On December 26 2004, a huge magnitude 9.2 Mw earthquake struck off the coast of Indonesia beneath the Indian Ocean. This undesea meagthrust earthquake became later known as the Sumatra-Andaman earthqauke. The earthquake generated a tsunami with waves reaching up to 30m (100ft) in height. At the time warning buoys were not in opeation in this part of the world and while the earthquake was devastating, the tsunami wave that followed was largely unwarned, especially for those living in nearby Banda Aceh, Indonesia. In all the combination of deaths fro the earthquake, tsunami and later disease, claimed the lives of more than 230,000 people.
At the time I was working as a Geography teacher in Ilford, Essex, UK. I noticed that students (I taught 11-18 year old students), were asking questions and wanted to try and understand what had occurred. I had raised money for and purchased a sesimograph from the United States in 2004 and had installed this prior to the earthquake. In fact, I had just returned from the American Geophysical Union (AGU) meeting in San Francisco where I presented a poster on teaching sesismology to high school students in the UK.
The photograph, (left) shows the set up whewn I had later fitted a dampening mechanism to the setup. When the earthquake occured it was a teleseismic event and easily measured, even by my relatively old-fashioned sesimograph. This allowed me to present the data and show the animation of the p-waves ans s-waves as the earthquake sent the waves of energy around the world.
I presented a series of school assemblies, using animations and props to explain how strain energy builds up and is released along a fault and how a large tsunami wave was propgated. We later produced a series of short films that along with teaching resources were included on a CD-Rom and sent to local primary shools in the area.
I also wanted to show students how earthquakes happen and ahow shake yables could be made using a variable speed drill and an offset cam to make the table move. Then, different structures with and without aseismic design could be added and tested. I even had large iron blocks to act as buildings as I lay them on wet sansd so they could see and test what happend to teh 'structures' on unconsolidated foundations (sandy, wet soil)
This was useful because it also allowed for discussion of what happened to the 911 center in the Bay area at the time of the 1989 Loma Prieta earthquake - The call center was abandoned several times beacuse shaking was magnified by the land that was built on infill from the 1906 earthquake! This is important to know because learning should not only be something that takes place in schools! Below, I am attaching some images of the shake table as well as a link to the plans (shake_table.gif) of how YOU can build one too! Look out for more content based on teaching earthquakes and sesimology soon!
