Peer-Reviewed Journal Publications

For a full and up-to-date publication list, see Google Scholar and ResearchGate.

Wallace, P.A., De Angelis, S.H., Larsen, J., Caricchi, L., Kendrick, J.E., Lavallée, Y. (2025). CO2 flushing and redox as drivers of pre-eruptive amphibole breakdown. Earth & Planetary Science Letters 667, 119532. https://doi.org/10.1016/j.epsl.2025.119532

Wallace, P.A., Otieno, V., Godec, P., Njoroge, R.W., Tubula, M.S., Cappelli, L., Kamau, P.M., Nomade, S., Mariita, N.O., Fontijn, K. (2025). Temporal and spatial evolution of explosive silicic peralkaline eruptions at the Olkaria Volcanic Complex and Longonot volcano in the Southern Kenya Rift. Journal of Volcanology and Geothermal Research 460, 108275. https://doi.org/10.1016/j.jvolgeores.2025.108275

Cappelli, L. Wallace, P.A., Mbede, E. et al. (2025). Pre-Eruptive Reservoir Conditions of the Peralkaline Rungwe Pumice Plinian Eruption (Tanzania) From Haüyne-Hosted Melt Inclusions. Journal of Petrology. https://doi.org/10.1093/petrology/egaf079

Tadesse, A.Z., Fontijn, K., Wallace, P.A. et al. (2024). Eruption style and dynamics of the ~ 87 ka Baricha peralkaline rhyolite eruption in Ethiopia. Bullein of Volcanology 86, 93. https://doi.org/10.1007/s00445-024-01787-9

Cappelli, L, Wallace, P.A., Randazzo, A. et al. (2023) Diffuse soil CO2 emissions at rift volcanoes: Structural controls and total budget of the Olkaria Volcanic Complex (Kenya) case study. Journal of Volcanology and Geothermal Research. https://doi.org/10.1016/j.jvolgeores.2023.107929

Lavallée, Y., Miwa, T., Ashworth, J.D., Wallace, P.A., Kendrick, J.E., Coats, R., Lamur, A., Hornby, A., Hess, K.-U., Matsushima, T., Nakada, S., Shimizu, H., Ruthensteiner, B., and Tuffen, H. (2021). Transient conduit permeability controlled by a shift between compactant shear and dilatant rupture at Unzen volcano (Japan). Solid Earth Discuss. [preprint], https://doi.org/10.5194/se-2021-127, in review, 2021.

Yilmaz, T., Wadsworth, F.B., Gilg, H.A., Hess, K-U., Kendrick, J.E., Wallace, P.A., Lavallée, Y., Utley, J.E.P., Vasseur, J., Nakada, S., Dingwell, D.B. (2021). Rapid alteration of fractured volcanic conduits beneath Mt Unzen. Bulletin of Volcanology, 83, 34. https://doi.org/10.1007/s00445-021-01450-7

Wallace, P.A., Lamb, O., De Angelis, S., Kendrick, J.E., Hornby, A., Díaz-Moreno, A., Gonzalez, P.J., von Aulock, F.W., Lamur, A., Utley, J.E.P., Chigna, G., Rietbrock, A., Lavallée, Y. (2020). Integrated constraints on explosive eruption intensification at Santiaguito dome complex, Guatemala. Earth and Planetary Science Letters, 536, 116139. https://doi.org/10.1016/j.epsl.2020.116139

Hughes, A., Kendrick, J.E., Lamur, A., Wadsworth, F.B., Wallace, P.A., Di Toro, G., Lavallée, Y. (2020). Frictional behaviour, wear and comminution of synthetic porous geomaterials. Frontiers in Earth Science. https://doi.org/10.3389/feart.2020.562548

Hughes, A., Kendrick, J.E., Salas, G., Wallace, P.A., Legros, F., Di Toro, G. Lavallée, Y. (2020). Shear localisation, strain partitioning and frictional melting in a debris avalanche generated by volcanic flank-collapse. Journal of Structural Geology, 104132. https://doi.org/10.1016/j.jsg.2020.104132

Eggertsson, G., Kendrick, J.E., Weaver, J., Wallace, P.A., Utley, J.E.P., Bedford, J., Allen, M., Markússon, S., Worden, R., Faulkner, D.R., Lavallée, Y. (2020). Compaction of hyaloclastite from the active geothermal system at Krafla volcano, Iceland. Structural Controls on Basin- and Crustal-Scale Fluid Flow and Resulting Mineral Reactions, special issue of Geofluids. https://doi.org/10.1155/2020/3878503

Weaver, J., Eggertsson, G., Utley, J.E.P., Wallace, P.A., Lamur, A., Kendrick, J.E., Tuffen, H., Markússon, S., Lavallée, Y. (2020). Thermal liability of hyaloclastite in the Krafla geothermal reservoir, Iceland: the impact of phyllosilicates on permeability and rock strength. Structural Controls on Basin- and Crustal-Scale Fluid Flow and Resulting Mineral Reactions, special issue of Geofluids. https://doi.org/10.1155/2020/9057193

Carter, W., Rietbrock, A., Lavallée, Y., Gottschämmer, E., Díaz Moreno, A., Kendrick, J.E., Lamb, O.D., Wallace, P.A., Chigna, G., De Angelis, S. (2020). Statistical evidence of transitioning open-vent activity towards a paroxysmal period at Volcán Santiaguito (Guatemala) during 2014–2018. Journal of Volcanology and Geothermal Research. https://doi.org/10.1016/j.jvolgeores.2020.106891 

Wallace, P.A., Kendrick, J.E., Ashworth, J.D., Miwa, T., Coats, R., De Angelis, S.H., Mariani, E., Utley, J., Biggin, A., Kendrick, R., Nakada, S., Matsushima, T., Lavallée, Y. (2019). Petrological architecture of a magmatic shear zone: A multidisciplinary investigation of strain localisation during magma ascent at Unzen Volcano, Japan. Journal of Petrology, 60(4), 791–826. https://doi.org/10.1093/petrology/egz016 

Wallace, P.A., De Angelis, S.H., Hornby, A., Kendrick, J.E., Clesham, S., von Aulock, F.W., Hughes, A., Utley, J., Hirose, T., Dingwell, D.B., Lavallée, Y. (2019). Frictional melt homogenisation during fault slip: Geochemical, textural and rheological fingerprints. Geochimica et Cosmochimica Acta, 255, 265–288. https://doi.org/10.1016/j.gca.2019.04.010 

Mordensky, S., Kennedy, B., Villeneuve, M., Lavallée, Y., Reichow, M., Wallace, P.A., Siratovich, P., Gravley, D. (2019). Increasing the permeability of hydrothermally altered andesite by transitory heating. Geochemistry, Geophysics, Geosystems. https://doi.org/10.1029/2019GC008409 

Lamb, O.D., Lamur, A., Díaz-Moreno, A., De Angelis, A., Hornby, A., von Aulock, F.W., Kendrick, J.E., Wallace, P.A., Rietbrock, A., Alvarez, A., Chigna, G., Lavallée, Y. (2019). Disruption of long-term effusive-explosive activity at Santiaguito, Guatemala. Frontiers in Earth Science. https://doi.org/10.3389/feart.2018.00253 

Harnett, C.E., Kendrick, J.E., Lamur, A., Thomas, M., Stinton, A., Wallace, P.A., Utley, J., Murphy, W., Neuberg, J., Lavallée, Y. (2019). Evolution of mechanical properties of lava dome rocks across the 1995-2010 eruption of Soufrière Hills volcano, Montserrat. Frontiers in Earth Science. https://doi.org/10.3389/feart.2019.00007 

Coats, R., Kendrick, J.E., Wallace, P.A., Miwa, T., Hornby, A., Matsushima, T., Lavallée, Y. (2018). Failure criteria for porous dome rocks and lavas: a study of Mt. Unzen, Japan. Solid Earth, 9, 1299–1328. https://doi.org/10.5194/se-9-1299-2018 

Esse, B., Burton, M., Varnam, M., Kazahaya, R., Wallace, P.A., von Aulock, F.W., Lavallée, Y., Salerno, Y., Scollo, Y., Coe, H. (2018). Quantification of ash sedimentation dynamics through depolarisation imaging with AshCam drill core. Nature Scientific Reports, 8, 15680. https://doi.org/10.1038/s41598-018-34110-6 

Doctoral Thesis (2019)

Wallace, P.A. (2019). Dynamic petrology and rheology of ascending magma during lava dome eruptions: Effusive–explosive activity. PhD Thesis, School of Environmental Sciences, University of Liverpool, Liverpool, UK. https://doi.org/10.17638/03046850

Master’s Thesis (2015)

Wallace, P.A. (2015). Vulcanian explosions at the type locality at Vulcano, Sicily. MGeol Thesis, School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK.

​Conference Proceedings

2021

Wallace, P.A., Otieno, V., Fontijn, K., Njoroge, R.W., Tubula, M.S., Cappelli, L., Mariita, N.O. Characterising the explosive history of Kenya’s geothermal powerhouse in the East African Rift: The Greater Olkaria Volcanic Complex, Abstract, AGU Fall Meeting, New Orleans, 2021.

Wallace, P.A., Fontijn, K., Otieno, V., Cappelli, L., Mariita, N. VolKenya: Rates and Styles of Volcanism Along the Central Kenya Rift, Abstract, VMSG, Online, 2021.

2020

Hartung, E., Wallace, P.A., von Aulock, F.W., Hornby, A., and Lavallée, Y. Shifting eruption dynamics: Constraints from mineral chemistry and plagioclase-hosted melt inclusions at Santiaguito volcanic dome complex, Guatemala, Abstract, EGU General Assembly, Vienna, 2020.

Harnett, C.E., Kendrick, J.E., Lamur, A., Thomas, M., Stinton, A., Wallace, P.A., Lavallée, Y. Evolution of mechanical properties of lava dome rocks across the Soufrière Hills eruption, and application in discrete element models, Abstract, EGU General Assembly, Vienna, 2020.

Wallace, P.A., Kendrick, J.E., and Lavallée, Y. Magma shearing during lava dome eruptions: from flow to failure, Abstract, VMSG, Plymouth, 2020.

2019

De Angelis, S., Rietbrock, A., Lavallée, Y, Carter, W., Wallace, P.A., and Gottschammer, A.R. An international partnership to develop volcano monitoring capacities in Guatemala, Abstract, Society of Exploration Geophysicists, San Antonio, Houston, Texas, 2019.

Hartung, E., Wallace, P.A., von Aulock, F.W., Hornby, A., and Lavallée, Y. Shallow magmatic processes at Santiaguito Dome Complex, Guatemala: New insights from plagioclase major and trace elements, Abstract, AGU Fall Meeting, San Francisco, 2019.

Wallace, P.A., De Angelis, S., Lamb, O., Kendrick, J.E., Hornby, A., von Aulock, F.W., Lamur, A., Chigna, G., Rietbrock, A., and Lavallée, Y. Disruption in eruptive longevity at a centennial volcano: Effusive-explosive activity at Santiaguito dome complex. International Union of Geodesy and Geophysics, Montreal, Canada, 2019.

Kendrick, J.E., Schaefer, L., Lamur, A., Schauroth, J., Hughes, A., Wallace, P.A., Coats, R., Kennedy, B. and Lavallée, Y. Heterogeneous systems: Laboratory constraints of volcanic rock properties, Abstract, VMSG, St. Andrews, 2019.

Kendrick, J.E., Schaefer, L., Lamur, A., Schauroth, J., Hughes, A., Wallace, P.A., Coats, R., Kennedy, B. and Lavallée, Y. Using novel, integrated approaches to measure volcanic rock properties, Abstract, AGU Fall Meeting, Washington, 2019.

2018

Wallace, P.A., De Angelis, S., Lamb, O., Kendrick, J.E., Hornby, A., von Aulock, F.W., Lamur, A., Chigna, G., Rietbrock, A., Dingwell, D.B., and Lavallée, Y. Temporal dynamics in Vulcanian explosivity as recorded by petrological, geochemical and geophysical observations at Santiaguito volcano, Guatemala, Abstract, Cities on Volcanoes, Napoli, Italy, 2018.

Coats, R., Kendrick, J.E., Wallace, P.A., Hornby, A., Miwa, T., Ashworth, J.D., and Lavallée, Y. The samples flowed before the experimentalist: A failure criterion for porous, volcanic material, Abstract, EGU General Assembly, Vienna, 2018.

Wallace, P.A., De Angelis, S.H., Kendrick, J.E., Hornby, A., von Aulock, F.W., Clesham, S., Hirose, T., Dingwell, D.B., and Lavallée, Y. Geochemical response to frictional melting in a volcanic conduit: Implications for eruption dynamics, Abstract, TSG-MSG, Plymouth, 2018.

2017

Wallace, P.A., Kendrick, J.E., De Angelis, S.H., Ashworth, J.D., Coats, R., Miwa, T, Mariani, E., and Lavallée, Y. Shearing and friction in the volcanic conduit: A crystal constraint, Abstract, AGU Fall Meeting, New Orleans, 2017.

Kendrick, J.E., Wallace, P.A., Coats, R., Lamur, A., Lavallée, Y. Examining shear processes during magma ascent, Abstract, AGU Fall Meeting, New Orleans, 2017.

Coats, R., Cai, B., Kendrick, J.E., Wallace, P.A., Dobson, K., Hornby, A., Miwa, T., Ashworth, J.D., von Aulock, F.W., Godinho, J., Atwood, R.C., Lee, P.D., and Lavallée, Y. Understanding the rheology of two and three-phase magmas, Abstract, AGU Fall Meeting, New Orleans, 2017.

Wallace, P.A., Kendrick, J.E., De Angelis, S.H., Ashworth, J.D., Coats, R., Miwa, T, Mariani, E., and Lavallée, Y. Late-stage magmatic heating and deformation during the 1994 spine extrusion at Unzen volcano, Japan, Abstract, IAVCEI, Portland, Oregon, 2017.

De Angelis, S.H., Wallace, P.A., Kendrick, J.E., Hornby, A., von Aulock, F.W., Clesham, S., Hirose, T., Dingwell, D.B., and Lavallée, Y. Impact of mineralogy on frictional melting in the conduit: An experimental study of Soufrière Hills Volcano and Volcán de Colima, Abstract, IAVCEI, Portland, Oregon, 2017.

Lamb, O., Wallace, P.A., De Angelis, S., Lavallée, Y., Lamur, A., Hornby, A., von Aulock, F.W., Kendrick, J.E., Chigna, G., Pineda, A., Diaz-Moreno, A., and Rietbrock, A. Geophysical and geochemical observations of explosion dynamics at Santiaguito, Guatemala, Abstract, IAVCEI, Portland, Oregon, 2017.

Kendrick, J.E., Lavallée, Y., Wallace, P.A., Coats, R., Ashworth, J.D., Hornby, A., Lamur, A., Hughes, A., Lamb, O., von Aulock, F.W., De Angelis, S.H., and De Angelis, S. Shear zone development during the ascent of highly viscous magma, Abstract, IAVCEI, Portland, Oregon, 2017.

Cai, B., Coats, R., Lavallée, Y., Le Gall, N., Wallace, P.A., Atwood, R., Lee, P., Kendrick, J.E., and von Aulock, F.W. 4D Synchrotron Imaging of Viscous Flow of Crystal-bearing Magma Melts, Abstract, IAVCEI, Portland, Oregon, 2017.

Ashworth, J.D., Kendrick, J.E., Lamur, A., von Aulock, F.W., Wallace, P.A., Coats, R., Varley, N., and Lavallée, Y. The effect of strain on the formation and connectivity of bubbly magmas, Abstract, IAVCEI, Portland, Oregon, 2017.

Coats, R., Cai, B., Kendrick, J.E., Wallace, P.A., Hornby, A., Miwa, T., Ashworth, J.D., von Aulock, F.W., Godinho, J., Atwood, R.C., Lee, P.D., and Lavallée, Y.  An experimental investigation into magma rheology using natural and analogue materials, Abstract, IAVCEI, Portland, Oregon, 2017.

Gilg., H.A., Yilmaz, T., Wallace, P.A., Kendrick, J.E., Utley, J., Lavallée, Y., Hess, K.U., Nakada, S., and Dingwell, D.B. Hydrothermal alteration of feeder dykes of the 1990–1995 eruption at Mt Unzen, Japan, Abstract, Clay Minerals Society Annual Meeting, Edmonton, Alberta, Canada, 2017.

Wallace, P.A. Thermal destabilisation of magma in the shallow volcanic conduit, Abstract, Postgraduate Research Conference, University of Liverpool, 2017.

Wallace, P.A., Kendrick, J.E., De Angelis, S.H., Ashworth, J.D., Coats, R., Miwa, T, Mariani, E., and Lavallée, Y. The influence of strain localisation on spine extrusion dynamics during the 1991-1995 eruption at Unzen volcano, Japan, Abstract, EGU General Assembly, Vienna, 2017.

Wallace, P.A., De Angelis, S.H., De Angelis, S., Kendrick, J.E., Hornby, A., Lamb, O., von Aulock, F.W., Lamur, A., Chigna, G., Rietbrock, A., Dingwell, D.B., and Lavallée, Y. Petrological and geochemical constraints on the recent increase in explosive activity at Santiaguito volcano, Guatemala, Abstract, EGU General Assembly, Vienna, 2017.

Ashworth, J.D., Lavallée, Y., Wallace, P.A., Kendrick, J.E., Coats, R., and Miwa, T. Permeability evolution governed by shear: An example during spine extrusion at Unzen volcano, Japan, Abstract, EGU General Assembly, Vienna, 2017.

Lavallée, Y., Cai, B., Coats, R., Kendrick, J.E., von Aulock, F.W., Wallace, P.A., Le Gall, N., Godinho, J., Dobson, K., Atwood, R.C., Holness, M., and Lee, P.D. Illuminating magma shearing processes via synchrotron imaging, Abstract, EGU General Assembly, Vienna, 2017.

Wallace, P.A., De Angelis, S.H., Kendrick, J.E., Hornby, A., von Aulock, F.W., Clesham, S., Hirose, T., Dingwell, D.B., and Lavallée, Y. Chemical hysteresis during frictional melting: Rheological implications for slip dynamics in volcanic systems, Abstract, Joint Assembly (VMSG-TSG-BGA), Liverpool, 2017.

Ashworth, J.D., Lavallée, Y., Wallace, P.A., Kendrick, J.E., Coats, R., and Miwa, T. Shear regime controls on permeability during magma extrusion at Unzen volcano, Japan, Abstract, Joint Assembly, Liverpool, 2017.

Coat, R., Kendrick, J.E., Godinho, J., Cai, B., von Aulock, F.W., Wallace, P.A., Lee, P.D., and Lavallée, Y. An investigation of the effect of crystals on magma flow and failure, Abstract, Joint Assembly (VMSG-TSG-BGA), Liverpool, 2017.

2016

Coats, R., Kendrick, J.E., Wallace, P.A., Miwa, T., Hornby, Ashworth, J.D., and Lavallée, Y. Lava dome eruptions: testing strain rate dependence of porous lava rheology, Abstract, Britsh Geophysical Association Postgraduate Research in Progress Meeting, London, 2016.

Wallace, P.A., Kendrick, J.E., Lavallée, Y., Ashworth, J.D., Mariani, E., von Aulock, F., Coats, R., and Miwa, T. The effect of crystal plasticity and mineral stability on the rheological properties of magma during spine extrusion at Unzen, Japan, Abstract, EGU General Assembly, Vienna, 2016.

Ashworth, J.D., Lavallée, Y., Wallace, P.A., Lamur, A., Kendrick, J.E., and Miwa, T. The effect of shear on permeability in a volcanic conduit: a case study at Unzen volcano, Japan, Abstract, EGU, Vienna, 2016.

Coats, R., Lavallée, Y., Kendrick, J.E., Wallace, P.A., Ashworth, J.D., Hornby, A., and Miwa, T. The effect of porosity and crystallinity on magma rheology at Unzen volcano, Japan, Abstract, EGU General Assembly, Vienna, 2016.

Wallace, P.A., Kendrick, J.E., Lavallée, Y., Ashworth, J.D., Mariani, E., Coats, R., von Aulock, F., and Miwa, T. Petrological constraints on the deformation mechanisms during spine extrusion at Unzen volcano, Japan, Abstract, VMSG, Dublin, 2016.

Ashworth, J.D., Lavallée, Y., Wallace, P.A., Lamur, A., Kendrick, J.E., Coats, R., and Miwa, T. The relationship between shear and permeability: A case study at Unzen volcano Japan, Abstract, VMSG, Dublin, 2016.

Coats, R., Lavallée, Y., Kendrick, J.E., Wallace, P.A., Ashworth, J.D., Hornby, A., and Miwa, T. What makes magma go tick, tick, boom? An investigation into magma rheology using synthetic and natural materials, Abstract, VMSG, Dublin, 2016.