Final Log Entry — Land, Ho!
Finally, after over a month at sea, we've arrived back in port, safe and sound. Everyone's excited to see dry land again, though it's a little bittersweet as we say goodbye to the new friends we've made during our journey.
Our voyage may be over, but the science is just starting. We're returning home with many GB of data to finish processing and pouring over... (and several more articles of clothing than we left with, thanks to our multitalented knitting watchstanders). As is often the case in science, the data hold both answers AND new questions, and a few of us are already scheming up ideas for future projects here. Perhaps some of us will head back to the Bight some day. Until then, it's been a great trip, with interesting science and fun new friends. Many thanks to the crew of the R/V Langseth for making us feel at home (not to mention the safe passage), the marine techs for keeping everything running (even when it meant being woken up at 2am to fight off mysterious network problems), and the rest of the science party for a job well done!
Last Day of Science — A Few Things This Cruise Has Taught Us... Besides All the Science
We’ll be back on dry land in less than a day, and as most of us have been dreaming about bonfire nights, cold beer, sushi feast or just a non-moving bed for a week now, it is also appropriate to look back at this amazing experience.
First and foremost: “Boring science is good science”. Unless we are in a storm our 4 hr x 2 watch is pretty dull. Meaning that besides keeping a 30 minute log, keeping track of passing waypoints and if we are super lucky a XBT probe launch, there’s not much else to do. That’s a whole lot of time to kill. You can either listen to music and dance/sing, turn your hair grey while trying to contact the rest of the world, snooze, find the meaning of life with a Magic 8-Ball or be productive. I’ve, for example, finished 3 books, knitted an Icelandic sweater, lopapeysa, and a hat. Next time I’ll bring a huge bag of wool with me as one sweater took me 8 days to make and apparently the interest in buying a sweater among the ship’s crew is high. There’s also a growing fighter fleet for a galactic origami war and a small petting zoo with origami spider and parrots. And Yoda...
Bern gets a knitting lesson...
By far the most challenging and dangerous daily activity you can do on a boat is taking a shower. One rule: NEVER let go of the handle/rail on the bathroom wall or any other fixed feature for that matter. If you break the rule you’ll dance, slide, slip and fall. But if you’re into extreme sports you can try to wash your hair using two hands and time how long you can stay up on soapy feet in a pitch&roll(er)coaster. Another dangerous element some might encounter is a wet shower curtain that can wrap you up in seconds. It is also important to dry your feet before you step out of the bathroom as ignoring that rule will lead to you falling out of the bathroom, slamming the door, doing a split and hitting the plywood bunk or a closet door. And if that wasn’t enough, there’s another way to get into trouble, as pointed out on the first day: taking a hot shower and then leaving the bathroom door open can set off the fire alarm, meaning everybody has to go to their muster station and the fire brigade will go off to investigate... a lot of angry glares when the source of ‘fire’ is identified.
Most important thing: food! The #1 conversation topic at 6.20 AM, 4 PM, 6 PM, 9 PM and midnight. And the food here is... delicious. Hervin and Joon are doing a good job, considering the fact that you can’t go grocery shopping every day and they have 36 people to feed for a month or longer. Trying to reach a consensus in the topic of ‘best meal of the day’ can lead to pretty heated conversations among the watch standers. My watch from 4-8 with Johannes and Irene is a big fan of breakfast, because let’s be honest, who has the time to make eggs, pancakes, bacon and everything else you might crave for your first meal on an ordinary weekday on land?! Some like lunch - burgers, tacos, fries and other mouth-watering (fast) food... some have their alarms set for 1700 aka dinner or ‘meat vs. fish’. Yes, it is like picking your favourite child - you know you love one more than others but you don’t want to admit it. One thing's for sure: everybody loves ice cream. I overheard someone declare “If we run out of ice cream we’ll head back to port!” a few weeks ago. Apparently in Australia no vessel leaves port without enough ice cream for the whole trip. We ran out of ice cream a week ago. Oh the agony! Freezing cups of yogurt, eating milk soaked Oreos or a lot of peanut butter and jelly are some of the ways to cope with this tragedy. You’ll really start appreciating little things out on the ocean.
Last but not least: living at sea is not for everyone. Before coming on the boat I was mentally prepared to face constant motion, small spaces and living with a group of strangers far from land for a month. 31 days later and I am still alive! It has not been easy though... nor as hard as I imagined it to be in the first place. Probably because of the awesome company - people to goof around and find stuff to laugh about in the stormiest hours, sleepiest moments and grumpiest moods. It might also be due to the fact that I didn’t get seasick... but I might have gotten a sea-bug. I am definitely coming back on a (research) boat someday, the sooner the better! But when it comes to working at sea, in this stunning but raw and hostile environment, I have huge respect towards R/V Langseth crew and everybody else who keep the ship running 24/7 in every possible weather for years. Thank you. Only pirates can do that. Arrr!
Maria is an undergraduate geography student in University of Tartu. She spent a year in Iceland as an exchange student studying earth science in University of Iceland. She have a thing for maps, geophysics, geomorphology, volcanoes and the ocean.
Day 29 — Minding the Gap(s)
We're mostly finished with our survey! We reached the southern-most extent of our study are and have been spending the last couple of days filling in little holes and gaps in our data. Because the ship's multibeam system can only "see" a small strip of the seafloor at any one time, occasionally the data from two adjacent lines don't quite overlap, especially in very shallow areas or in rough weather when we're pitching a lot. We've also had a couple gaps when the systems were down for one reason or another. As we head north, we've been driving over the biggest and most important holes in the bathymetry data. We've also been collecting some extra magnetics and gravity data, which will give us denser coverage in our most important area.
Now all the gaps in the main study area are filled, and we're heading north towards Iceland, with plans to stop by an area on the way where there were a bunch of earthquakes recently. We want to check and see whether or not they might have been related to a volcanic eruption. If so, we should be able to see the highly reflective surface of recent lava flows in the backscatter data.
In the meantime, the figure below gives you an idea of the size of our main survey area (colored areas). By the time we finish, we'll have mapped an area about the size of Iceland!
Days 24-25 — Sailing into the Bight
The past few days have been fascinating as we come into the Bight Fracture Zone, a key area of interest for our study. Fracture zones form at places along the mid-ocean ridge where there are offsets in the ridge axis. (See diagram to the right, lifted from Wikipedia). An offset in the spreading center creates a strike-slip fault, called the transform fault, where the lithospheric plates on either side are (very slowly...) moving in opposite directions. Fracture zones extend out to the sides of these transform faults, sometimes for thousands of miles. While not faults themselves (both plate segments are now moving in the same direction), fracture zones are essentially like scars, representing the evidence of past transform fault activity.
The Bight is particularly interesting to us because it seems to be the furthest tip of the ridge reorganization process we're studying. It thus gives us a look at the very early stages of how this process works. The Bight transform fault is the first transform fault along the Mid-Atlantic Ridge that this reorganization process has not yet eliminated (see Science Overview for more about the reorganization). No one's ever mapped this area of the seafloor, so we weren't sure quite what to expect going into it, but it's been everything we hoped for and then some! We're still pouring over the data and have some more surveying to do to get the full picture, but looks to be developing into a fascinating story.
For more on plate tectonics and mid-ocean ridges (divergent boundaries): http://pubs.usgs.gov/gip/dynamic/understanding.html
Today's post comes from Irene, an undergraduate student from Madrid who was on exchange at the University of Iceland taking geology and geophysics courses. Irene was hit hard by seasickness, and has written about her experiences overcoming it and adjusting to life on board. We're happy to have her fully recovered and diving into the science and social life again!
Day 24 — Science isn't always smooth sailing...
post by Irene Taboada
First-time experiences are not the same for everyone and when it comes to living in a ship on the sea, people's bodies adjust in different ways. Some may get through it quickly and some may get seasick as I did.
The first day (Monday) when the research vessel was still in the harbor, the motion was quite similar of being on land but it smelled different -it was not bad- just something that I was not used to.
The following morning (Tuesday) we sailed from Reykjavík and the journey seemed to be comfortable for a few hours. I was nervous about getting seasick and started taking two pills against seasickness every six hours, and was also wearing a patch and two wristbands. I started feeling dizzy and got a headache the first night during my watch. I thought it would be better the next day but it got worse. The following morning I could feel how both my body and mind were trying to fight against the motion of the ship. I kept on with the medication for two days more and I was eating only crackers and apples.
I decided to stop using any type of medication against the seasickness by the end of the week, but we happened to be in the middle of a storm that Friday night. I was feeling awful, I did not have any energy left and the idea of eating, drinking and even the smell was completely disgusting for me. I did not understand what was happening because I'd never felt that way before and I started to be scared and afraid of what could happen later. After we passed the storm I did not experience any progress. I was feeling even worse. Eventually, I started forcing myself to eat and drink in order to keep me hydrated. Step by step, and with the help of pills for the nausea, I finally started feeling good after two weeks and I came back to the routine.
That was one of the hardest experiences of my life because of the fear of the unknown: being in a new place with new people, away from your family and friends and everything that I was used to. At first I wanted to leave, but I found that all these new people became like my family and as soon as I started feeling better I got to know and trust them and we now share memories that will last a long time.
I do not regret coming here and have met new and really kind people and I am glad I had the opportunity to share my life with them. Being surrounded by friends was the most helpful way to overcome the situation, and I am grateful for the help I have received during my seasickness. This was not only an academic but a personal experience that made me stronger. Before coming here I encourage myself to not be afraid about what would happen during one month on a ship in the middle of the ocean and I did not let my fears stop me from doing something that I wanted to do. Now I encourage myself to keep an eye for the next adventure.
Irene Taboada is a geology student at Complutense University of Madrid, and was at the University of Iceland on exchange. She is on her last year working on her bachelor's thesis. She's specializing in seismology, with an interest in paleontology and meteorology.
Day 23 — Happy 50th, Plate Tectonics!
50 years ago this week, Nature published a very influential study in Earth science. In that paper, geologists Frederick Vine and Drummond Matthews were the first to link alternating magnetic stripes on the seafloor with the theory of continental drift, recognizing that the seafloor was spreading and pushing continents apart. Correlating the magnetic stripes with seafloor spreading was a key step toward the development of the theory of plate tectonics. Nature has an interesting article out this week on the history behind the theory, recognizing not only the Vine and Matthews magnetics study, but also other key influential players and studies that culminated in the final theory that eventually gained consensus. It's a nice example of how individual studies are just small pieces of the bigger picture, and successful scientific theories are the ones that explain the sum of all these smaller parts.
Our study, too, is yet another small piece of a much bigger puzzle, as we try to understand the details of some of these processes. Half a century later, the theory of plate tectonics is alive and well, and still holds many questions for us... questions that bring us out all the way out onto a ship in the middle of the North Atlantic in search of clues.
The age of ocean rocks increases (red to purple, 0-280 million years) with distance from ridges, where crust is formed, revealing the spread of the sea floor. (Image credit: Elliot Lim/CIRES/NOAA/Natl Geophys. Data Cent.)
post by Chris Horvath
Contrary to popular discussion overhead in the galley, there is a point to all this drifting and isolation. We are here to affirm assumptions from lands far away. To stand firmly on ground never before tread upon — so to speak. To discover the secrets of a land not yet explored. At least so I'm inclined to believe.
My job is fairly straightforward. I stand watch over the scientific equipment collecting various types of data, by monitoring the computers designed to record the data in real time and help troubleshoot and launch the equipment required to retrieve said data. I suppose a brief walk-thru is in order to fully understand what we are collecting and how it can be considered accurate and true.
We are here to map, analyze, and determine the differences in how the earth's plates are interacting south of Iceland along the Mid-Atlantic Ridge, in an area known as the Reykjanes Ridge. To quote the Project Summary per Hey, Ramirez, Höskuldsson:
"The project is month-long marine geophysical expedition to collect the multibeam, magnetic & gravity data that would provide a definitive test between the fundamentally different thermal & tectonic hypotheses for exactly how the Iceland plume caused the reorganization of the Mid-Atlantic Ridge south of Iceland."
In layman's terms: how have thermal and tectonic forces interacted over time to form the Reykjanes Ridge, and is there a pattern to this interaction by which we can better understand how Iceland has formed and will continue to form in the future.
In the short term, this can have significant impact on Iceland's economy. You see, there is an invisible barrier around every country bordering a body of water touched by another country. It is called the Exclusive Economic Zone (EEZ), and limits all commercial offshore activity within the zone to the country of ownership. This is pretty darn important when you consider that Iceland is in the middle of the North Atlantic, about the size of Indiana, and only about 40% of it is reasonably inhabitable. It's so important that the country's governing body for all things related to geology, geophysics, and plate tectonics sent a representative (his name is Sigvaldi) on the Langseth to develop a case for Iceland to expand its EEZ to include the Reykjanes Ridge all the way southwest to our survey location and beyond. This would be a huge development as Norway, Scotland, and Denmark all are looking to exploit these waters for their potential as sites with deposits of oil and heavy metals, fishing, shipping routes between Europe and Greenland/Canada/US, strategic military advantages, and (to a lesser degree) whaling.
The first type of data we collect is magnetic, and we do this by deploying a tethered Geometrics G-882 Cesium Marine Magnetomoter. "Maggie", as she is affectionately called, resembles a stinger missile with a bonnet on her noggin. She is launched from the Main Deck, Starboard Aft of the Stern, by at least two technicians: One to apply the Van Sumeren technique of "gently" heaving her overboard; the other to man the hydraulic winch, which spools out the designated 200 m of powered cable. Due to our optimal surveying speed over ground of 10.5 kts, she rides quite high in the water as she measures the magnetics being emitted into the water column. This is done by recording the changes in pressure that occur in a Cesium vapor vacuum-sealed cylinder within Maggie. Typically she is reading the magnetics from the earth's crust some 1000-3000 m (3000-9000 ft) below where she rides in the water column.
The Earth is magnetically polarized, like a battery, with a positive and a negative point existing typically near the North and South poles. Over time, the magnetic field surrounding the Earth can swap polarity, and has done so since its inception with little fanfare. Newly created crust will take on the polarity characteristics relative to its proximity with the poles. Over time, these values can diminish. This constantly updated/recorded reading from Maggie is strongest in areas where the most recent volcanism has occurred, such as in the deep trough located in the middle of the ridge (we call this location the spreading center axis, as pertains to the meeting of the Eurasian and American plates). Abnormally shifted values outside of the axis might help us determine that there has been tectonic reorganization occurring, leading to older layers of the Earth's crust being exposed next to relatively new ones. (See also Jonathan's detailed look at some of our tools and methods for more information).
Maggie is a delight to work with when she is attached to the boat, but is temperamental with heavy seas and high winds and attempts to retrieve her must be done in the worst and most dangerous of conditions. I say attempts because after retrieving all 200 m of cable early last week when we stopped getting magnetic data, there was no Maggie. $20,000 in the drink. Luckily we had a spare onboard, but should this happen again we would be unable to record this very important data. So, when storms sweep through, we pull her out of the water.
Side note on storms, of which we have weathered three major systems. Last week there was flash flooding, baseball sized hail, and 60+ mph winds back home in Traverse City. On average, storm systems take between 3-6 days to reach us, and those that pass through the Great Lakes are almost guaranteed to head right for us after leaving North America. It's not so much the precipitation that we worry about, but the high winds. That same storm system hit us strongly a day and a half ago, resulting in sustained 50 kn winds and waves as large as 9 m (30 ft!) until early this morning. Because of the length of time of said winds, we are projected to have 4-6 m waves for the next four days — uggggh. That means everything you care about needs to be strapped down, walking down hallways is a workout, and sitting in a chair during watch can be hazardous to your health. That also means sleeplessness and seasickness rear their ugly, conjoined heads. It's best to sleep wherever you can whenever the moment takes you; be it barricaded (taco'd) in your bunk, in the movie room, or even in the main lab (though, sleeping during your shift is highly frowned upon).
The second type of data we collect is gravity. It is far less elegant and far more complicated than magnetic. In the main lab there is a Lacoste & Romberg G237 Gravimeter, which measures the strength of gravity in a given location of time and space. The data is constantly being updated/recorded and helps us determine the density of the materials that make up the layers of the crust. Combined with a extremely low frequency sonar system (called a sub-bottom profiler) and sampling, it can provide an incredibly accurate picture of the geology and geomorphology. Unfortunately, the sub-bottom profiler (our Knudsen 3.5 kHz Sonar) had to be turned off because it operates at a frequency that can cause problems with our EM122 Multibeam Sonar used for bathymetric data.
Which brings me to our third type of data, the one I was trained in at Northwestern Michigan College, and consequently the reason why I was selected to be a part of this cruise: bathymetric data. This is collected using our Kongsberg EM122 Multibeam Sonar operating around 12 kHz. The sonar has an encased piezoelectric crystal that vibrates hundreds of thousands of times per second when electricity is applied to it, sending out that energy in the form of measureable acoustic pulses. These pulses reflect off targets in the water column and return to the sonar where they are "heard," and provide us with an accurate measure of depth in a given point on Earth. As with the prior two systems, knowing our geographic location on Earth is essential to collecting accurate data; and, they are all integrated with our multiple GPS/Satellite-based positioning systems located at unobstructed points on the top of the vessel.
The more depth measurements we can collect with each ping of the multibeam the more defined the picture we can see of the shape of Earth's crust. This is by far the most interesting data to stand watch over, as it is projected on the monitors in a three-dimensional (and very busy) display. Not only are we keeping an eye on the 3-D Terrain Modeler, but also the 2-D Geographical (seafloor map), the black and white 2-D Seabed Imagery, the convoluted Water Column display (which provides us with backscatter data - used to see thermal activity in real time), and various readouts of motion and sound velocity which help determine the quality of data being collected. Sound velocity (or the speed of sound in water in this context) is extremely important as it allows for us to calibrate the sound pulses on the fly so that they return to us in a straight line rather than with a bend (which would give the illusion that the distance to the bottom is longer/shorter and in a different location than it really is).
We measure sound velocity on this cruise by launching XBTs(Expendable Bathythermograph) manufactured by Lockheed Martin Sippican. An XBT is a bullet-shaped lead weight attached to two thin copper wires within a plastic mortar tube that is released from the streamer deck. Those wires are linked to a powered cable that connects to the lab, where measurements of temperature, salinity, pressure, and depth are recorded. Typically, we use the T-5 model which is rated to 2500 m. It falls quite rapidly and within five minutes has reached the end of its wires, whereupon the wires are severed and the probe lost to the deep. Two important things to remember when launching an XBT: First, don't let the wires touch any metal or it will short out (everything is metal on a boat); and second, don't fall overboard!
Thank you for bearing with me in this blog as I delved into the depths — so to speak — of what I do while working aboard the R/V Langseth.
Chris is a student at Northwestern Michigan College, where he's majoring in fresh water studies. He's joined our crew courtesy of the MATE intern program. His experience with bathymetric studies make him a welcome asset to our team!