Developing an App-Based Guide into Mt. Yana, an Eroded Stratovolcano in the Southern Cascades

Abstract:

There are many opportunities for non-geologists to learn about active volcanoes, but there are few publicly accessible resources that provide an experience for how an older volcano erodes, and eventually becomes less recognizable as a volcanic edifice. For example, Mt. Yana is an approximately 3 Ma stratovolcano of the ancestral Cascades, situated approximately 20 km from the boundary with the Sierra Nevada. The field area is less than a two hours’ drive from Chico, California, and within sight of (<40 km south) Lassen Volcanic National Park, which includes ancient Mt. Tehama, an eroded stratovolcano that is still recognizable by its remnant peaks. Mt. Yana has eroded to such an extent that it is difficult to recognize as a volcanic edifice, but the degree of erosion provides easy access to the internal structures of the volcano’s eroded core. To take advantage of this, we have developed an interactive app to guide visitors with an interest in exploring the interior of a volcano on a geologic tour of Mt. Yana. The app includes a day hike with 12 stops that provide hikers with good examples of volcanic feeder dikes, lava flows, columnar jointing, debris flows, and hyaloclastite that formed when molten lava was quenched by water/ice interaction. At each stop, hikers are able to use their phone to see first-hand examples of these features, accompanied by informative explanations and engaging questions to supplement real features in front of them. The app will help users learn that volcanoes have a “lifespan,” in that younger, more familiar, and visually striking volcanoes, such as Mt. Shasta, erode into structures like Mt. Tehama, and eventually become less recognizable, like Mt. Yana. In the age of limited group sizes and physical distancing, the app may be useful as a tool for virtual field trips. In Fall 2020, a group of Junior-level geology students will use the Yana app from their homes. We will measure their learning with a pre/post-virtual field trip survey to determine the effectiveness of the app as a replacement for what they would learn on an in-person field trip.