February 8, 2011

Happy Birthday, Jules Verne!

Posted by Evelyn Mervine

Movie poster for “Journey to the Center of the Earth.” Image taken from here.

David Bressan over at the History of Geology blog reminded me that today is the birthday of Jules Verne, one of my favorite authors. Happy Birthday, Jules!

Even more excitingly, on his blog David posted a trailer for the 1959 Disney movie “Journey to the Center of the Earth” starring Pat Boone. This is my all-time favorite movie. I first watched this movie as a young child at my grandmother’s house. One day, I found the movie in a pile of VHS tapes of children’s movies that my grandma kept to entertain her grandchildren. I watched the movie and loved it. From then on, every time I visited my grandmother’s house I had to watch “Journey to the Center of the Earth.” You know how children often have one book that they insist on reading every night? Or one movie they insist on watching all the time? Well, my movie was “Journey to the Center of the Earth.” If I stayed with my grandma for a week, I’d watch the movie every day. I think my parents purposely did not buy a copy of this movie because if they had then they’d have been forced to watch it even more often.

Many years later, when I was an undergrad at Dartmouth, my mom bought me “Journey to the Center of the Earth” on DVD as a Christmas gift. Perhaps that Christmas gift was the inspiration for the introduction to a paper that I wrote back in undergrad about  hafnium (Hf) and neodymium (Nd) isotopes. Here’s a snippet from the introduction of that paper:

Contrary to the portrayal in Jules Verne’s classic novel Journey to the Center of the Earth, in which a group of scientists reach the center of the Earth by spelunking down a very deep cave, humans have barely scratched the surface of our planet’s outermost crust. Remarkably, almost all of the adventures that seemed so fantastic when Verne wrote about them in the late 1800s have become a commonplace part of human society. Inspired by the imaginings of Verne and others dreamers, humans have developed technology that allows people to travel around the world in far fewer than eighty days, dive far deeper than 20,000 leagues under the sea*, and soar high above the Earth. At least one Verne tale is still a dream, however: humans have not journeyed anywhere near the center of the Earth. In fact, the deepest hole humans have drilled is 12 km deep, a mere 0.2% of the Earth’s 6378 km radius (1). As scientists cannot directly sample mantle or core material, they must rely on other methods to learn about the physical and chemical characteristics of the Earth’s interior.

One of the methods modern scientists use to learn about the chemical composition of the Earth’s interior is the analysis of isotopic compositions in rocks on Earth’s surface. Geochemical analysis of radiogenic Hf and Nd [and other] isotope ratios in erupted lavas is a powerful tool for examining the processes governing the geochemical evolution of magma deep within the Earth’s mantle. Isotope compositions and their ratios are minimally affected by the immense physical stresses imposed at
great depths in the Earth’s interior, the processes of magma upwelling to the crust, and the final eruption at the Earth’s surface. Therefore, these analyses can be used to infer the compositions of the igneous source material as well as how these sources mixed and melted to form the rocks on the surface. Combined with major and trace element data, Hf and Nd isotope ratios can even be used to determine the degree of melting that occurred.”

If you’re curious about the rest, you can read the full paper here, but please keep in mind that I wrote this in 2004 as a very young geochemist and that DUJS is a non-peer reviewed, undergraduate science journal.

If you like bad geology movies, go purchase “Journey to the Center of the Earth.” This is a bad geology movie at its best– the geology is laughably ridiculous, the special effects are sensationally awful, and the story is wondrously entertaining. If you’re like me, you’ll watch this movie several times a year, so you won’t want to have to order it from Netflix every time (sadly, it is not available on streaming). And make sure you order the 1959 version with Pat Boone. The 2008 version with Brendan Frasier isn’t nearly as good.

*Note that this is an error in my paper as 1 league ~ 5.6 km. So it is clearly impossible to dive 20,000 leagues in depth since the deepest point of the world’s oceans is only ~11 km deep at the Mariana Trench. In the title of his book, Verne is referring to the horizontal distance traveled under the sea, not the depth.

“Journey to the Center of the Earth” movie shot, image taken from here.
Movie poster for “Journey to the Center of the Earth.” Image taken from here.

Various scenes from “Journey to the Center of the Earth.” Image taken from here.