This week we are exploring Plate Tectonics and how important it is to know the location of the plate boundaries, and how it is closely related to some natural hazards, like volcanoes or earthquakes.
In the US, the NOAA map below shows how the Easter part of the States is a passive margin, and the Western side of the country is a very active one, with the Pacific Plate, Cocos, Juan de Fuca plates connecting to the North American plate. Not a surprise we are on the ‘Ring of Fire’, where a lot of the volcanic and seismic activity happens!
Closer to home, the transform plate boundary called SAF (San Andreas Fault) is responsible for most of the shaking. These plates (North American and Pacific) are slowly moving past one another at a couple of inches a year; about the same rate that your fingernails grow! Our amazing SAF is also a right strike slip fault.
Of course, there are a few exceptions, like the activity of Hawaii within the Pacific plate (hot spot) or the New Madrid area (ancient rift) within the North American Plate, both not at plate boundaries, but that will be another post another time...
We might not know when events like volcanic eruptions or big earthquakes will happen (a lot of these happen underwater...), but if you know your Tectonics, you definitely know where the (mostly) do!
I really enjoyed learning, from your blog, about the many different plate boundaries that are represented in the United States. Of course, that is probably to be expected in such a large country. The United States shares the similarities of having many earthquakes and some volcanoes, with the country of Iceland. I also found it interesting when I was doing some research about divergent boundaries that this type of boundary usually occurs in the ocean, however they can occur on land as well. In my search for an example of this I found the Rio Grande Rift which stretches from Mexico into the United states probably at least as far as Colorado. Very interesting!
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