Team Members

Nathalie Cabrol, NASA Ames and SETI
Edmond Grin, NASA Ames and SETI
Ingrid Ukstins Peate, Geoscience at the University of Iowa
Guillermo Chong Diaz, University Catolica del Norte
Renee French, UC Santa Cruz
Kelli Parsons, University of Iowa
Jen Piatek, Dept. of Physics and Earth Science, Central Connecticut State University
Sarah Byram, University of Iowa

Introducting Renee

Tuesday Nov. 25, 2008:

My name is Renee and I just graduated from UCSC with a BS in Earth Science, concentration in Planetary Science. I got involved in this project by talking to one of my professors who got me in contact with Nathalie Cabrol. Luckily, she had just submitted a proposal for an EPO which was about Young Women in Science and I was also working on one of her other projects dealing with spherules found in the Salar Grande, Chile.

I feel very lucky to have been given to opportunity to come to Chile, especially to do research, and I look forward to the next week! Do what you love, love what you do.

Travel to Iquique

Tuesday, November 25- Travel to Iquique

Today we traveled from Antofagasta to Iquique, which is about a 5 to 6 hour drive. We left around 11 am in a 4 door ford truck. It looked fairly rugged for the traveling we would be doing. We drove up the coast the entire way, which was wonderful. The ocean was to the left, and the mountian range was to the right. It was truly beautiful however the scenery didnt change much. I've never seen anything like this before in my life (no ocean or mountains anywhere near Iowa...) so I didn't want to close my eyes and nap. But if I did, I would open them to a different variation of 'Ocean on the left, tan mountain on the right'. Fine by me. The road was fairly twisty so I got a pretty bad headache, but it was well worth it. Got to the hotel around 5, went to dinner around 8, and slept for the next day.

Fieldwork Day 1

Iquique, Wednesday, November 26

The first day of fieldwork for the Planetary Spherules Project 2008 went well – we had a small crowd of Renee French, who has just finished her undergraduate degree from UC Santa Cruz, Kelli Parsons, a second-year undergraduate Geoscience Major from the University of Iowa, myself (Ingrid Ukstins Peate), an assistant professor in Geoscience at the University of Iowa, and Aristides, our driver. The rest of the team, Nathalie Cabrol, Edmond Grin (both from NASA Ames and SETI), Guillermo Chong Diaz (University Catolica del Norte, Chile), and Jen Piatek (Central Connecticut State University), arrive in Iquique this evening and will join us in the field tomorrow.

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Renee and Kelli are participating in fieldwork as part of our NASA-funded education and public outreach project, Young Women in Science. This project is designed to encourage women in the early stages of their education to pursue a career in science by providing them opportunities to do fieldwork, conduct research, and present their work at international meetings, all while being mentored by women scientists. It’s already interesting having them in the field together, because they have very different backgrounds – Renee has just finished her bachelor’s degree while Kelli is just starting out on hers. They provide a nice contrast to each other, and a good check for me, since I need to remember to explain the basic principles of the field geology we’re doing, like measuring strike and dip, mapping outcrops and sampling for geochemistry. We spent our first day studying the volcanic rocks to the east of our field area, where last year I had found deposits that looked like explosive volcanic material. I had a few questions I wanted to answer this year: Were these rocks from an explosive eruption? How large was this deposit? How did it relate to the geology of the rest of the field area? We confirmed that these rocks formed from explosive volcanic activity, mapped out the distribution and also studied the changes in texture of the unit over the field area. We saw some important outcrops that showed us how the different types of rocks were related to each other. We answered some key questions today that had been left unsolved from the last field season. It was good to start the project with some well-defined goals, and also good to have a very successful first day in the field solving accomplishing these goals. Let’s hope the rest of the PSP continues along the same successful path!

Salar Grande

Wednesday, Nov. 26, 2008:

Today we went to Salar Grande and explored the northern portion of our field area: took bedding attitudes, mapped contacts and fault planes, investigated various volcanic flows and fault scarps. We found that there is a portion of limestone that is truncated by a fault on its western side, consequently surrounding it in intermediate to mafic volcanics. To the south of this limestone lense we found two different types of volcanics: lava, which is more vesicular, and pyroclastic flows, with clasts ranging from a few centimeters to 10 centimeters. We then headed to the fault scarp which is hypothesized to have cut of the source of the spherules observed in the field area. Overall, a very windy day and a good introduction!

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Checking out the Big Orange Mountain

Wednesday, November 26 - Field Day 1

Woke up today at 7:50am and ate breakfast at 8 am. Saddled up the field gear and the food for the car and were off. We drove about an hour to get to the road up the mountain, then drove on up. This part was a little scary for me, because i was on the right side next to the sheer cliff. Now im not terribly bad with heights, but If youre window seat going 60 km/h on a road that has a 1000 foot drop, no guard rail, and about 2 feet of shoulder? ....you (I certainly) get a little nervous.

Our driver Arestides is very friendly, fun, and puts up with our intermediate spanish. We finally get to the salt flat (after some extreme S curves followed by extremely straight road) and our first location: the Limestone Outcrop. Now we didnt know this was a limestone outcrop (formerly big orange mountain) until we climbed it (whew) and smashed a rock and put acid on. It fizzed, which lead us to conclude it was limestone. Ingrid filled us in about the 'deal' with this area and what we were looking to find, and I was taught how to calculate the strike and dip of strata. After further examination we concluded that the overall mountain was a form of micrite (mud layers and limestone layers I believe) so I grabbed some samples of those two beds. We climbed down and located where the igneous rock intersects with the limestone on the west side, and again on the east side, and also found some faults going through the limestone bed. This poor outcrop was getting 'sheared to shreds' basically.

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Afterwards we went South to the Igneous area and tried to identify the strike and dip of that strata, and locate where the clastic material intersects the basaltic lava material. We seemed to get a pretty good idea and drew that outline on our map. Took down some GPS points as well as strike/dip measurements and should be able to get a better understanding of the area.

Finally we got a ride all the way up to the huge fault scarp to the west (extremely visible on the map). It is also the windiest place I have ever been in my life. Lots of 'first in my life' experiences with this trip, its very exciting. Ingrid told us about the area, the fault, the spherules, previous expeditions to the area and what they were aiming to get out of the fault scarp (possible terraces?). Now we have a good overview of what to work on (and look for!) with the spherules and how to tackle the fault scarp in the future. We got back in the truck and zigged and zagged boulders on the way down to the main road. It was then that I understood the significance of a high bedded truck for our trip: to drive over the foot large boulders! In all I'd say that was a pretty good first ever field day for me. I'm looking forward to the rest!

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Happy Thanksgiving

Thursday, Nov 27, 2008:

Happy Thanksgiving! I woke up today not feeling well which lasted pretty much all day, but I stuck it out and I'm glad I did. Today Guillermo, an infamous Geologist who knows everything about Chile, gave us a little history about the geology and a tour around Salar Grande. There are 4 sets of Volcanic Andes in Chile, ranging from Jurassic in the west to Holocene (present day) to the east. Shallow sudbuction off the coast is "sucking" the continental crust into the ocean at a fairly fast rate (geologically speaking of course!).

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The average thickness of the salt in Salar Grande is 70 meters, with some places up to 120 meters thick, and a purity of at least 99%. Guillermo took us to an abandoned mine where we were able to see the perfection of the mined salt. We even found some with radioactive sodium, which showed up as a stunning cobalt blue. Punta Lobos, which is one of the active mines, exports 6 million tons per year, mostly used for roads in the winter. Still, that is an amazing amount of salt!

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We also looked for the source of the spherules found on the western, and now portions of the eastern, side of Salar. We ended up finding volcanics with spherules in them, but they were float in what looked like a drainage so who knows where they actually came from. The hunt continues!

Best Rock Man in Chile

Thursday- Field Day 2

Today we got a tour from Guillermo, probably the most intelligent man on rocks in Chile. We stopped by the ocean and he told us about the faults, the old andes, their formation/composition, etc. Then we drove up to near the limestone crop and stopped again to let Guillermo fill us in on the mines (who owned them, how the operated, etc) which was really interesting to hear.

The salt here is 99.9% pure which is incredible. We then went south and crossed the salt flat which was about 20 minutes of a severely bumpy road. By far the bumpiest road i've ever been on (another 'first life' thing) to check the other side of the salt flat for more spherules. Guess what; we found them. This was 'good trouble' according to Natalie, which had to mean that it would put another variable into our equation, but would just be one more piece that we would know about in the end... I assume.

After the spherule exploration we traveled even FARTHER south to an abandoned salt mine, maybe 40 or 50 feet deep, with the tools and everything still in it. Guillermo told us it was abandoned because the salt was not pure, and to look for blue salt. We found some salt that had bright navy in it, and he told us it was radioactive sodium which would be, an obvious reason, why the mine could not continue and be profitable. I certainly wouldn't want blue salt, let alone radioactive salt on my roads or table. We looked up the half life of sodium; its maximum is 2.6 years, and considering this has been an inactive salt flat for about 12 million years, I think we're okay.

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On our way out of the salt mine we stopped at a hut and Guillermo talked to a man who lived there. He said that a man comes by once a month to bring him food, but we gave him some fruit to have. Living off spaghetti isn't too fun. That was the last stop for the day, so we crossed the horribly bumpy salt flat and headed back home. It was fun to get a tour and history of the area as well as explore it.


Fieldwork Day 3

Iquique, Friday, November 28

Well, we missed Thanksgiving dinner yesterday with turkey and cranberry sauce, but we had a can of chicken-flavored potato chips instead, which turned out (not too surprisingly) to be a poor substitute for the real thing.

Nathalie, Edmond and Guillermo spent yesterday and today in the field with us, and we took advantage of Guillermo’s seemingly unlimited knowledge of Chilean geology to take a tour of the region with him. We had an impromptu stop at an old salt mine in Salar Grande yesterday, where I quickly put Kelli to work (see photo). Salar Grande is some 34 by 4 kilometers in size, with up to 120 meters thickness of salt, up to 99. 5% pure NaCl. A large amount of this salt gets shipped to the US for use on highways, and I am sure I will be seeing some of it again since it’s started snowing in Iowa already.

We did a little exploration of the area yesterday, visiting spots on the eastern side of the salt flat that we had wanted to get to last year, and found some interesting new geology. We also came to realize that salt doesn’t make for the smoothest ride, and the road over the salt flat was quite a bit bumpier than it looks. Today we spent time in our field area on the western side of the salar, near the Coastal Range of mountains, defining the outer limits of our field area. We split up into groups and traced out different units, sampling important rocks along the way. It was a productive two days with Guillermo, Nathalie and Edmond. They return to Antofastaga this evening and Jen, Kelli, Renee and I have two more days of science ahead of us.

Kelli_salt

Ciao,
Ingrid

BEWARE

Friday, Nov. 28, 2008:

I didn't go in the field today because I wasn't feeling well. From what I heard we looked for the northern cut-off point for the spherules. Be wary of fruit/vegetables and meat! Especially if you have a weak stomach (like mine).

Simple Day of Mapping

Friday- Field Day 3

Today was a fairly low key day which was a nice contrast. The goal today was to map the northern boundary of the spherules, so we drove up the side of the mountain, stopped and looked around. Ingrid and I went off to the left to walk up, over to the fault, then back towards the trucks. We got a few GPS points where the northwestern boundary was. After we all reconvened, we drove up towards the north, stopping periodically to check the terrain out. All in all it was a fairly simple day (compared to the others) but still had its importance with the spherules.

Renee Arrives and More Mapping

Saturday- Field Day 4

You could say today is the first day for my and Renee's project. Today and tomorrow we get to map out the terraces and collect rock samples to get an overall impression of the rocks from the different parts of the mountain.

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There are 5 terrace locations in total: Terrace 1 is flat, 2 is the ridge, 3 is the flat above that, 4 is the top of the fault on the east side, and Terrace 5 is the approximate elevation on the west side of the fault. I was called the 'Jefa' (chief) and got to navigate the stopping locations for each of the terraces, which was super amusing to Arestides who continued to call me 'la Jefa' the rest of the day. Because we were all taking it easy these next few days and there certainly is no hurry or time constraint, we only did Terraces 1, 2, and 3 today.

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Overall we had a fairly successful day, though the rock types in terraces 2 and 3 vary quite a bit. Because they vary so much, we had to crack a lot of rocks (to make sure we didn't discover new ones) which usually meant a lot of 'shrapnal' and bits flying off into your face. Its also much easier to break thinner more planar rocks than rounder ones. This can be deceiving however when you see a 'flat' rock that turns out to be quite massive after you discover 3/4 of it was buried in the dust. I've gotten pretty good at the 'one crack swing' though! More practice tomorrow for sure.

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Easy Day of Field Work

Saturday, Nov. 29, 2008:

The goal of today was to get samples from each of the terraces seen in the western portion of Salar Grande. The terraces consist of mostly mafic volcanics rich in feldspar and pyroxene. Some terraces have about 10-15% felsic volcanics rich in epidote. Overall we were able to collect about 7-12 samples for each terrace so we can later compare the different types of rocks at each place.

On our way back to Iquique we stopped at Los Verdes, a place on the beach with lots of epidote. We peaked at the tide pools, where Ingrid was poking at the marine life, and collected some great epidote samples (good crystal structures!). Overall, a relatively easy day in the field with a lot of work to do when we get back to the states.

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Fieldwork Day 4 + 5

Planetary Spherules Project: Fieldwork Day 4 + 5 (Saturday & Sunday, November 29-30)

With 2 days left in the field, I decided to give Kelli and Renee a little hands-on research experience. The best way to learn to do science is by actually doing it, and what better place to start than with a fabulous field area like this one? “Las Chicas” became “Las Jefas” (which amused Aristides to no end). The goal for the remainder of this project was to characterize the variations in types of volcanic rocks that make up the fan deposits over a large part of our field area. As “Las Jefas” they were in charge, and responsible for evaluating the field area, deciding what constituted different fan deposits, scouting sampling locations, developing sample protocol, taking the samples, field notes, sample labeling, and generally deciding what to do, when, where and how to do it. They rose to the challenge, and designed a well-reasoned project and implemented a significant part of it today. Hey especially liked being the ones to give driving directions, with a point and a little nod, and a ‘Let’s go over there and look…’ to Aristides.

We, Jen and I, relegated to non-Jefas for these two days, tagged along and answered questions when necessary, but basically hung back and let them get on with it. This was the second year of research at Salar grande, and I arrived with some well-defined ideas of what we should be looking at. We accomplished everything I wanted to study, and even more, thanks to hard work, some toughing it out when people felt under the weather, and a lot of interest and motivation from Renee and Kelli. Great job Las Jefas!

This is the first time we’ve had undergraduates in the field as part of this project, and coming to Chile for fieldwork (in Kelli’s case her first-ever fieldwork) was a big step for them. This has been a great success and I find I’ve finished this part of the field expedition with a sense of accomplishment, and am looking forward to the next project with great anticipation.

Kelli_n_Renee_Day5
Kelli and Renee

Last Day

Field Day 6 - Sunday

Today is the last day of field work. We woke up a little later than usual and made our way out to the field. Today we had Terraces 4-6 left. This left us the very top of the fault scarp, the valley between the old range and the top of the scarp, then a slight way up the old range. We got a good range of samples, still finding a lot of mafic rocks in general, until we got to the valley and the old range. Here we found crystals of white and green minerals (about 5-10 mm in size at the largest), though the variety in the valley and especially the old range were very limited (20 ish samples in the terraces down to around 7 or so in the old range).

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It was so windy at the top, maybe around 40 or so mph that we didn't stick around long and had a quick thorough day. Jen took some great panoramics at the top of the fault scarp and Ingrid busted out the sledge hammer on some angry rocks, but otherwise it was a typical day. It was a bummer to hear Ingrid say that the work at this site was pretty much done and that it was questionable whether we'd come back, but for the incredible things I learned (first hand, and in CHILE none the less!) it was a wonderful experience. It was really neat to come across some new types of rocks, and I'm REALLY excited to take them back to the lab and get a good look at them!

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Introducing Sarah


My name is Sarah Byram and I’m in the final year of my BS degree in Geoscience at the University of Iowa. I am currently working with Ingrid Peate on a project examining some of the samples she collected last year at Laguna Lejia during field work for the NASA High Lakes Project. I was lucky enough to be offered a chance to participate in field work for the NASA Planetary Spherules Project this year, and so on December 1st I boarded a plane in Cedar Rapids, Iowa (late, due to a little snow and ice) to start my trip to the Monturaqui Impact Crater in the Atacama desert in Chile. After stops in Dallas and Santiago (including a beautiful sunrise view of the Andes from the plane window), I finally landed in Antofagasta, Chile on December 2nd, just less than 24 hours later.



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Sarah getting to know her outcrop

Monturaqui Impact Crater Field Day 1

Planetary Spherules Project: Monturaqui Impact Crater Field Day 1(Tue-Fri Dec. 2-5)

We find ourselves here in San Pedro de Atacama after a busy few days in Antofagasta. On the 2nd of December we had a whole-scale student swap, dropping Kelli and Renee off at the airport and picking up Sarah Byram at the same time. Both Kelli and Renee made it back safely, and Sarah arrived after what must have been close to a full day of travelling looking bright and fresh. I gave her the option of napping (which I would have probably taken had it been me) but she was a trooper and decided to come out for the afternoon and run some errands with me. We had the next day in Antofagasta free as well, and on the Friday morning loaded up our mini-bus with all our field gear and belongings and drove across the Atacama Desert to head for San Pedro, the Andes, and our next area of interest, Monturaqui Impact Crater.

This was the second time I’ve made this trek from the coast to San Pedro this year, because I was also on the High Lakes Project expedition with Nathalie, Edmond and Carlos, which ended just a few weeks ago (http://cabrol.seti.org/HLP2008/HLP2008.html), and we started that expedition with the same bus journey through the desert. This time our goal was not the summit of the lovely volcanoes which frame our view to the east, but a crater formed by the impact of a meteorite approximately one million years ago.

The two new members of our PSP team are Sarah, an undergraduate at the University of Iowa working with me on her senior honors thesis, and Carlos, a medical doctor on this part of the project as a ‘just in case’ precaution because we will be working in some remote areas. We arrived in San Pedro, a vibrant and historically rich town with wide streets and charming adobe buildings, after roughly a four-hour journey. Our first day in the field, Friday the 2nd, consisted of a stroll around the crater, which is about 400 meters in diameter, to get me re-acquainted with the geology and introduce Sarah to the details of her new field area.

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Sarah with her first sample

After the obligatory 30 minutes of awe and admiration for the spectacular line of Andes volcanoes providing a backdrop and just plain coolness of being on the rim of a meteorite impact crater we managed to pull ourselves together and tear our eyes away from the view long enough to start our survey around the crater in a counter-clockwise fashion. We are in the southern hemisphere, after all, and if water goes down the drain counter-clockwise here, then it seems fitting that geologists ought to loop around a crater counter-clockwise as well. We got a little distracted about a third of the way around when we found ourselves in a dense field of ‘impactite’ – rock formed from the fusion of melted rock and melted meteorite. Monturaqui is special because the impactite here contains spherules of metal thought to be wee little blobs of melted meteorite. Sarah was delighted with her first sample (see photo) and it made a great start to this project to find such spectacular rocks right at the start. We’re planning a long-distance traverse to sample for metal and glass spherules in the distal ejecta blanket over the next two days, which will take us away from the crater itself but will let us stretch our legs on some hiking in this spectacular area.

Ciao,
Ingrid

Searching for Impactite

Tuesday and Wednesday, Dec. 9 and 10

Since Ingrid and I finished our transects and David got his granite samples, yesterday the three of us decided to devote our time to search for impactite. This involved spending the better part of the day crawling over angular granite and rough ignimbrite gravel, searching inch by inch for small black, vesicular, glassy impact melt. The day got off to a slow start, since time seems to slow down a little when you’re not actually finding the rocks that you are looking for. The three us of picked up near the outer edge of a lobe of ejecta that Nathalie, Edmond, and Carlos had mostly covered the day before. We worked our way horizontally around the outside of the crater, and it quickly went from slim pickins’ to essentially no melt rock at all. We crossed over a swath of ignimbrite gravel that was completely devoid of impactite. After a reenergizing lunch break we continued on around the side of the crater, still hoping to find even one tiny piece of melt. We worked our way into a patch of granite gravel and suddenly I caught a glimpse of a little black rock that I knew immediately was the impactite we were searching for. As I leaned over to pick it up, I spotted another piece, and then another even bigger piece. Pretty soon all three of us were picking up melt rock left and right. The lobe had very distinct boundaries, and was small enough that its width was within the error margin of a GPS point in the middle. For the rest of the day we scoured this little patch for impactite, quickly filling a sample bag. Ingrid found many pieces in my footsteps, turned over as I walked up and down the slope. The ground was literally covered in impactite.

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Sarah at Cerro Overo maar with Volcano Chiliques in the background

Today we picked up where we left off yesterday, this time with Nathalie, Edmond and Carlos as well. The latter three continued the search that we started yesterday in the lobe of ejecta we discovered, while Ingrid, David and I moved further around the crater to see if there were any more undiscovered ejecta lobes. Being the impactite picking experts that they are, Nathalie, Edmond, and Carlos had no trouble finding large pieces that we had missed the day before. Rumor has it that Monturaqui impactite sells for about 50 cents per gram on the internet, so if we weren’t so into science we could make a little cash off of our collection. There is geochemistry to be done however, so there are bigger plans for all these bags of rocks. Ingrid, David, and I found a few more pieces today, but nothing like the patch from yesterday. We finished the day a little early to have some extra time to rest up. After that much deserved break, and some delicious ice cream for dessert, we’ll be ready to go again tomorrow.

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Sarah at Laguna Lejia with Volcanoes Aguas Calientes and Lascar (r to l) in the background



Monturaqui Impact Crater Field Days 2 & 3 (Sat & Sun Dec. 6 and 7)

Sarah and I spent the weekend surveying out to the west of Monturaqui. Our goal for this particular project was to collect a set of samples from the crater out to 3 kilometers to be able to look for microscopic metal and glass spherules generated in the meteorite impact that formed Monturaqui. The impactite contains small metal beads that are thought to be melted meteorite mixed into the glass that is melted target rock (otherwise known as the ground unfortunate enough to be at the site of impact). In this crater, the target rock consists of a thin layer of ignimbrite (an explosive volcanic rock) overlying granite, and last year we discovered that the granite contains veins of hematite, which may provide a terrestrial source for some of the metal found in the impactite. In order to study this in more detail we’d like to have a set of samples of these metal and glass spherules not just from the crater impactite, but also farther away.

To achieve this survey Sarah and I have spent the last two days walking 3 kilometers from the crater, and for every sample site we collect material to take back to the lab to process for glass spherules, and Sarah collects a magnetic sample to try to catch as many of these microscopic metal spherules as possible. This involves moving all the large rocks from a patch of ground about a meter square, running a magnet over that area and collecting that material, then scraping all the rocks off the surface and running the magnet back over to get any more of the magnetic material. Troubleshooting becomes necessary when the plastic bag the magnet is in gets a hole in it, and all that lovely magnetic material sticks directly to the magnet. Our survey was highly successful in terms of collecting sample material, and now the part of science many people might not appreciate is that we have to wait months for the samples to be processed in the lab before we can learn if we have those glass and metal spherules we were looking for. Patience is a good thing to have at times like these.

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A good magnet works wonders

Meanwhile, back at the crater Nathalie, Edmond and Carlos have spent an incredibly productive time mapping out and sampling impactite ejecta lobes. Last year we thought ourselves lucky for finding about 30 pieces of impactite during our whole field campaign here. These guys blew that away before lunch the first day of their sampling. We have samples representing the full range of impactite sizes, and have identified and sampled multiple lobes extending down the flanks of the crater. This provides us a great opportunity to do some statistical analysis on the size distribution of the melt fragments in different lobes to look at differences in energy, and extrapolate to the angle and direction the meteorite came from. It’s also a great sample set to look at the chemistry of the melt rocks and see if there are any differences between the different lobes.

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Sarah and Monturaqui Impact Crater

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Sarah sampling for magnetic material on our traverse

Last, but not least, we were joined by one more team member on Sunday, David Peate from the University of Iowa. I was very happy because David’s my husband and it was lovely to see him again since I’ve been here in Chile for the last 6 weeks doing fieldwork. After more than 30 hours of travelling from snowy Iowa to warm and sunny San Pedro, David is vey happy to be here too and we’re all looking forward to another day at what we’ve come to think of fondly as our impact crater.

Ciao,
Ingrid

Monturaqui Impact Crater (Monday-Wednesday Dec. 8-10)

For the last three days we’ve been on the trail of impactite. We’re a team with a mission – and that mission is to sample as much of this melt rock as possible. We have big plans for these little rocks – statistical analysis of size distribution, geochemical analysis of compositional variation, geochronological analysis of impact crater age. The only problem is that they’re really quite difficult to find, especially when you’re walking around just looking at the ground. The best way to sample (a technique perfected by Nathalie) is to assume the following position: kneel on the ground, preferably facing uphill, and bend over until you are between 18 inches of the ground and your nose hits the dirt. Then, and only then, can you truly observe the abundance of impactite littering the ground. These guys range in size from a few millimeters to almost 10 centimeters – of course the bigger ones are so much easier to find that most of them have already been picked up by previous expeditions and meteorite hunters. We’re quite lucky that Monturaqui is separated from civilization by 2 and one-half hours of some of the bumpiest roads (and I do use the term ‘road’ loosely here) I have been on. Some parts are more accurately described as driving over slightly less large rocks between the boulders. Only truly inspired explorers make it out this far. Because of that, we actually have quite an abundance of impactite, especially the smaller pieces. We’ve been working hard these last few days, and have mapped out and sampled multiple lobes of ejecta. Nathalie has been practicing her zen and thinking like the crater – or would it be the meteorite? – to aid in her mapping of the ejecta. According to Carlos, she also is able to call up a gentle breeze when it gets too hot. Maybe we’ve been getting a little too much sun lately.

I have been quite impressed with Nath’s zen mapping skills, and in an effort to expand my horizons a little, I decided to forgo my usual field approach of rock smashing and give the zen a try. I can’t say I really felt it working for me. David and Sarah and I were walking around the edge of the crater, continuing a survey of a melt lobe the rest of the group had started a few days ago. We found a few impactites, nothing really impressive, and then we hit a patch with nothing. There’s not much more depressing than crawling on your knees over very sharp and pointy rocks, looking for tiny blobs of brown melt rock, for what feels like miles, only to find…nothing. Lots of sharp and pointy rocks, though, and it felt like my knees found every single one of them. Not being the type of people to just give up, we soldiered on, continuing on our quest for impactite, but inside I was having doubts. What if it was restricted to a small area? What if Nathalie and the rest had already found every single piece left on the crater? How could I come back empty-handed? Then, just when it looked over for us, I decided we should try one more traverse along a fairly uninspiring patch of granite scree. We walked, and looked, and bent over, and nothing. We were three well-educated individuals devoting all of our attention to finding some little pieces of brown, bumpy, lumpy, glassy rock. Still nothing. But there – hiding under a larger rock, a brown blob. A melt rock! I had found one, but only a small one. We continued on, hopeful. There was nothing for another few meters (and when you’re crawling, a few meters seems like forever), until suddenly, they all seemed to appear at once – the ground was absolutely covered with impactite. I would see one and reach to grab it but get distracted by a bigger/better/closer piece on the way. Sarah was an impactite picking pro – she had easily twice as much as David and I put together by the time it was time to leave. We have (unofficially) named our find the Byram-Peate-Peate lobe (BP-squared for short). We’ll see how that goes over in the peer-reviewed science articles.

Mont_Hawkeye

Our success at finding the BP-squared lobe is just a small part of what has been a highly successful field project. Nathalie, Edmond and Carlos have invested a large amount of time and effort to finding, mapping and sampling impactite lobes that haven’t been mentioned in the literature before. We’ve defined new boundaries for these deposits and we have high hopes that the exciting science discoveries will continue with the lab work we have to do on this sample material in the coming year. We finished off a spectacular field day with a Team Iowa photo – Sarah, David and I on the rim of Monturaqui with a University of Iowa flag for scale. Did I hear a ‘Go Hawkeyes!’ somewhere in the breeze?

Last Day at Monturaqui

Thursday and Friday, Dec. 11 and 12

Thurday turned out to be my last day at Monturaqui. Ingrid and I started on the south side of the crater and followed a gully around the outer slopes of the crater for most of the day. Our hope was that we might find some iron shale that had washed away from the flanks of the crater. We followed the gully as long as we continued to find melt rock, picking that up while searching for rusty colored shaley bits of rock. Meanwhile the other crew of Nathalie, Edmond, and Carlos combed through one of the small ejecta lobes, also searching for anything that fit the iron shale description or that was magnetic enough to make the compass needle spin. It seemed especially hot out, since Ingrid and I were blocked from the breeze down in the gully. We were pretty exhausted and ready for a shower and a nap when we finally went back to the cars, but at least we had some more impactite to show for our efforts. Our fieldwork at Monturaqui is finished for this year, but we have more samples than I think anyone expected, so there is plenty of lab work ahead.

Sarah_1
Sarah scouring the gully for impactite

Friday the Iowa crew decided to check out a few different sites. I have been working on samples from Laguna Lejia and David has been working on samples from Cerro Overo, and since we are both here now Ingrid thought it would be a good idea for us to actually see these incredible places! We took the short (but slightly more difficult) road to get to Lejia first. The route included a very sketchy road through a very steep ravine, a significant climb in elevation, lots of birds and wildlife, and unbelievable views of Lascar Volcano and others. When we finally got to the laguna it was briskly cold outside and super windy, but there was enough sun to stay warm. We looked at several outcrops of the carbonate rocks and sediments from the paleolake terraces. Ingrid even showed me exactly where some of my samples came from. We also took time to snap a few photos of the lake and the reflections of the volcanoes in the background.

Next we drove up a little higher to check out Cerro Overo. This is an incredible maar volcano crater located not far from Chiliques, another volcano that sticks out of the Altiplano behind the crater. Just inside the rim of the crater there is a large basalt outcrop that blocks the wind nicely. We sat there in the sun for our lunch break, enjoying the view from just under 15,000 feet. After lunch I went to check out another outcrop, David grabbed a few more samples, and we all took several photos before heading out. We decided to take the longer road home, to see some new scenery. We got much closer to Lascar on the way out, and David and Ingrid picked up samples from a couple different volcanic flows to use for teaching purposes. It was both a productive and beautiful way to cap off our work here, and future University of Iowa Geoscience majors will have a lot of Chilean rocks to study.

Sad to Leave

Sunday Dec. 14

This year’s fieldwork in Chile is officially complete! While I’m sad to leave behind such a beautiful and geologically unique place, I’ll go back to Iowa tomorrow having learned a lot during two weeks of this very successful field season. The work I participated in is unlike any fieldwork I’ve done before, so it has been excellent practice and experience for me. Working with new scientists and professors has allowed me to observe their methods, and that has helped me learn a lot about working in a team, and the importance of being organized and having a plan, as well as being flexible with that plan.

Prior to arriving in Chile I read several papers about the work that had been done at the site. One of the more interesting things about this experience has been the chance to put what I read into context and actually see the things these geologists were talking about. I can see how one geologist might interpret samples from Monturaqui differently from another. It makes the fieldwork and the lab work more exciting to know we might have evidence to support ideas that have not been discussed yet in the literature, about this place that has been studied so little.

On a non-geological note, I learned that I can still speak a little Spanish, which will be useful if I come back to South America to do fieldwork in the future, and I hope to! Talking to Juan about the sites in Bolivia has made me want to visit that country as well, and there is so much to see and study in Chile that I’m already looking forward to new geological adventures that will lead me back here.