Something creepy is happening
In this activity, students explore tectonic movements called slow slips. They plot and interpret a graph using data from an actual event in New Zealand.
Slow slip event – an animation
Slow slips are silent earthquakes that occur below the Earth’s surface over a large area, unlike traditional earthquakes we feel that occur in a relatively small region.
Before discovering slow slip events, earthquakes were thought to be the only way the Earth’s crust could relieve the pent-up stresses caused by the moving tectonic plates.
Scientists are now actively working to understand the relationship between slow slips and earthquakes. There is evidence of earthquake swarms accompanying some slow slip events, suggesting a slow slip may increase stress in surrounding areas and could push an already stressed fault closer to rupture. However, in other cases, slow slip events can relieve stress on a fault, and this might postpone an earthquake.
Understanding the relationship between slow slip events and earthquakes and the collation of slow slip data will enable better earthquake forecast modelling.
This animation is a visualisation of a slow slip event.
By the end of this activity, students should be able to:
understand the difference between earthquakes and slow slips
plot and interpret data on a line graph
explain a scientific application of GPS technology.
Download the Word file (see link below) for:
introduction/background notes
what you need
what to do
discussion questions
student handout.
Activity ideas
Satellites and receiving stations play a key role in providing data about slow slips. Learn more about Earth movements, then build a satellite to monitor them and use this activity to interpret the data you receive.
Useful links
In 2011, scientists from around the world met in Gisborne to consider how to study slow slips.
Find out about slow slips recorded in Poverty Bay in 2010.