So, since I’ve been more or less slacking on the whole blog posting thing the last couple days I’m going to do a quick recap. Two days ago we sampled some rocks…it was pretty standard. Nothing that y’all really need to hear about. Still pumped on pumice…yay Tephra Team!
Yesterday was a wee bit more exciting! The Tephra Team split up into two groups. Lydia, Tyler, Olivia, and I went to look at some really cool geothermal activity just outside the Rotorua area at the Waiotapu Geothermal Thermal Wonderland while Nicole and Elizabeth went to Hobbiton! The aforementioned group also, after observing a bunch of beautiful and smelly pools of water, went rafting on the Kaituna River! This river route has the highest commercially rafted waterfall at 7m (23ft) and some really amazing guides from Rotorua Rafting Company to lead you through the whole process. We only almost died like 3 times! Kidding. Or not. Go on the river and experience yourself. I would write more about this whole thing, but I’m tired and y’all probably like pictures more anyways, so here it is! Enjoy! After this whole trip is done with I’ll also have a video of the whole trip and you can see firsthand what we experienced.
Since I also know that everyone reading this thing is just as much of LOTR (Lord of the Rings) nerds as we are and are itching to know what Hobbiton is like, Nicole will post on that in the near future!
Tongariro crossing is tomorrow, so stay tuned for some pics of cool volcanoes and sweet views of the North Island!
Today is the day that we leave the coast behind us and head south towards Rotorua. We have more or less everything we need from up by the Bay of Plenty and are moving south to sample Te Rere, Kaharoa, and Rotorua eruptions. The sun is shining, spirits are high, and we are ready to vigorously sample more pumice after taking a day off to observe the wonders of Whakaari.
Our first stop was actually none of the aforementioned eruptions and we stopped to sample some of the younger Mangaone eruption. This went relatively smoothly, and we headed further south to try to continue on our sampling journey. Our stop was in some logging territory that had been recently clearcut, however some of the eruption units were supposed to be easily visible. We drove up logging road, found where we were supposed to sample, and began to empty out of our vehicles. It was at this point a small pickup truck came ripping up the road and skidded to a halt just in front of us. A very large and aggressive lady stepped out and began ‘politely’ asking us to leave the premises since we did not have a permit to be there. (Logging land in New Zealand is privately owned by individual logging companies and you need a special permit to be there). We promptly obliged, went back down the mountain, and continued on our way. On our way out we noticed that there was a sign at the base of the road that notified us that this was private property and there was to be no trespassing. The only problem with this sign was that it was behind a significant amount of vegetation and not really visible. Oops.
We then moved on to sample the Te Rere eruption along the coast of Lake Rotoiti. This went off without any complications or yelling, so we considered it a success for the day. Lunch was pretty standard for the day, consisting of sandwiches, fruit, granola bars, and some corn chips. New Zealand has fantastic corn chips.
Our final stop for the day was the Rotorua Pumice Quarry. Here they mine pumice for use in making concrete, and let me tell you there is A LOT of pumice. Like…A LOT. Here we were sampling the Rotorua eruption (go figure) and had a beautiful 15m exposure of this eruption. The reason there is so much pumice here, is that we were quite proximal to the vent of the eruption. The closer you are to the eruption, the more eruptive material you will find. This relationship is actually what field geologists use sometimes to help locate vents that may be hidden in the subsurface. After shooting some informative educational videos on physical volcanology here, we were on our way and it was time to make base camp for the evening! The new home for the Tephra Team the next few days is at the Rotorua Holiday Park, and it is quite nice. We have a few cabins to house the squad, complete with small kitchens, bathrooms, and some coin operated laundry. Everyone has come to the consensus that this field work is definitely not exactly near the top of ‘most difficult’ field campaigns in our academic careers. However, none of us are complaining…except for the rotten egg smell in Rotorua. All of the hydrothermal activity in the area makes the air smell of rotten eggs…everywhere.
Goal for today, don’t get yelled at for being where we aren’t supposed to. Also, on a more scientific note…our goal is to sample some of the Taupo Volcanic Center, more specifically the Taupo, Oruanui, and Omega Dacite. Spoiler alert: we achieved one of these goals.
Our first stop was at a beautiful road cut that exhibited both the Oruanui eruption, Hinuera formation, and the Taupo eruption. Our only sample of interest here was the Oruanui and to bag some of the beautiful, large, pumice samples found within the ash flow unit. This unit is 25 thousand years old and erupted 500 cubic kilometers of ‘stuff’. For scale, the Mount St. Helens Eruption was 1 cubic kilometer. That’s a lot of stuff. On top of the Oruanui eruption was the Hinuera formation, which is ash fall derived from the Oruanui. Ash flow units (also called ignimbrites) are derived from erupted ash moving laterally across the ground, whereas ash fall (also called tephra) is the ash that falls from the sky.
After bagging a few bags of soccer ball sized pumice, we moved on to a more ambiguous unit. We believe it is either part of the Taupo or Oruanui eruption, however it has been labeled UNK (for unknown) by the Tephra Team. We did a lot of detailed stratigraphic mapping here, bagged one sample bag, and moved on to Lake Taupo for lunch. Stratigraphic mapping is where you make a ‘map’ of the vertical extent of volcanic units as they exist in the subsurface. This helps you relate the time of eruptions to one another and gives you a frame of reference for where you may be in the volcanic zone’s history (i.e. if you have units A,B,C,D with A being the youngest and D being the oldest, when you find yourself in unit B you know A must be above you and C,D below you).
Lake Taupo turned out to be a beautiful place for lunch, however a toxic algal bloom turned out to be present in the lake and prohibited any swimming.
Post lunch it was time to sample the Omega dacite, do some more stratigraphic mapping, and call it a day. It took a little bit of digging through new soil to find the correct unit that we were in (stratigraphic mapping proved to be a good frame of reference here!) but we ended up getting what we came for.
Upon returning to base camp the team organized samples, did some laundry, ate another good meal, and coordinated the next day’s sampling plan of attack.
All in all, successful and very enjoyable last couple days in the heart of the Taupo Volcanic Zone!
Tomorrow we can take our foot off the gas with respect to sampling and have a more relaxed day. We’re actually ahead of schedule for sampling at this point in the trip.
Okay. Ooooooohhhkay. I’m going to try and walk you guys through today without sounding too much like a crazy person. Today the Tephra Team went to White Island or as it is known to the Maori: Whakaari. It is an island roughly 45km off the coast of New Zealand out in the Bay of Plenty. It is also New Zealand’s most active volcano, and has ongoing fumarole activity present throughout the island. Fumaroles are surface expressions of an active volcanic system beneath the surface of the earth and are usually observed in the form of bubbling mud pots, boiling liquid (some water-acid concoction usually of extremely of low pH), and gas emissions. It also erupts quite frequently in the form of explosive andesite eruptions and has killed miners who lived there in the early 1900s.
A quick crash course on volcanic gases:
Gases associated with volcanoes can be a multitude of things, but are usually water vapor (H2O), carbon dioxide (CO2), hydrogen sulfide (H2S), and sulfur dioxide (SO2). The source of these gasses can be either from the magma or incorporated from the surrounding rock as the magma propagates through the earth’s crust. Water and carbon dioxide are pretty harmless for the most part, unless at extremely high temperatures (which can happen frequently in fumaroles when the magma is > 700 degrees Celsius), but hydrogen sulfide can be pretty nasty. It is quite irritating to the throat and eyes, causing a burning sensation in both, and in a liquid state can form sulfuric acid (this is an oversimplification of some chemical reactions, but moral of the story, the stuff is bad) that will dissolve just about anything you’re wearing or carrying…including you if you sit in it long enough.
Now that we’ve established that there can be some nasties around active volcanoes on top of the whole “they go boom” thing, we will continue on our journey. The day started out quite rainy and was looking pretty choppy out on the water. Good thing we all brought our boots inside overnight this time so they remained dry. Anyway, we continued on to the place that gave the tours, confirmed that we knew the risks of traveling to an active volcano, boarded the boat, and were off. Turns out our observation of the water being quite choppy was incredibly accurate. We would later learn that they don’t usually go out on the water when it is this rough, but because some of the people on the tour were only in town for one day the company didn’t want to have them miss out on the experience, and so out we went!
Once we got out into the Bay of Plenty we were able to feel the full force of the waves on the catamaran style boat. Catamarans feel waves more than more traditional styles of vessels and this exacerbated every single up and down. Now, some of us on the trip are not exactly fond of this type of motion repeated over and over again for two hours. Call it motion sickness, call it sea sickness, call it whatever you want, but it all usually ends up with you tasting your breakfast twice. Fortunately, we only had a couple of casualties in that regard, and I was not one of them. A little advice for those of you heading out onto open water and looking to calm the nausea: focus on the horizon or island if you have one and concentrate on your breathing. The focusing on a stable landmark helps your body get its bearings. If you do these things it will not be as bad. After about two hours or bouncing around we finally made it to Whakaari! By this point the wind had died down and the sun was shining. I guess the Maori gods were just toying with us and making us earn the right to step foot on their island.
The first thing you will notice when stepping on the island is the smell. Sulfur in its native form is odorless and tasteless, but when in the form of hydrogen sulfide, it is most definitely not. The smell of rotten eggs filled our nostrils, we were given gas masks and hard hats, hopped on shore, and were off! Shades of various yellows, reds, browns, and greys covered the landscape and it was unlike anything I have ever seen. Honestly, it looked like we were transported to another planet. But that’s the beautiful thing about the earth: just as soon as you think you’ve seen all there is to see, it throws something at you that will make your head spin. Stopping along the way to ogle at various sulfur mineralization, volcanic bombs, landslide debris, and air fall deposits, our heads seem to be on a well lubricated swivel. Picture snapping, video taking, and science talking our way to the main event, we finally reached the center of the island: the youngest vent and remnants of the caldera lake. This is where all of the recent eruptions originated and launched literal tons of volcanic ejecta. Some of these ejecta (we call them bombs) were as big as a small car, some were as small as a softball, but they were everywhere. One would not want to be around when this thing blows its top. Even with a hard hat, these projectiles are traveling as fast as a bullet and are hundreds of degrees Celsius, so your odds of survival are not that great. If you do find yourself experiencing one of these and are in the immediate vicinity…best not to look down. Look up, look for bombs, hopefully dodge them, and get to some shelter!
Up here at the crater there were A LOT of gasses being emitted from various vents around a small water/acid lake and when the wind was jussssssst right we got a nice whiff of the sulfuric gases that subsequently burned our throats and eyes. It was then that we were thankful for our gas masks and sunglasses to block out the nasties.
Post gawking over the central vent we made our way down through some landslide deposits associated with eruptions and observed the old mining operation that was present in the early 1900s. Because of the native sulfur deposits, mining was implemented on the island for a couple decades in early the twentieth century with the aim of using it for use in fertilizer. In theory, this seemed like a simple “smash and grab” operation, however there are a few problems with mining on an active volcano, namely it is an ACTIVE volcano. They go boom occasionally. Also, because of the acidic nature of the gases, the metals used in buildings oxidize and weather extremely fast. All of the buildings have since fallen apart and the metal used looked like it had been there for ten times as long as it has actually been present. After a couple of eruptions, landslides, and deaths of dozens of workers, mining ceased to exist in the area and all that’s left are the remnants of the buildings used to process the sulfur and house the miners. Shockingly, it seems as if the wood used as structural supports holds up exponentially better than the metal in this case because it is not affected as much by the acidic clouds that frequently dominate the island.
Shortly after viewing the demise of human presence on Whakaari, we boarded the boat back to Whakatane and had some lunch. This was my first experience with a savory muffin and let me tell you…I would totally endulge again. It is very much like a quiche and quite delightful! The ride back was much smoother for a couple of reasons: we were heading in the same directions as the waves, the waves seemed to have died down, and we were giddy on volcano things. No barfing this time around!
Upon returning to shore a bunch of us hit the gift shop, I mailed a post card, and we headed to…you guessed it…BLUEBERRY CORNER! It was time to make a great day better with some fresh fruit ice cream! Rough life we lead. It’ll soon be time for some fish n’ chips and nightly science discussion.
Today I thought that, instead of writing a novel, I would provide you all with some visual evidence of what our field work is like! No pictures of ice cream, sorry. Enjoy the following scenes from the last few days!
Sorry for the gap in posts, but the following was supposed to be uploaded yesterday. Some technical difficulties prevented that, but have since been resolved! Enjoy…
Today was “typical day” studying the Taupo Volcanic Zone. By this I mean that we drove around a bunch, had a hard time finding the correct eruption units (because there are 57027562 different units and they all look very similar), eventually figured it all out, bagged a ton more pumice, and called it a day. The units of interest were the Hauparu and Maketu and these are part of the Mangaone eruptive sequence. These are slightly younger than the Rotoiti caldera forming eruption and we are sampling them to get a better look as to how these caldera forming systems behave before, during, and after eruption. The more eruptive units we sample and look at on both sides of these caldera forming eruptions, the higher resolution look we can get at how they evolve through space and time. However, in the TVZ, this is much easier said than done. It took us 4 hours of driving around (and stopping once for coffee) to even get to an outcrop that we could definitively say was Hauparu and Maketu airfall deposit. Needless to say, when we did reach this outcrop we went into full ‘smash and grab’ mode, bagging as much pumice as our sample bags would allow (see Tyler below for scale of the excavation work done by him and his hammer). After this we went and sampled some Mangaone airfall within the larger Mangaone eruptive sequence…super straightforward naming by whoever did the initial field work on this one. By this point, we didn’t have enough time to get to our third stop for the day, which requires special permits, so we’re tabling that until tomorrow. This shouldn’t really be a problem, as we were conservative with our total time estimates and made sure we wouldn’t be in a rush, even if things like this did happen.
We also stopped at Blueberry Corner…again. Faculty’s choice, not ours, but I’m not one to turn down amazing ice cream, so I indulged for a second day in a row. This time I went with boysenberry and it was equally as good as the mixed berry. Still 10/10 would recommend!
Upon returning home to base camp, the Tephra Team decided to go for a swim in the ocean to cool off from all of our ‘exhausting’ field work, and wash off all the pumice dust that was covering almost every square inch of our bodies. The water was much warmer than expected and was quite comfortable! Lydia, Tyler, and I then decided to go for a run, because as Kari put it earlier today: “This may be one of those field work trips where you actually don’t get in better shape than before you left”. For those of you don’t know me, I am not a runner. Even when I was playing soccer back in the day I was not a runner. Still, we went for a moderate 30-minute jog on the beach and it felt good to get the blood pumping a little bit. My feet and calves may have another opinion tomorrow morning, but that’s okay, we’ve got to take advantage of this amazing ocean front while we can!
Dinner for the night was marinated chicken breast, garlic potatoes, assorted vegetable salad, fried zucchini, and beer from Moa brewing company here in New Zealand.
To cap it all off, Tyler gave a little talk on what the Cooper research crew will be doing with the samples back at UC Davis once we’ve gathered them all. Once I get a little more bandwidth, I’ll be able to upload videos of things like that for y’all to see and provide a little more insight into our field work down here.
Although it got off to a slow start, it was another successful day of pumice hunting down here in the Taupo Volcanic Zone.
Now that I’m not completely jet-lagged, I can give all of you a proper blog post… or at least try. So here it goes!
Today was our first real day of field work. It started off like any normal day of field work usually does: early and getting the coffee going. Fortunately, with it being summer down in New Zealand there is plenty of daylight, so when our alarm went off at 6:30 getting out of bed wasn’t really a challenge. Could I have slept 4 more hours and fully recovered? Sure, but my excitement to actually go look at some volcanic rocks won out and getting out from under the sheets wasn’t really all that bad. Everyone else, based on their demeanor, also felt the same and we all gathered around the central cabin to eat breakfast and make our lunches. Today’s menu consisted of sandwiches, granola bars, and fruit. When doing field geology it’s best to keep your food simple and portable.
As 8:00 came around we were off to our first stop on the western edge of Ohope beach where we would discuss a little bit of the background of the northern TVZ, what makes it so unique in the world of volcanism, some basic goals of our research proposal, and to look at some tephra (air fall) deposits from some of the more recent eruptions. It was a bit of the climb to get out to the overlook where we would discuss the aforementioned topics, but it was hardly anything too rigorous. Surfers were scattered throughout the beach getting ready to catch some waves and the sun was already shining down in full force warranting a thorough coat of sunscreen. Apparently, the sun down here in New Zealand can be quite intense, therefore I’m not taking any chances. We spent a couple hours here and then went back down into town for a coffee break. As I’m sure you will soon realize, these coffee breaks are a regular thing and fuel most of our research.
After everyone got refueled on caffeine, it was time to go sample some eruption deposits, specifically the Matahina (320,000 years old) and the Rotoiti (45-50,000 years old). FINALLY. Time to do what we all came here to do. Getting to these outcrops wasn’t anything particularly rigorous, as they make up the majority of the roadside cliffs here along the Bay of Plenty, but the traffic and lack of road shoulder almost turned this into an extreme sport. Logging trucks will win a head on battle with a geologist 10 times out of 10. Nevertheless, we went to work on these hundred meter cliffs of ignimbrite and started filling our sample bags with pumice chunks that were scattered throughout the rock unit. The reason we sample the pumice and not the whole rock is, that, the pumice offers a definitive snap shot of what the magma composition was like within the magma conduit/reservoir immediately before eruption. This is because pumice is rapidly cooled magma. It cools so fast that it traps pockets of air inside of it, hence it’s vesiculated nature and ability to float. These rapidly cooled chunks of magma get trapped in pyroclastic flows during eruption events and when the flow completely cools give us the deposit we see today. One cannot be certain that the surrounding groundmass of rock is directly related to the magma composition, so we leave this on the outcrop and only take the pumice. Think of it as very crude scientific sculpting.
We stopped at 3 outcrops in total and collected 10, gallon sized bags of pumice. The pumice here is relatively crystal poor, so when doing intra-grain crystal studies we need to collect a lot of it in order to increase our chances of finding as many crystals as possible to do geochemistry on. As analytical techniques evolve to collect more accurate data in even less time, statistically valid data is now a very important thing to consider when doing geochemistry!
Post field work we stopped to get some fresh New Zealand ice cream at Blueberry Corner, and as someone who loves ice cream, I was pretty much in heaven. Made with fresh blueberries, strawberries, and raspberries, this ice cream was absolutely magnificent. 10/10 would recommend when you’re on the North Island. It was then time to go grocery shopping and stock up on food for the next few days while we’re up by the coast. Even though we like to think we can power our whole research project by coffee, we still need calories and actual food to get through the day. Dinner tonight consisted of burgers, brats, heaps of grilled vegetables, and some good kiwi beer or wine.
Time to go over our notes, samples, and plans for tomorrow. Things are off to a great start for the Tephra Team.
After 12.5 hours in the air, 3.5 hours in a car, skipping December 5th, a lot of caffeine, and a seemingly never ending battle against jetlag later…the Bay of Plenty welcomed us with open arms. This will be our base of operations for the next few days as we examine tephra and ignimbrites in the northern Taupo Volcanic Zone. We are limited to 100Mb of data per day per person while here aka enough to make this blog post and check email, so we will do the best we can to share with you our adventures! The Pacific Ocean is much warmer on this side than it is during the summer in Oregon, so wading into the water up to our knees felt extra refreshing.
I’m sure, that, as soon as all of our heads hit our respective pillows we will all have the deepest sleep we’ve had in a long time.
Tomorrow the science, and real fun, begins…but for now it’s time for Team Tephra to get some rest.