In which Amy Wants to be a Geologist... (long w/ pics) (Myspace Blog)

So this is the story of our geology field trip. I have decided that I want to be a geologist when I grow up. My daddy, the-geologist-who-has-been-stuck-on-sides-of-moutains-and-called-ME-for-help, will be SO freaking proud of me.



This is me. Yes. In my AWESOME Earth friendly Recycled-Plastic-Bag hat. I am playing Geologist. Notice the backpack for holding random rocks (strapped over the chest like any REAL geologist) and the groovey Hippie-chick plaid shorts. Almost as cool as golfing attire. But not quite.



This is Erika. We have Geology together, and we study together. Today she is playing Photographer/Filmographer. She is AWESOME at it too, by the way. Notice her Many-Pockets-for-Holding-Rocks Geologist pants. She likes rocks with one direction of cleavage. This makes her Uber-Geocool. Or something like that.

We went to Lucero Arroyo, an arroyo just off I-10 at Radium Springs. When you get there and look, you don't think that there will be anything to see, but you trek down into quite a significant sized arroyo. It is just inside NMSU land, and they prosecute tresspassers, so if you decide to go and see for yourself, make sure you don't get caught.

The first stop on our mile hike is this particular arroyo cliff.



Notice the two different colours of rock? The purple on the bottom is called Palm Park formation, and it is about 50 million years old. The top is called Camp Rice formation, and it is only about 5 million. I want to live to be 5 million...



The bedding of the Palm Park formation is angled about 45 degrees from horizontal, while the bedding of the Camp Rice formation is horizontal.



This is a nice example of an Angular Unconformity, since there is no explanation what happened in the 45 million years between the 2 types of rock. Plus the colours are pretty.

Next stop: This cute little gentle knoll of rock.



This is called an anticline. It is a little frown shaped formation. Had it been smile shaped, it would have been called a syncline. But it's not, so it's not. So there.

Notice how the rocks in this little outcropping are lining up with each other? No? Well, they are.



This is called imbrication, and it is an indication that the rocks were originally placed here by strong currents of moving water. The direction of the imbrication tells the direction in which the current moved. In this case, from the left to the right of the screen.


Here is an example of a lahar, a volcanic debris flow.



This particular lahar is a part of the Palm Park formation (it's purple) and is made of andesite. Geology Guy says that this means there must have been a volcano here.

Yah, like he knows stuff. Sheesh.


Now we start to see a new rock formation. It is yellow and chunky and is called the Abo formation.



It is actually the oldest of the rock formations we see, having had 290 million happy returns. There is a fault between the Abo and Palm Park formations. This video will show you. And yes, that is the wind. Really.



Ok, so everyone repeat after me... Normal faults are produced by extension.

In case you are lost, here is a diagram...



This is Geology Guy straddling the fault. Purple Palm Park formation on the right, yellow Abo formation on the left. I wonder if I would get to straddle faults if I were a geologist...



A bit later on, we see quite a bit of siltstone (And I figured out what it was, yay me!) with fossil imprints of plants. Here is one, kept large for you to see the fern fossil in it.



This is an example of jointing, rocks that crack and expand without additional movement. It almost looks like a puzzle. Erika and I tried to pry some up to take with us, but to no avail. It just wasn't coming.




Now we are almost to the end of the mile hike, and we discover fossiliferous limestone. There were amazing fossils in this, worthy of a few pics.







Notice that all the fossils are marine? As a Geologist-for-a-day, I can tell you that that MEANS SOMETHING.

Geology Guy said that marine=ocean.


In the end, this is what we figure out. In the Early Permian, there was a completely different set of mountains that have since eroded away, along with an ocean that rose and fell with the change in the ice caps. We had rivers and lots of fern type thingies and marine creatures. The REAL geologists drew up a map, just to make it easier to understand. Notice the detail and professional quality artistry.



Along the way, we saw things like mud cracks and burrows of little mud-dwelling creatures, leading Erika to record this video of my questioning Ms. Huff about the differences between two rocks with different burrows.



I even SOUND like a Geologist!

We also saw a horney toad. I like horney toads, having forced them to spit blood out of their eyes at me as a child, so I am leaving his picture large. No, we did not mess with him. Poor thing has probably never seen so many giants in his life, plus they are an ENDANGERED SPECIES. Yes, for reals. Yes, you should feel guilty for torturing the poor things. Go wash the horney toad blood off your hands now.



(Hija saw this picture and said, "Oh, look at him!! He's so horney!!" *sighs*)

And finally, the part that Erika said just proves that I am meant to be a geologist. We are walking back. There is a small fault sticking a foot or two out of the ground. I jump up on it...



and shout "It's not MY fault!"

I thought I said the funniest thing in the world. So did Ms. Huff. We rolled on the floor laughing. It WAS funny, dammit! Erika, however, just smirked and said it was geologist humour.

If I had known that all it took was stuffing a backpack full of random rocks and being funny, I would have become a geologist it a long time ago.