Tuesday, January 24, 2012

Update on Rio Grande Rift

In my last post on the Rio Grande Rift, I was hesitant to say if it was still spreading. I don't have access to all the journals, I had heard some conflicting opinions from a few geologists, and my cursory search didn't find a lot of information. However, the January issue of Geology did have a study dealing with exactly that. And guess what, the rift is spreading, about one inch every forty years, so that's pretty cool. I can't wait to read the full article (once I get my reimbursement check from my school and can afford to pay my student dues to the GSA).

However, due to my status as a college kid with limited funds; I unfortunately did not read about this from a cool source, instead I learned about it from this Yahoo News article which didn't even turn out to be an intelligent source. It doesn't start out bad, but then it starts saying a few things which demonstrate a lack of real understanding about geology. First off, it says this is a very slow pace (direct quote is "paltry rate", and it is compared to Usain Bolt or a landslide or really anything we deal with in our day to day experience. However, this is geology so almost everything happens slowly, so if you are going to say it happens slowly compare it to another plate. It is moving slowly compared to other plates which can move around 2.5 cm a year, while this rift is widening around 1 mm per year, 1/250 slower!

Then, the author makes a comment about controlling the expansion which seems odd and raised a few questions. First, why, it is barely moving and at those rates shouldn't disrupt humans at all; however, stopping the motion would just mean all the energy is pent up and then released when whatever is keeping from moving fails, causing an earthquake. Second, since when is it the goal of geology to stop plate tectonics? I've heard of geo-engineering projects, but I don't think anybody has ever even thought of something this large.

The article did leave a few questions I had unanswered. Do the scientists know if this rate is accelerating, decelerating, or remaining the same? This would be nice to know; is another East African Rift opening up in Southwest America or is this movement dying out. I would like to know this because there are inactive volcanoes around the rift (including near Albuquerque) and it would be nice to know if they might wake up. In addition, does this movement have any implications for earthquakes around the rift, especially in the Sandia Mountains where New Mexico's largest city sits on loosely compacted sediments from the mountains surrounding it oh and an aquifer. So as my Intro to geology professor once (somewhat gleefully) pointed out, should a large earthquake hit the city, the soil would probably liquify and consume large parts of the city.

By the way, I'm not too worried about earthquakes or volcanoes as a result of the spreading; however, it is not a stretch that some people who live in Albuquerque might be, and it would only take a extra sentence worth of effort to soothe these fears. Questions like this is why you should talk to a scientist before you publish a story because now I have to wait to gain anything valuable until I either bum the latest copy of Geology, or get the money to look at it online. Thanks Yahoo News, for all the effort you put into the story.

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