Saturday, June 13, 2015

The Great Valley! WE FOUND IT!

Yeah. So I grew up watching a mix of 101 Dalmatians and The Land Before Time. I wasn't introduced to Jurassic Park until middle school, so instead of thinking that dinosaurs could be genetically engineered from Cenozoic amber (because yes, the source cited in Jurassic Park is actually far too young for the mosquitoes to have ever seen dinosaurs), I grew up knowing Triceratops as the 'three horns,' sauropods as the 'long necks,' and carnivores as the bad guy. Not to mention the wonderful confusion of having Jurassic and Cretaceous dinosaurs running around next to each other. 

Poor, confused, 4-year-old me.

Not that I'm complaining. Even if it was yet another non-scientific meant-to-be horror movie produced by Spielberg and a complete (yet more successful) rip off of Bambi, it kept me busy for several hours at a time growing up.

Regardless, this isn't about the horrible science behind either of those dinosaur movies. Or how adorable I still think 101 Dalmatians is, for that matter. This post is actually about geology.

Disappointed? Sorry. There's too much bouncing around the internet right now bashing those movies and honestly contributing to all of it just sounds boring.

Instead, let's talk about how weird Utah geology can be. 

We were given a task after work today, since we were all working today. Our boss sent us down to a place called Cedar Mountain, which is a type locality important to geology as well as a popular camping site for our guests.

The reason I brought up Land Before Time is because I took one look at this place and remembered back to those fun, simple, non-scientific days.

"Hey guys!" I yelled to Mac and Kaitlyn. "It's the Great Valley, we found it!"

Quoting Cera in the first movie. In my defense I actually did a paper for a history of paleontology class involving that movie, so I remember it in more detail than I would otherwise. Ironically, right as Cera shouts this about what she thinks is the Valley, a large herd of starving sauropods charges in and devours everything in site. Spoiler alert; they weren't in the right place yet.

I had to make the joke. I mean, look at this place. It looks like it could be it!

Okay, enough joking around now. There's a reason I brought up Cedar Mountain.


 First of all, its a type locality. In the natural sciences, there is a concept of a type specimen, which is basically an individual of, say, a species, that is used to describe what is expected of a given group and thus represents the whole. Generally, it is the first known of a given species, but not always. It has to be a good representative.

 Similarly, geology has a concept of a type locality. This basically means that a formation is named for this site, and the site can be used to represent the expected rocks, chemistry, and fossils in a given layer, and to correlate said layer with other layers. Thus rock formations get their names, such as the Cedar Mountain Formation. This one represents the early Cretaceous period, the home of the Utahraptor, Acrocanthosaurus, and Siats, as well as a few species of sauropod, ankylosaurs, and ornithopods. 

What's even cooler about the geology of this site is how much else is exposed there. 

 To the left is a diagram of the oddity that is going on in the picture to the right. 

 Standing on Cedar Mountain, you find yourself looking out at an anticline. That means that after layers and layers of rock were deposited on top of each other, oldest on the bottom and youngest on the top, the area got deformed by tectonics and the entire area got pushed into an arched shape. Then, since the layers were now elevated, deposition ceased and erosion began with a vengeance from the top down. This leaves the oldest layers of rock exposed at the top as the younger ones are eroded away. Basically, it makes the entire mountain look like deposition happened going backwards in time, but the anticline makes more sense than time reversing on us. 

 And so by walking down the mountain, you go forward in time. 

 Love it. Utah is in a really stable part of the continent (unlike the east coast where we had an entire continent scrape off a lot of our sedimentary rock millions of years ago), so even though the Precambrian rock isn't exposed at the top of this anticline yet (in a few million years it may well be), it is in other ones around the state. Basically, its a walk back in time, a time capsule. 


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My Story (Very briefly...)

Lots of people claim that they wanted to be paleontologists at the age of 3. So did I. The problem is, I never really grew out of it. My third birthday party had dinosaurs. Everywhere. I grew up digging in fossil dirt from Aurora, NC, looking for coral and shark teeth. I practically lived at my local science museums (and still do, only now I get to do research, fossil preparation, and work in collections!) When local paleontologists discovered a dinosaur with a "fossilized heart" (no longer considered such) when I was little, I got to meet the man who led the work. And then, years later a dinosaur bone with soft tissue turned up. I was officially hooked.
No longer was I dreaming about dinosaurs. I was actively pursuing the science behind prehistoric creatures. I didn't want to read about it, I wanted in on the action. So I started working at the museum, and finally going on my own adventures. And thus, I needed a place to share them and maybe inspire others the way I was inspired. I have gone from watching fossils be prepared from one side of the glass at the museum to working on them on the inside of the glass. I am a student working toward my goal. I can finally start to call myself a paleontologist.