Chapter 4 Flashcards
- Notable example of successful earthquake predictions.
Feb 1975 Haicheng, China
Because of a series of foreshocks, changes in land elevation, changes in the Earth’s magnetic field, and strange animal behaviour authorities realized that an earthquake was likely to happen and issued a warning for people to remain outside.
Shortly after, a 7.3 magnitude earthquake happened which caused considerable damage but minimal loss of life.
Other ways to predict and control earthquakes:
In terms of control, is it possible to initiate, stop or affect an earthquake once is has started?
1960 a series of earthquakes were accidentally triggered in Colorado. As a result of efforts to dispose of liquid waste underground. A series of previously unknown faults were ‘lubricated’. This reduced the friction between rock bodies which allowed them to move and cause earthquakes.
This then lead to speculation that somehow earthquakes cause be managed.
What are some of the ramifications of injecting fluids into a fault zone?
The problem is that all this has to happen deep underground.
It is not possible to reliably map a fault, predict where the fluid will go or what it will do
The earthquake you hope for may or may not happen.
It may not be of a size that was intended
It may take place at a time and location that was not predicted.
Fracking
fracking causes earthquakes
true or false?
