What is the Relationship between Lava Flow Length and Effusion Rate at Mt Etna?
This material is replicated on a number of sites as part of the SERC Pedagogic Service Project
In this Spreadsheets Across the Curriculum activity, students use data from active lava flows to search for a relationship between effusion rate and lava flow length. Students will view a video of an eruption of Mount Etna volcano and make estimations of the rate of effusion. Using linear regression, the student will create a physical model to calculate the maximum potential lava flow length. This is a self-paced activity in which students follow a PowerPoint presentation to create spreadsheets and graphs using Excel.
- Gather data on lava flow length and effusion rate.
- Find a best-fit linear model.
- Calculate a maximum potential lava flow length, based on a physical model of lava flows.
- Compare the statistical and physical model results.
- Develop a spreadsheet to carry out a calculation.
- Discover the log-log linear relationship between effusion rate and lava flow length.
- Use video footage to make estimations regarding effusion rate.
- Compare calculations from a physical model to observed data.
Context for Use
Equipment: Each student or pair of students needs a computer with Excel and PowerPoint.
Classes: This module has been used in an Introductory Physical Volcanology course with upper level undergraduates.
In the class, the module was introduced during lab to be completed as homework due the following week. Students turned in hard-copies of the Excel spreadsheets and graphs, as well as their working Excel files. This worked well for junior and senior level students with excellent quantitative skills.
Description and Teaching Materials
If the embedded spreadsheets are not visible, save the PowerPoint file to disk and open it from there. The movie file is provided separately and is required for the End of Module assignment.
This PowerPoint file is the student version of the module. An instructor version is available by request. The instructor version includes the completed spreadsheet. Send your request to Len Vacher (firstname.lastname@example.org) by filling out and submitting the Instructor Module Request Form.
Teaching Notes and Tips
This module, like the others in this collection, works best if coordinated with lecture and lab material.
If students have difficulty in getting their equations to produce the correct numbers in the orange cells -- especially if their results are off by orders of magnitude -- tell them to check their unit conversions. You cannot ever emphasize unit conversions enough.
Some students jump ahead to the end-of-module assignments without working through the main part of the module carefully. Those students have trouble.
The end-of-module questions can be used for assessment.
The instructor version contains a pre-test
References and Resources
GIffiths, R.W., 2000, The dynamics of lava flows, Annual Review of Fluid Mechanics 32: 477-518.
Kilburn, C.R.J., 2000, Lava flows and flow fields. In: Sigurdsson, H. (Editor-in-Chief). Encyclopedia of Volcanoes, Academic Press, San Diego, 291-305.
Kilburn, C.R.J., and G. Luongo (eds.), 1993, Active lava flows: monitoring and modelling, UCL Press, London.
Sakimoto, S.E.H., and T. Gregg, 2001, Channelized flow: Analytical solutions, laboratory experiments, and applications to lava flows, Journal of Geophysical Research 106: 8629-8648.