Reading 3 Flashcards
Describe what occurs in the lead up to a mega - thrust earthquake
firstly, the tectonic plates move toward one another continually, but can get stuck when in contact, creating over long periods of time an immense build up of strain that eventually exceeds the friction between them. At this point, the earthquake occurs.
How does a core sample from the ocean floor reveal a past earthquake event?
- a multi sensor core logger machine is used to examine a core sample brought up from the ocean floor. the analogous band of rock and chunks of wood debris that interrupt the core’s muted brown tells a story. in the context of the text, the earthquake triggered a landslide, the debris fingerprint of which had been captured in the core sample and was analyzed
Why was the Christchurch earthquake of 2011 a surprise to scientists?
the challenge in studying earthquakes is that like the tectonic plates it studies, earthquakes science never keeps still. With specific regard to the 2011 Christchurch earthquake, scientists did not even know there was a fault in the region until a much less damaging magnitude 7.1 earthquake occurred in September 2010.
What is the proposed reason for the seismic activity on baffin island in nunavut?
Observations on how the surface of the island is currently bulging up two millimeters per year on its western edge informs models of where the north american plate and Juan DE fuca plate are locked and storing the greatest amount of energy
What is currently occurring on Vancouver Island that provides a clue to a potential future earthquake there?
Gps technolgoy stations on the island, scientists can now know the eastern edge of the potential rupture zone for a megathrust earthquake.
What are the beneficial applications of the motion sensors that oceans network Canada is currently prototyping in Vancouver?
These motion sensors will allow for a rapid detection and reporting of spreading seismic waves before they reach vancouver or victoria. Allowing airports to stop planes from being active, gas companies will be able to turn off supply and bridge entrance lights could turn red. Overall, they would help mitigate the secondary impacts of the earthquake.
How have indigenous people on the west coast of the island been preparing for a potential tsunami?
The indigenous people have built their “big house up on the hill across the river and are in the process of building a subdivision there also”. Furthermore, the daycare centre often runs drills to prepare them for hazards
Based on the window forecasted by the scientists at the Sidney laboratory, in what time range will the next strong earthquake occur in the region? (Provide the range by giving the specific years).
Last earthquake was 315 years ago, a number that is five years away from being within Randy Enkin’s window of megathrust earthquake recurrence. According to the GPS units on the island the next earthquake could hit at any moment but it is impossible to say as of right now.
