GIS in the Classroom Blog 6: How can we use GIS to investigate tectonic processes and hazards?

Geospatial resources are making an increasingly significant contribution to our knowledge and understanding of the Earth’s fundamental structure. Consequently, we need to share such developments with our students. We’ll take a glimpse into some of the ways you can do this, particularly visualisations that help us to teach about tectonic hazards. This blog includes tips on how to help students visualise the global distribution of hazards and their relationship to plate margins and movements.

ArcGIS Online has many GIS layers for tectonic processes and hazards and judicial use of these layers can really help to manage students’ cognitive load. In the Tectonic plate motion map, open access layers are combined with a time-enabled layer to show the velocity and direction (using bearings data) of tectonic plate movements in 5 million year steps. Plate names, boundary types and further details are also shown, via clickable pop-ups.[1] The excellent ‘Oceans’ base map helps to address a common misconception, reminding students that the Earth’s crust does continue beyond the edge of continents!

GIS maps are becoming available with much more fine-grained data about plate movements such as the GPS Velocity Viewer from Earthscope Consortium.

A web map such as World volcanoes and tectonic plates ELEVATION can be created quickly by adding open access GIS layers in ArcGIS Online and configuring the pop-up details according to need. Just three layers were used with this Imagery Hybrid basemap (imagery with labels). It is also straightforward to use one of the ArcGIS Online apps to add powerful extra functionality by showing elevation of the whole of the Earth’s crust including the ocean floors. An especially useful application is the creation of elevation profiles at different plate margins. In this case, we see where the oceanic Nazca Plate is subducting beneath the continental South American Plate. A simple screenshot of the elevation profile can be pasted into a presentation where value can be added with annotations. If possible, it’s better to use a video clip of the elevation profile in action. It’s better still to convert the clip to a GeoGIF which when pasted continues to play without needing to press a play button, reducing the split attention effect and reinforcing the learning. It can become ‘the GIF that keeps on giving’! A teacher can do this for expositions or set up as a task for students, scaffolded accordingly.

Use of the ArcGIS Online analysis tools can show how tectonic hazards are managed. The ‘Create Buffers’ tool was used (above) to show the Exclusion zone - Eruption site on La Cumbre Vieja September 2021.

Alistair Hamill has produced many excellent GIS resources for the study of tectonic processes and hazards, including a very accessible workflow for the Tohoku 2011 earthquake and tsunami in Japan.

Alistair has also made extensive use of seismic tomography[2] to provide students with unprecedented visualisations of tectonic processes using Hades Underworld Explorer by Atlas of the Underworld. This example shows how he has ‘added value’ to one of the scans, to step the explanation about what the tomographic scan shows.

The fascinating tectonic, long-term impact of magma plumes (mantle plumes) can be ably illustrated using GIS. A web map of the Hawaii hotspot track - Emperor and Hawaiian chains shows the changing relative location of the Hawaii Hotspot across the Pacific Plate over 85 million years. Of course, it’s important to remember that it’s the plate that’s moving, rather than the more or less static magma plume beneath the crust!

[1] Tectonic plate motion (Web App) Bearings and time data: Alistair Hamill; Mapping: Brendan Conway

[1] Seismic tomography is a technique for imaging the subsurface of the Earth with seismic waves produced by earthquakes or explosions (Wikipedia – Seismic tomography)