Locate Japan on the static map to the right. Along the west coast of Japan, you should notice the dark line that runs up towards Russia and arcs back around Alaska. 1. Based on what you know about the process of plate tectonics, what is the significance
Locate Japan on the static map to the right. Along the west coast of Japan, you should notice the dark line that runs up towards Russia and arcs back around Alaska.
1. Based on what you know about the process of plate tectonics, what is the significance of this dark line, considering its proximity to Japan?
Answers ( 1 )
Not quite sure what you mean. There are two fault lines that run by Japan, one to the west, which actually runs right through the island, dividing it near in half; the second fault line running up to the Aleutian Trench and across to North America and the border of Alaska and Canada, then down the coastline crossing into California and down through a portion of Mexico and into the Gulf of California. This is part of the Ring of Fire, which extends farther, into the southern hemisphere down towards Australia in the west, and along the coast of South America to the east. It is the most active region on the planet for earthquakes. And along those faults there's regular and considerable movement of the plates, which overlap, and the upper plate pushes lower plates down further, they are subducted, or pushed down. That action generates magma, which leads to volcanic activity, but more volcanic activity is noted in more southerly regions.
As to relevance, Japan is very vulnerable to large earthquakes, as was particularly noted in 2011 when the massive 9.0-9.1 earthquake struck just 45 miles/72 km from the northern coastal region. Japan, because of the considerable tectonic activity, on average experiences 5000 minor earthquakes per year, many measuring under 3.9. But to note, just this past 7 days from the answer, Japan has experienced 13 earthquakes - 11 measuring from 4.2 to 4.9, and two at 5.4. Japan and the Pacific Islands are a volatile region for earthquakes.
Now, I'm not a geologist or seismologist by any means, but it became a personal interest after living in southern California, having moved there just two weeks before a huge earthquake in 1971, and experienced quite a few since then. So, to clarify, I'm not sure what information you are hoping to receive, but generally, the region you ask about has more activity because of how the plates sit on each other - there's considerable and regular movement of the plates, and that generates earthquakes, and volcanic activity. If you might imagine drying dishes after dinner, and laying dinner plates upside down on a towel spread across the counter - you will get some movement of the plates from any vibration caused by movement - like hitting the counter, plates will move; if you slam a door, all the plates may start shaking,and shift positions, and you bang hard into the counter, some plates may fall. That's essentially how that works.
7 days on the Ring of Fire - all earthquake activity, 6/21/21 for previous 7 days - the fault lines in red, as you can see on either side of Japan, and the one line you mention, which are multiple-named faults, in order, Izu-Ogasawara Trench, Japan Trench, Kuril-Kamchatka Trench, Aleutian Trench in over to the Gulf of Alaska.
.Here's a USGS interactive map that you might want to check out, you can see the regions and faults in relief.
https://usgs.maps.arcgis.com/apps/webappviewer/index.html?id=5a6038b3a1684561a9b0aadf88412fcf