"In a series of papers published between 1923 and 1932, J Harlen Bretz described an enormous plexus of proglacial stream channels eroded into the loess and basalt of the Columbia Plateau, eastern Washington. He argued that this region, which he called the Channeled Scablands, was the product of a cataclysmic flood, which he called the Spokane flood. Considering the Nature and vehemence of the opposition to his hypothesis, which was considered outrageous, its eventual scientific verification constitutes one of the most fascinating episodes in the history of modern science."
Victor R. Baker, 1978

In Baker's 1978 paper, he highlights the relationship between the flood morphology of the channeled scablands and the flood channels on Mars. In both cases, cataclysmic floods scoured the landscape, producing deeply incised river valleys, streamlined hills, and other indicative erosional features.
The recent discovery of columnar jointing in Martes Valles, Mars (Milazzo et al., 2009) has strengthened the relationship between the Channeled Scablands, where jointing is readily observable in the Columbia basalts, and our terrestrial neighbor.

Tuesday, July 5, 2011

Physics in GeologyLand

I also am trained in the ways of physics instead of geology, but I have decided to pursue Geoscience in my graduate career. I am fairly certain “Geoscience” means almost whatever you want it to, and I have been toying with the idea of having it include field work despite my very theoretical base in physics. I am happy to say LPSA’s trip to the Scablands has helped to solidify that plan.
Being able to see, touch, climb on, and take measurements of the rocks and processes that we are studying adds quality to our research that you simply cannot find in textbooks and computer modeling. The main subject of our studies in the Scablands (researching basalt columns on Earth to make inferences about ones on Mars) embodies the union of space missions, data collection, and field work that makes planetary science so exciting.
A lot of physics is asking questions- how does this happen? Why does it happen? What is it made of? I learned on this trip that geology is no different. Geology is a mystery that geologists have set out to solve. In the Scablands, we saw a 15 million year old basalt layer lying on top of a 100 million year old granite layer. A passerby may think this is a very pretty contrast, but a geologist asks the question: where are the 85 million years in between those layers?
At first when I saw photos of the basalt columns we were going to measure, I was simply shocked that nature could create something that shape by itself. Now after our trip, I hope that the group’s efforts at characterizing the basalt columns of the Scablands contribute to solving the mystery of exactly how they formed. I also hope that our work can help characterize the basalt columns we see on Mars.
I feel extremely fortunate that I was able to explore the Channeled Scablands, and even more so when I think about the fact that the Scablands are one of very few places on Earth we can see the results of an ancient megaflood and the formations of basalt columns. At the end of a day of surveying our specific sites, everyone on the trip was sure to sit back, think of the larger picture, and soak in the beautiful landscape. It was a good trip indeed.


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