By incredibly good luck I’ve been spending lots of time in Hawaii lately, on business no less. I stay in this unbelievable house.
One really gets the sense of being out in the middle of the ocean in Hawaii, at least I do. Then of course it is necessary to have a look to see what this place is really all about.
Ok, so the Hawaii we think of is way down at the right bottom of the blue gravity boomerang. It is just the latest in a series of seamounts that has been continuously burning a hole in the ocean floor for about 85 million years. The very oldest one is up near the strange inflection point where the Aleutian Trench meats the Eurasian trench system.
The pronounced bend at the Mendocino Fracture Zone technically separates the Emperor Seamounts from the Hawaiian chain. Although the volcanic ages of the islands move smoothly through this bend, something important happened here. The islands are smaller and more sparse and they haven’t pushed the crust down enough to create a gravity low. You can see they have been offset a bit
Before they ran into the Mendocino Fracture Zone, both the hotspot and the ocean floor were moving. You almost get the feeling the fracture zone stopped it. After the fracture zone towards Hawaii the trend is normal to the direction of the ocean floor movement, and the hotspot may not have moved very much as the ocean floor above just sailed by. Hawaii is the end of the line now, but it will be just a few more islands in the procession in due time.
Gotta get back to work, but don’t feel too sorry for me…
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