I'm a broadly trained volcanologist interested in:
1) developing new ways to model and assess lava flow hazards
2) using various radar methods to study volcanic deposits
3) exploring new ways to improve how hazard and risk are understood and communicated
4) understanding the links between tectonics and volcanism
Dr Lis Gallant
University of Cambridge
Department of Geography
Downing Place, Cambridge
BA in Geology • 2012
Honors Thesis: Understanding the Eruptive History of Vulcan Santa Ana, El Salvador
BS in Electronic Media, Arts, and Communications • 2009
Research Associate• March 2020 - Present
Field Camp Coordinator• Summer 2015 - Summer 2019
Graduate Teaching Assistant• 2013-2018
Expert in volcanic hazard assessment methods• September 2018 - Present
Intern• November 2012 - July 2013
My research is focused on improving our understanding of volcanic hazards and advancing the methods we use to communicate those hazards.
A grand challenge of lava flow modeling is to incorporate changing rheology and channel dynamics into quantitative models; current lava flow models are unable to successfully accommodate lava flow breakouts or dynamic changes in eruptive parameters (e.g. changes in effusion rate). While some lava flow models are able to forecast time-independent topographically controlled branching, no computational programs are currently able to model rheologically controlled flow breakouts or overflows. I am interested in using analogue models to close this gap. Using velocity measurements as a proxy for viscosity, we can gain insight into how the rheologic properties of lava evolve over time. Doing so at a manageable scale in high spatio-temporal resolution will allow for the step-wise quantification of how channels and networks grow and evolve as a function of vent dynamics, which can then be mathematically modeled. These models are necessary to create the ”rules” upon which computational codes are built.
I am interested in using ground-based radar as a tool to monitor active lava flows. Ground based radar can create rapid sequences of digital elevation models (<5 minutes between each scan); this technology allows for the quantification of real time changes in morphology and lava flow velocity, which are important variables for lava flow models. I am also interested in using this technique to monitor deformation associated with explosive volcanism. The instrument can be used to create high-resolution DEMs in steep terrain (sub-cm scale, depending on conditions). The rapidly aquired DEMs provide a useful time series for monitoring changing ground conditions that may encourage lahar formation or rockfalls.
Improvments on how model uncertainty is communicated are needed to incorporate the increasing complexity of forecasting tools into the way we illustrate hazards. New visualization methods will be required to present the full range of scenarios. Simple web-based hazard maps have proven very successful in disseminating information during the June 2018 eruption of Fuego, Guatemala. I would like to use the results of probabilistic modeling in the development of a new interactive mapping framework. The increasingly digital landscape of the future necessitates this type of approach.
Determining where activity will occur is one of the most important elements of assessing hazards and determining the subsequent risk. Spatial density estimation for volcanic vent distribution is used as a proxy for processes occurring at depth that control magma flux in a given region. By going straight from surface to source, we ignore the important role that crustal heterogeneities and tectonic setting play in vent distribution at a local scale. By creating a more accurate picture of the subsurface through ground penetrating radar, magnetic, and gravity based measurements, appropriate adjustments that account for the role of geology can be applied to spatial density estimates to make them more accurate. By combining these methods with tools from geomorphology (TCN and OSL dating techniques), we can better understand the evolution of these landscapes through time. These efforts will reduce uncertainty for subsequent modelling that relies on vent density estimation as a critical variable (i.e., tephra dispersion and lava flow inundation).
8. Germa, A., Koebli, D., Wetmore, P., Arias, A., Savov, I., Gallant, E., Richardson, J. (in review), Petrogenesis of the San Rafael subvolcanic field, Utah: implication for the in-situcrystallization and segregation of syenite in shallow sills.
7. Gallant, E., Deng, F., Connor, C., Saballos, J.A., Guitierrez, C., Myhre, D., Zayac, J., Richardson, J. Charbonnier, S., Thompson, G., Connor, L., Malservisi, R., LaFemina, P., and Dixon, T., Deep and rapid thermo-mechanical erosion by a small-volume lava flow. EPSL [download]
6. Connor, C. B., Connor, L.J., Germa, A., Richardson, J.A., Bebbington, M., Gallant, E., and Saballos, J.A., (2019, in press) How to estimate the probable locations of future volcanic vents using kernel density estimation, Statistics in Volcanology 4. (cited by 1)
5. Deng, F.,Rodgers, M., Xie, S., Dixon, T., Charbonnier, S., Gallant, E., López-Velez, C., Ordoñez, M., Malservisi, R., Voss, N, Richardson, J., (2019), High-resolution DEM generation from multiple remote sensing data sources for improved volcano hazard assessment - a case study at Nevado del Ruiz, Colombia: Remote Sensing of Environment, vol. 233. (cited by 2) [download]
4. Xie, S., Gallant, E., Wetmore, P., Owen, L., Figueiredob, P., Malservisi, R., and Dixon, T., (2019), A new geological slip rate estimate for the Calico Fault, eastern California: Implications for geodetic versus geologic rate estimates in the Eastern California Shear Zone: International Geology Review. vol. 61:13, p. 1613-1641. (cited by 1) [download]
3. Gallant, E., Richardson, J., Connor, C., Wetmore, P., and Connor, L., (2018), A new approach to probabilistic lava flow hazard assessments, applied to the Idaho National Laboratory, eastern Snake River Plain, Idaho, USA: Geology, vol. 46:10, p. 895-898. (cited by 7) [download]
2. Richardson, J.A., Connor, C., Wetmore, P.H., Connor, L., and Gallant, E.,(2015) Role of sills in the development of volcanic fields: Insights from lidar mapping surveys of the San Rafael Swell, Utah: Geology, vol. 43:11, p. 1023-1026. (cited by 16) [download]
1. George, O., McIlrath, J., Farrell, A., Gallant, E., Tavarez, S., Marshall, A., McNiff, C., Njoroge, M., Wilson, J., Connor, C., Connor, L., and Kruse, S. (2015): High-Resolution Ground-Based Magnetic Survey of a Buried Volcano Anomaly B, Amargosa Desert, NV: Statistics in Volcanology, vol. 1, p. 1-23. (cited by 8) [download]
2. LaFemina, P., Roman, D., Connor, C., Saballos, A., Gallant, E., Wauthier, C., Dixon, T.H., Tenorio, V., Strauch, W., Thompson, G., de Moor, M., Martinez, M., Feineman, M., and Longpré, M.A., (in prep), Transition from effusive to explosive activity during the 2015-2016 eruption of Momotombo Volcano, Nicaragua.
1. Gallant, E., and Connor, C., (in prep) Modeling eruptive events using cluster analysis: An example from Craters of the Moon, Idaho.
Paleotopography Reconstruction: This code removes the topographic signals associated with channels/levees on conic surfaces. [download]
Event Modeling: This code uses cluster analysis to model events from point source data in distributed volcanic fields. [download]
GPR uses a variety of signals (50-800 MHz) to image near-surface stratigraphy. Colleagues and I have used GPR to survey the tephra blankets of cinder cones in distributed volcanic fields, colluvial wedges of faults, near-vent stratigraphy of rhyolitic domes, buried lava flow margins, and to identify ice deposits buried by tephra.
TRI is a ground-based scanning radar that measures the amplitude and phase of a backscattered microwave signal (1.74 cm λ). It can be used to measure velocities of deforming objects over short timescales (minutes between scans) and can create a time series of digital elevation models (DEMs) due to the offset of the two receiving antennae. Colleagues and I have used GPR to create high resolution DEMs and track deformation during periods of volcanic unrest.
High resolution elevation datasets are useful for studying the complexities of different landscape features, for processing other geophysical data, and for hazard modeling. Colleagues and I have integrated Structure-from-Motion (SfM) DEMs with satellite and ground-based radar DEMs to create high resolution models for volcanic hazard assessments. We have also used lidar to study dike and sill thicknesses in distributed volcanic fields, as well as the complexity of deposits from explosive volcanic eruptions.
Magnetic surveys measure the intensity of the magnetic field, which is sensitive to different magnetized deposits in the sub-surface. Colleagues and I have conducted magnetic surveys to locate buried volcanic features in sedimentary basins.
Gravity surveys measure changes in the gravitational field at the surface and used to infer the density of materials in the sub-surface. Colleagues and I have conducted microgravity surveys to detect basin structures in the American west and to map extinct rift zones in Hawai'i.
Optically stimulated luminescence (OSL) dating determines the time elapsed since a sediment sample was last exposed to daylight. Cosmic rays generate terrestrial cosmogenic nuclides (TCNs) in Earth’s atmosphere and surface that are produced at a known rate and can be used to date a variety of materials and processes. Colleagues and I have used both of these techniques to date alluvial fan surfaces to determine fault slip rates in southern California.
Integrating geologic studies with geophysical surveys is a crucial step for the application of these techniques. I have receieved extensive training in field mapping and stratigraphy in a wide range of geologic settings. I have also helped train hundreds of USF students in these techniques through my participation with our summer Field School.
Quantifying geologic hazards becomes societally relevant when we view these phenomena in their relation to populations and infrastructure. Social science surveying techniques are an important method for capturing public perception of risk and hazard. I have helped disseminate surveys associated with disaster risk perception. I have also helped colleagues create and analyze surveys on evaluating engagement in technology based approaches to accessible geoscience field learning and satisfaction with geoscience training.
I am committed to providing a quality educational experience for all students. I have established myself as an approachable door-open educator and encourage co-operative learning through mutual respect. As a member of several underserved communities within the geosciences, my experiences allow me to help others navigate similar bumps during their educational careers. Encouraging students from all backgrounds to become geoscientists will only strengthen our field and I am firmly committed to this goal. Representation matters and I have aggressively used my position with the Tampa Taste of Science Festival to boost the visibility of members from communities that have been traditionally marginalised in STEM. There is no better recruiting tool than showing future scientists that, regardless of who they are or where they come from, they are welcome.
Sedimentary Petrology • University of South Florida • Spring 2020
Introduction to Earth Science • University of South Florida • Spring 2020
History of Life • University of South Florida • Fall 2019
Structural Geology and Tectonics• University of South Florida • Spring 2019
Structural Geology and Tectonics• University of South Florida • Fall 2017, Spring 2018
Introduction to Geology• University of South Florida • Fall 2015, Spring 2016
Sedimentary Processes• University of South Florida • Fall 2015
Mineralogy and Petrology• University of South Florida • Fall 2013, Spring 2014
Dynamic Earth• University of South Florida • Spring 2017, Spring 2018
Geology For Engineers• University of South Florida • Fall 2015, Spring 2016
Introduction to Geology Laboratory • Buffalo State College • Spring 2011
Intermediate Digital Imaging• Rensselaer Polytechnic Institute • Spring 2008
Inaugural speaker for the USF Library's Calling Earth Podcast: [listen here]
Interviewed by the Nicaraguan press while responding to the 2015-2016 eruption of Momotombo Volcano: [view here]
Interviewed by USF's student newspaper about my work in Nicaragua: [view here]
Interviewed by the Tampa Bay Times about my work in conjunction with the Taste of Science: [view here]