The Basic Geology of Hawaii by Kayley Rolph

Hawaii is known for it's overall awesomeness, but there is much more to Hawaii than good surf and beautiful beaches. The Hawaiian islands are volcanic islands ,as you well know, but they are no where near the edge of a tectonic plate, where most volcanic activity is situated. This was puzzling for the early geologists who studied Hawaii, but they have figured out how the Hawaiian islands formed and explained the basic geology of Hawaii.

The Hawaiian islands are far away from the edge of the Pacific Plate, where most of the volcanic activity is. Tectonic plates are irregular and unpredictable, they have thin spots in the crust and thick spots, they can spontaneously change direction when it collides withe a nearby plate. A hotspot is a weak spot in their earths crust where magma can push to the surface. Since the Pacific Plate is always moving, so is the hotspot. 

 

The Hawaiian islands are all shield volcanoes. The rock that they are made of low viscosity magma or fluid lava. This makes the Hawaiian islands supper wide and not very steep, like a shield. The older Hawaiian islands have been eroded so much that some don't even break the surface of the ocean any more. Since Hawaii is the newest island, it is also the biggest because it hasn't had time to erode as much as the others.
 

If you were to look at a map of the chain of islands created by the Hawaiian hotspot, it looks as though it just started popping up islands in a different directions. The hotspot that created Hawaii also created the Aleutian islands that streach southwest of Alaska and the Emperor Seamounts, which connect the Hawaiian and the Aleutian islands. The pacific plate was moving Southwest at that time but it has changed direction two times to get to its current course of southeast movement. More shield volcanoes are developing southeast of Hawaii and some will break the surface soon.

The Hawaiian island's geology is facinating and unique. I find it amazing that one weak spot in the earths crust could open up an opertunity for three island chains, whole cultures, ecosystems and much, much more. Bye, for now.

By Kayley Sienna Rolph

P.S. I have some diagrams to help illustrate and explain the geology of Hawaii.