Journey Not Quite to the Center of the Earth Strikes Back

For the Unobtainium Falcon to travel inside the earth, it has to have a lot more features than your parents’ minivan. First it needs to be able to travel through the ocean, then it needs to drill through solid rock and then it needs to be able to move through incredibly hot magma that can be thicker than honey.

If you remember my last blog, the crust sits on top of the mantle. Both the crust and the upper mantle have solid rock in them that we need to drill through. Because parts of two different chemical layers share the physical properties, another way scientists divide the Earth into layers is by their physical properties.

The top layer of solid rock that you trip, fall and scab your knee on is called the lithosphere. It includes the crust and the upper mantle.

The lithosphere floats on a layer of gooey, thick, slowly flowing material. This layer is called the asthenosphere. Hopefully you will never trip and fall on the asthenosphere, because the temperatures there are anywhere from 900 degrees to over 1600 degrees Fahrenheit.

The lithosphere is actually thinner under the ocean (somewhere around 50 miles thick) than it is under your feet right now (where it is probably somewhere around 120 miles thick), which is why I’m driving the Unobtainium Falcon through the ocean.

As you can see in my art school trained drawing, there are places where the asthenosphere breaks through the lithosphere. Most of these places are in the ocean floor where the lithosphere is a lot thinner. If magma from the asthenosphere is breaking through in one small place, it is known as a hotspot. A hotspot is what made the Louisville Seamount Trail. If huge amounts of magma are breaking through a long place, it is called a rift or a rise. When the magma at a rise comes in contact with the almost freezing water, it immediately turns into rock. This new rock pushes all the old rock and actually makes the entire seafloor move. The moving seafloor is why the Louisville hotspot made a chain of volcanoes instead of one ginormous volcano. As the seafloor moves over the hotspot, the magma has to pop out in new places and make new volcanoes, all in a line.

I’m ready, so here I go into the Earth in the Unobtainium Falcon.

So that is not the Unobtainium Falcon in the asthenosphere. I actually Photoshopped the Unobtainium Falcon onto a picture of an eruption of Mount Stromboli. One thing I forgot is that when you are drilling through rock or travelling through magma, you can’t actually see anything, because your vehicle is completely covered by rock and/or magma, which is another reason why it is difficult to learn about the inside of the Earth. Luckily scientists like the ones on the JOIDES Resolution know how to read rocks to learn about the earth’s interior. Because of their work, we already know a lot about a place we can’t ever see, unless the Unobtainium Falcon gets much better windshield wipers.

Sincerely,

The Blogfish

PS. To find out what unobtainium is, read this.

 

Comments

The blogfish

I have the legos and a 10 years old...So I feel sure I can get an unobtainium falcon whipped up. What I really, really want though, is a blogfish stuffy. Do I have to troll seamounts to get one, or is this commercially available?
Thanks for the link on unobtainium. Great talking point for when we just can't get that mindstorms bot together the way we planned :)

best,

Julie Karavan

Thanks, Julie! The Blogfish's

Thanks, Julie! The Blogfish's physical creator was one of the scientists who regularly ships out on the JR., Katie Inderbitzen. The Blogfish is not commercially available, but you've probably given her something to think about.

The Blogfish/ Blobfish

Well, with all the cool marine creatures we've seen from the Census of Marine Life, we think the opportunities for cool stuffed creatures are wide open :) We read about how the Blobfish gets stuck in trawlers. Are Blobfish found around seamounts specifically? Are there marine creatures unique to the seamount environment? How does the coring effect the habitat? We went to a lecture on squid at the Wagner Institute last year, and it looked like the speaker went to a seamount to study deep sea cephalopods. See any cool cephalopods?
Best
Julie and Luke

Seamount marine life

Great questions!
Are Blobfish found around seamounts specifically?
Blobfish are deep-sea creatures that are found, not only around seamounts, but also in other deepwater environments off the coast of New Zealand and Australia.
Are there marine creatures unique to the seamount environment?
There are actually many marine species unique to seamounts. In fact, seamounts are like islands, in that each seamount can have species on it that are not found anywhere else in the ocean, because it is too far to travel to another seamount. Scientists still do not know a lot about life on seamounts because they are so deep in the ocean, but they discover new species there any time a marine biology research vessels goes to one of them. Scientists do know that deep-sea coral reefs live on seamounts. There is also a species of fish that is offered in seafood restaurants called orange roughy that is only found on seamounts. The scientific consensus is we are overfishing orange roughy and destroying habitats on seamounts in the process, so I never order them.
How does the coring effect the habitat?
The tops of seamounts are almost completely covered by sand, and based on the camera we sent down, there were not any reefs where we drilled. Lots of fish were curious about the drillpipe, though.
See any cool cephalopods?
Scientists have discovered many species of deep-sea squid, and most likely there are many that make seamounts their homes. We have not seen any squid or octopus with our deep sea camera, but twice at night along the Louisville Seamount Trail, we have seen groups of squid about a foot long alongside the JR chasing flying fish.