The North American Plate and the pacific plate created friction by sliding past each other, the tension at the edge of the plates caused the earthquake that measured 7.1 on the richter scale. This is called a conservative plate boundary.
What Are The Causes Of The San Francisco Earthquake In 1989?
The san andreas fault
the pacific plate and the north america plate move
the pacific plate and the north america plate move
Well the epicentre of the earthquake was in Loma Prieta. It measured 6.9 on the Richter scale. So to answer your question, it was simply an earthquake, so there were no causes other than the natural causes of an earthquake.
When two continental plates like north america and trhe pacific plate slided against eachother and that it creates an earthquake, which is called a Subduction zone- where two plates clash against eachother. So its destorying everything in its path.
The epicenter was in the santa Cruz mountains and it measured 6.9. Earthquakes happen when two plates are against each other and trying to move, friction builds up between the two plates in the fault line,and eventually they move slightly and that causes an earthquake. Then the cycle starts again. I hope this has helped x