RIPPED FROM THE HEADLINES: "JELLOEA" AND UNDERSTANDING HAWAIIAN-STYLE VOLCANIC HAZARD AND RISK

"Jelloea" is an excellent model of basaltic volcanism, especially for the current East Rift Zone eruption of Kilauea during which magma has been migrating away from the volcano’s summit before erupting out of fissures and flowing to the sea, destroying much human settlement along the way. In this activity, "volcanoes" are formed from pans of gelatin inverted onto pegboard. “Monitoring stations" (pushpins representing GPS receivers, seismometers and gas detectors) are installed. Students are asked to hypothesize about what would happen when "magma" (colored water or syrup) is injected through the pegboard into the bottom of the volcano, and also about what the monitoring stations might register as magma enters the system. STOP HERE and form your own hypotheses; the presentation will show video of the experiment. Students then proceed with injections, stopping periodically to analyze and compare their hypotheses to what actually occurs. Perhaps because they are most familiar with volcanoes that erupt from summits, students almost never predict what does happen: the transparent gelatin enables observation of the formation of dikes that propagate laterally until intersecting the flanks of the volcano, generating "lava flows" at significant distances from the summit. Students also build "settlements" in what they perceive are low risk locations based on results of initial injections. Multiple injections reflect the long-lived eruptive history of volcanoes like Kilauea and Mauna Loa and although new injections tend to feed established dike paths, the settlements are almost always eventually affected. A final and valuable step is to consider limitations of the model. As a result of this activity, the geologic map of Hawaii takes on new meaning and students better understand the mechanics of dikes and lava flows; the generation of ground deformation, seismicity and gas emission; and volcanic hazard and risk to human settlements. The current situation at Kilauea adds an important, compelling element. The activity was inspired by http://www.spacegrant.hawaii.edu/class_acts/GelVol.html