletin of Volcanology, Jul 18, 2016

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Research paper thumbnail of Catastrophic lava dome failure at Soufrière Hills Volcano, Montserrat, 12–13 July 2003

Journal of Volcanology and Geothermal Research, Dec 1, 2005

... July (Table 1) and presumably was caused by the large volume of pyroclastic flow material dis... more ... July (Table 1) and presumably was caused by the large volume of pyroclastic flow material displacing ... the shoreline was eroded by the tsunami, indicating that the surge was emplaced before the ... to have been generated during the most intense stages of the lava dome unloading ...

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Research paper thumbnail of Field measurements of the rheological and thermal properties of lavas from the East Rift Zone, Hawaii

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Research paper thumbnail of Little and often or once in a while with a bang? Quantifying lahar hazard on Montserrat

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Research paper thumbnail of An application-driven approach to terrain model construction

International Journal of Geographical Information Science, Jun 21, 2010

Terrain is a surface phenomenon that is measured, modelled, and mapped. However, it is continuous... more 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

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Research paper thumbnail of Hazard implications of small-scale edifice instability and sector collapse: a case history from Soufrière Hills Volcano, Montserrat

Geological Society, London, Memoirs, 2002

During the 1995 to 1998 phase of dome growth at Soufrière Hills Volcano on Montserrat, we documen... more During the 1995 to 1998 phase of dome growth at Soufrière Hills Volcano on Montserrat, we documented instability of the steep southern rim of English's Crater, known as Galway's Wall. The horseshoe-shaped…

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Research paper thumbnail of Volatile and light lithophile trace element geochemistry of the 2010 and other recent eruptions of Merapi volcano, Java, Indonesia:NERC Scientific Facilities and Technology Ion Microprobe Facility – 2012 Annual Science Report

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Research paper thumbnail of Insights into Magmatic Degassing at Merapi Volcano, Indonesia from Uranium-Series Disequilibria in Recently Erupted Volcanic Rocks

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Research paper thumbnail of Rapid eruptive transitions from low to high intensity explosions and effusive activity: insights from textural analysis of a small-volume trachytic eruption, Ascension Island, South Atlantic

Bulletin of Volcanology, 2021

Proximal deposits of small-volume trachytic eruptions are an under-studied record of eruption dyn... more Proximal deposits of small-volume trachytic eruptions are an under-studied record of eruption dynamics despite being common across a range of settings. The 59 ± 4 ka Echo Canyon deposits, Ascension Island, resulted from a small-volume explosive-effusive trachytic eruption. Variations in juvenile clast texture reveal changes in ascent dynamics and transitions in eruption style. Five dominant textural types are identified within the pumice lapilli population. Early Strombolian-Vulcanian eruption phases are typified by macro- and micro-vesicular equant clast types. Sheared clasts are most abundant at the eruption peak, transitioning to dense clasts in later phases due to shear-induced coalescence, outgassing and vesicle collapse. Melt densification and outgassing via tuffisite veins increased plume density, contributing to partial column collapse and the explosive-effusive transition. Bulk vesicularity distributions indicate a shift in dominant fragmentation mechanism during the erupti...

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Research paper thumbnail of Mafic enclaves record syn-eruptive basalt intrusion and mixing

Earth and Planetary Science Letters, 2018

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Research paper thumbnail of The Ongoing Eruption in Montserrat

Science, 1997

... the new techniques developed are making this eruption one of historic importance to ... the c... more ... the new techniques developed are making this eruption one of historic importance to ... the continuing activity, but the social and economic pressure building on officials ... Murray. , eds (1995) Monitoring Active Volcanoes: Strategies, Procedures and Techniques (University College ...

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Research paper thumbnail of Ground deformation at Soufrière Hills Volcano, Montserrat during 1998–2000 measured by radar interferometry and GPS

Journal of Volcanology and Geothermal Research, 2006

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Research paper thumbnail of Mafic enclave diversity at the Soufrière Hills Volcano, Montserrat

ABSTRACT The andesitic Soufrière Hills Volcano, Montserrat has been active since 1995, with five ... more ABSTRACT The andesitic Soufrière Hills Volcano, Montserrat has been active since 1995, with five phases of dome growth to date. Mafic enclaves are ubiquitous, and supply of mafic magma is interpreted as the main driver for the current eruption. Recent (Phases IV to V) activity has changed from longer periods of dome growth to shorter more intensive episodes. This is coincident with an increase in the abundance and heterogeneity of mafic enclaves, implying that the changes in activity may reflect differences within the magmatic system. The intense Phase V episode lasted ~18 weeks, culminating in the energetic collapse of Feb. 11th 2010. Within these deposits three distinct mafic enclave types have been identified using textural and geochemical variations: (A) Weakly porphyritic basaltic enclaves; with chilled margins and inherited phenocryst proportions of < 8%. (B) Medium to highly porphyritic basaltic-andesite enclaves; with diffuse margins and inherited phenocryst proportions of 16-25%. (C) Composite; a mixture of types A and B indicating two-stage mixing. Textural and petrological variations also includes differences in: vesicularity, modal mineral assemblages, glass abundance, groundmass size and distribution. Inherited phenocrysts show petrological and geochemical characteristics consistent with late stage heating and inheritance from the andesite. Bulk XRF analyses of Phase V enclaves shows a wide compositional range of 48-58wt% SiO2. An observed SiO2 compositional gap between the mafic enclaves and host andesite in the earlier eruptive phases is no longer present, reflecting increasing hybridisation of the mafic enclaves. The majority of enclaves also have some geochemical characteristics distinctive from the earlier phase enclaves, e.g. higher MgO and lower FeO values. Successive replenishments of mafic magma have led to a more complex mixing regime as observed in the composite enclaves. The overall evolution of the geochemistry, coupled with increased textural variability across enclave types implies a correlation with the change in activity in the latter phases.

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Research paper thumbnail of Supporting Online Material for Implications of Magma Transfer Between Multiple Reservoirs on Eruption Cycling

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Research paper thumbnail of Hazard implications of small-scale edifice instability and sector collapse: a case history from Soufrière Hills Volcano, Montserrat

Geological Society, London, Memoirs, 2002

During the 1995 to 1998 phase of dome growth at Soufrière Hills Volcano on Montserrat, we documen... more During the 1995 to 1998 phase of dome growth at Soufrière Hills Volcano on Montserrat, we documented instability of the steep southern rim of English's Crater, known as Galway's Wall. The horseshoe-shaped English's Crater provided good evidence for previous sector collapses, and assessments undertaken in late 1996 anticipated the possibility of a partial sector collapse and a SW-directed explosion, hazards previously unrecognized on Montserrat.A change from predominantly endogenous to exogenous growth of the lava dome at the end of 1996 eased the stress on the southern sector. However, rapid dome growth in November and December 1997 led to severe reloading and eventual sector failure at the base of the buried Galway's Wall and in the adjacent hot-spring area. This failure resulted in the debris avalanche and lateral blast of 26 December 1997.Similar sector collapses at a number of small volcanoes in the Caribbean, as well as worldwide, are evidence that edifice insta...

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Research paper thumbnail of Chapter 15 The SEA-CALIPSO volcano imaging experiment at Montserrat: plans, campaigns at sea and on land, scientific results, and lessons learned

Geological Society, London, Memoirs, 2014

Since 1995 the eruption of the andesitic Soufrière Hills Volcano (SHV), Montserrat, has been stud... more Since 1995 the eruption of the andesitic Soufrière Hills Volcano (SHV), Montserrat, has been studied in substantial detail. As an important contribution to this effort, the Seismic Experiment with Airgunsource-Caribbean Andesitic Lava Island Precision Seismo-geodetic Observatory (SEA-CALIPSO) experiment was devised to image the arc crust underlying Montserrat, and, if possible, the magma system at SHV using tomography and reflection seismology. Field operations were carried out in October–December 2007, with deployment of 238 seismometers on land supplementing seven volcano observatory stations, and with an array of 10 ocean-bottom seismometers deployed offshore. The RRS James Cook on NERC cruise JC19 towed a tuned airgun array plus a digital 48-channel streamer on encircling and radial tracks for 77 h about Montserrat during December 2007, firing 4414 airgun shots and yielding about 47 Gb of data. The main objecctives of the experiment were achieved. Preliminary analyses of these d...

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Research paper thumbnail of The 1995–1998 eruption of the Soufriére Hills volcano, Montserrat, WI

Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2000

Eruption of the Soufriere Hills volcano began on 18 July 1995 after three years of elevated seism... more Eruption of the Soufriere Hills volcano began on 18 July 1995 after three years of elevated seismic activity. Four months of increasingly vigorous phreatic activity culminated in mid-November 1995 with the initiation of dome growth. Growth rates increased unevenly through early March ...

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Research paper thumbnail of Timescales of magma ascent and degassing and the role of crustal assimilation at Merapi volcano (2006–2010), Indonesia: Constraints from uranium-series and radiogenic isotopic compositions

Geochimica et Cosmochimica Acta, Feb 1, 2018

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Research paper thumbnail of SedCas_Volcano: Simulating decadal patterns of lahar hazard and sediment transfer following volcanic disturbance in the Belham River Valley, Montserrat&#160

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Chapter 16 Pre-eruptive vapour and its role in controlling eruption style and longevity at Soufrière Hills Volcano

Geological Society, London, Memoirs, 2014

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Research paper thumbnail of Transitions between explosive and effusive phases during the cataclysmic 2010 eruption of Merapi volcano, Java, Indonesia

Bulletin of Volcanology, Jul 18, 2016

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Research paper thumbnail of Catastrophic lava dome failure at Soufrière Hills Volcano, Montserrat, 12–13 July 2003

Journal of Volcanology and Geothermal Research, Dec 1, 2005

... July (Table 1) and presumably was caused by the large volume of pyroclastic flow material dis... more ... July (Table 1) and presumably was caused by the large volume of pyroclastic flow material displacing ... the shoreline was eroded by the tsunami, indicating that the surge was emplaced before the ... to have been generated during the most intense stages of the lava dome unloading ...

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Research paper thumbnail of Field measurements of the rheological and thermal properties of lavas from the East Rift Zone, Hawaii

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Little and often or once in a while with a bang? Quantifying lahar hazard on Montserrat

Bookmarks Related papers MentionsView impact

Research paper thumbnail of An application-driven approach to terrain model construction

International Journal of Geographical Information Science, Jun 21, 2010

Terrain is a surface phenomenon that is measured, modelled, and mapped. However, it is continuous... more 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

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Hazard implications of small-scale edifice instability and sector collapse: a case history from Soufrière Hills Volcano, Montserrat

Geological Society, London, Memoirs, 2002

During the 1995 to 1998 phase of dome growth at Soufrière Hills Volcano on Montserrat, we documen... more During the 1995 to 1998 phase of dome growth at Soufrière Hills Volcano on Montserrat, we documented instability of the steep southern rim of English's Crater, known as Galway's Wall. The horseshoe-shaped…

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Research paper thumbnail of Volatile and light lithophile trace element geochemistry of the 2010 and other recent eruptions of Merapi volcano, Java, Indonesia:NERC Scientific Facilities and Technology Ion Microprobe Facility – 2012 Annual Science Report

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Insights into Magmatic Degassing at Merapi Volcano, Indonesia from Uranium-Series Disequilibria in Recently Erupted Volcanic Rocks

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Rapid eruptive transitions from low to high intensity explosions and effusive activity: insights from textural analysis of a small-volume trachytic eruption, Ascension Island, South Atlantic

Bulletin of Volcanology, 2021

Proximal deposits of small-volume trachytic eruptions are an under-studied record of eruption dyn... more Proximal deposits of small-volume trachytic eruptions are an under-studied record of eruption dynamics despite being common across a range of settings. The 59 ± 4 ka Echo Canyon deposits, Ascension Island, resulted from a small-volume explosive-effusive trachytic eruption. Variations in juvenile clast texture reveal changes in ascent dynamics and transitions in eruption style. Five dominant textural types are identified within the pumice lapilli population. Early Strombolian-Vulcanian eruption phases are typified by macro- and micro-vesicular equant clast types. Sheared clasts are most abundant at the eruption peak, transitioning to dense clasts in later phases due to shear-induced coalescence, outgassing and vesicle collapse. Melt densification and outgassing via tuffisite veins increased plume density, contributing to partial column collapse and the explosive-effusive transition. Bulk vesicularity distributions indicate a shift in dominant fragmentation mechanism during the erupti...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Mafic enclaves record syn-eruptive basalt intrusion and mixing

Earth and Planetary Science Letters, 2018

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Research paper thumbnail of The Ongoing Eruption in Montserrat

Science, 1997

... the new techniques developed are making this eruption one of historic importance to ... the c... more ... the new techniques developed are making this eruption one of historic importance to ... the continuing activity, but the social and economic pressure building on officials ... Murray. , eds (1995) Monitoring Active Volcanoes: Strategies, Procedures and Techniques (University College ...

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Research paper thumbnail of Ground deformation at Soufrière Hills Volcano, Montserrat during 1998–2000 measured by radar interferometry and GPS

Journal of Volcanology and Geothermal Research, 2006

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Research paper thumbnail of Mafic enclave diversity at the Soufrière Hills Volcano, Montserrat

ABSTRACT The andesitic Soufrière Hills Volcano, Montserrat has been active since 1995, with five ... more ABSTRACT The andesitic Soufrière Hills Volcano, Montserrat has been active since 1995, with five phases of dome growth to date. Mafic enclaves are ubiquitous, and supply of mafic magma is interpreted as the main driver for the current eruption. Recent (Phases IV to V) activity has changed from longer periods of dome growth to shorter more intensive episodes. This is coincident with an increase in the abundance and heterogeneity of mafic enclaves, implying that the changes in activity may reflect differences within the magmatic system. The intense Phase V episode lasted ~18 weeks, culminating in the energetic collapse of Feb. 11th 2010. Within these deposits three distinct mafic enclave types have been identified using textural and geochemical variations: (A) Weakly porphyritic basaltic enclaves; with chilled margins and inherited phenocryst proportions of < 8%. (B) Medium to highly porphyritic basaltic-andesite enclaves; with diffuse margins and inherited phenocryst proportions of 16-25%. (C) Composite; a mixture of types A and B indicating two-stage mixing. Textural and petrological variations also includes differences in: vesicularity, modal mineral assemblages, glass abundance, groundmass size and distribution. Inherited phenocrysts show petrological and geochemical characteristics consistent with late stage heating and inheritance from the andesite. Bulk XRF analyses of Phase V enclaves shows a wide compositional range of 48-58wt% SiO2. An observed SiO2 compositional gap between the mafic enclaves and host andesite in the earlier eruptive phases is no longer present, reflecting increasing hybridisation of the mafic enclaves. The majority of enclaves also have some geochemical characteristics distinctive from the earlier phase enclaves, e.g. higher MgO and lower FeO values. Successive replenishments of mafic magma have led to a more complex mixing regime as observed in the composite enclaves. The overall evolution of the geochemistry, coupled with increased textural variability across enclave types implies a correlation with the change in activity in the latter phases.

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Research paper thumbnail of Supporting Online Material for Implications of Magma Transfer Between Multiple Reservoirs on Eruption Cycling

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Hazard implications of small-scale edifice instability and sector collapse: a case history from Soufrière Hills Volcano, Montserrat

Geological Society, London, Memoirs, 2002

During the 1995 to 1998 phase of dome growth at Soufrière Hills Volcano on Montserrat, we documen... more During the 1995 to 1998 phase of dome growth at Soufrière Hills Volcano on Montserrat, we documented instability of the steep southern rim of English's Crater, known as Galway's Wall. The horseshoe-shaped English's Crater provided good evidence for previous sector collapses, and assessments undertaken in late 1996 anticipated the possibility of a partial sector collapse and a SW-directed explosion, hazards previously unrecognized on Montserrat.A change from predominantly endogenous to exogenous growth of the lava dome at the end of 1996 eased the stress on the southern sector. However, rapid dome growth in November and December 1997 led to severe reloading and eventual sector failure at the base of the buried Galway's Wall and in the adjacent hot-spring area. This failure resulted in the debris avalanche and lateral blast of 26 December 1997.Similar sector collapses at a number of small volcanoes in the Caribbean, as well as worldwide, are evidence that edifice insta...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Chapter 15 The SEA-CALIPSO volcano imaging experiment at Montserrat: plans, campaigns at sea and on land, scientific results, and lessons learned

Geological Society, London, Memoirs, 2014

Since 1995 the eruption of the andesitic Soufrière Hills Volcano (SHV), Montserrat, has been stud... more Since 1995 the eruption of the andesitic Soufrière Hills Volcano (SHV), Montserrat, has been studied in substantial detail. As an important contribution to this effort, the Seismic Experiment with Airgunsource-Caribbean Andesitic Lava Island Precision Seismo-geodetic Observatory (SEA-CALIPSO) experiment was devised to image the arc crust underlying Montserrat, and, if possible, the magma system at SHV using tomography and reflection seismology. Field operations were carried out in October–December 2007, with deployment of 238 seismometers on land supplementing seven volcano observatory stations, and with an array of 10 ocean-bottom seismometers deployed offshore. The RRS James Cook on NERC cruise JC19 towed a tuned airgun array plus a digital 48-channel streamer on encircling and radial tracks for 77 h about Montserrat during December 2007, firing 4414 airgun shots and yielding about 47 Gb of data. The main objecctives of the experiment were achieved. Preliminary analyses of these d...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The 1995–1998 eruption of the Soufriére Hills volcano, Montserrat, WI

Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2000

Eruption of the Soufriere Hills volcano began on 18 July 1995 after three years of elevated seism... more Eruption of the Soufriere Hills volcano began on 18 July 1995 after three years of elevated seismic activity. Four months of increasingly vigorous phreatic activity culminated in mid-November 1995 with the initiation of dome growth. Growth rates increased unevenly through early March ...

Bookmarks Related papers MentionsView impact