How are earthquakes and volcanic activity related to plate boundaries?
Jun 01, 2009
in
Earthquake Questions
I'm trying to find out how earthquakes and volcanic activity are related to plate boundaries. I believe that composite volcanoes are formed within convergent boundaries and shield volcanoes are formed within divergent bounrdaries. What about earthquakes though? What are the other types of plate boundaries? 10 points to the best answer!
Do hot spots also produce shield volcanoes? Do transform boundaries produce any type of volcano?
Like this post? Subscribe to my RSS feed and get loads more!
3 comments
ichabod40 on June 1, 2009 at 6:41 am
You're correct about composite and shield volcanoes. Earthquakes occur at all 3 plate boundary types, which will produce faulting (offset) as follows: divergence produces normal faults and block/fault mountains (i.e., Nevada), convergence produces reverse faults and thrusting, transform boundaries (the third type) produces strike-slip faults like the San Andreas and Mendocino Escarpment (no volcanoes, though).
tweek on June 1, 2009 at 6:41 am
The subduction zone of an earthquake is the area of intense activity caused by the movement of two plates where one plate subducts beneath the other. There are three types of plate boundaries where subduction occurs: ocean to ocean, ocean to continent and continent to continent.In an ocean to ocean subduction, the plates are pulled apart. In an ocean to continent subduction, one plate is thrust under the other. In a continent to continent subduction, the plates scrape past one another (USGS). An earthquake begins at a contact between two rock surfaces; one side of the fault overhangs the other. If the overhang side moves downward, the fault is normal. If the overhang side moves upward, the fault is reverse. If the movement is along the vertical axis, the fault is a dip-slip. If the movement is along the horizontal axis, the fault is strike-slip. The friction between the two planes of the fault controls its movement or lack thereof. The lower the friction, the weaker the fault and the easier it slips. Fault creep is when the friction is low enough so that the fault may slip constantly and aseismically. Medium friction produces small earthquakes and high friction will produce a fault that will slip occasionally, but with a few large earthquakes (Robinson 60).
wolf on June 1, 2009 at 6:41 am
in the south Pacific there are five islands sitting on a hot spot and Kilauea is a shield volcano.
when plate boundaries are pushed beneath each other they cause volcano's to erupt and cause earthquakes to happen. the other plate boundaries are the San Andra fault line that's the case of the eastern plate rubbing against the western plate that is why there are so many earthquakes in that area .I hope that I've been some help.