PACHIDERME
(PAcifique-CHIli-Dynamique des Eaux intermediaries)

The Deep Sea Coring Cruise of the
Marion Dufresne off the coast of Chile
February 2007
Cruise Sponsor: IMAGES Program
Students: Click here for a copy of a journal
Teachers: Click here for a link to activities related to deep sea coring
Click here for a brief pre-trip powerpoint presentation
Click here for weather in Punta Arenas
Click here for a Google Earth look at Southern Chile
| Daily Log | Question of the Day |
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Day 22 Log Hello from 54 degrees 24’ S 69 degrees 37’ W Here is a brief overview of the current weather: Air Temperature: 4.3 degrees Celsius Wind Direction: 231 degrees Wind Speed: 9 kts Air Pressure: 997.6 mb Humidity: 82% Cloud Type: stratus/nimbostratus Percent Sky Cover: 100% Water Temperature: 8.2 degrees Celsius
We took our last core last night, and as a farewell on his last cruise, the Captain attached his hat to the weight on the corer. A symbolic and joyous sight for all! On our last full day of the PACHIDERME cruise we are in a fjord near Tierra del Fuego surrounded by glaciers, and working on all the reports and final statistics for the cruise including the final numbers for our treasures from the sea. Besides 35 Calypso cores, 13 Casq cores, 5 HAPS cores, and 1 Gravity core we come to know the Southern Chilean Pacific Ocean quite intimately as we experienced the variety of her weather conditions, the energy of her waters, and the sediments on her floor. The majestic fjord region conjured up thoughts of the distant past when sights of glaciers 1000’s of meters high were the norm. We are sure the sediments from the fjords will provide the clues to this glaciated past.
The PACHIDERME Cruise was an excellent example of how international collaborations can work. It’s not often that scientists living thousands of kilometers from one another can work together on the same project. Their collaboration began with the writing of the proposal for this cruise a few years ago (or earlier), continued with collecting the cores on the Marion Dufresne, and will continue long after the cruise is over. We take for granted the power of the Internet to bring together people from all around the world, and here on the cruise these distant relationships were given the opportunity to meet face to face to work on similar scientific interests. We exist in a global community and there is no language barrier for understanding our Earth. We look forward to seeing/reading about the results of this cruise.
Thank you to Dr. Kissel, Dr. Laj, all the scientists, and the crew of the Marion Dufresne for sharing their world with 4 teachers. We will long remember all that has transpired over the past 3 weeks, and our students will be the recipients of the rewards of our experience.
Good-bye to everyone, and see you back in the States! |
Farewell to the PACHIDERME Cruise
Would you consider a career in oceanography or a subfield of oceanography? Why? Why not? How about a career in another “field” science? Why? Why not?
Click here for the PACHIDERME Cruise Route |
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Day 21 Log Hello from 53 degrees 32’ S 70 degrees 16’ W Here is a brief overview of the current weather: Air Temperature: 6.3 degrees Celsius Wind Direction: 48 degrees Wind Speed: 36 kts Air Pressure: 995.2 mb Humidity: 73% Cloud Type: nimbostratus, altostratus, cirrostratus Percent Sky Cover: 60 % Water Temperature: 9.4 degrees Celsius
We are currently close to home near Punta Arenas, but we won’t be going there since we will be coring through tomorrow. The expense of a cruise like this requires that the scientists maximize their time out at sea; otherwise it is money down the drain. We made it through the storm okay last night, but we didn’t find any coring sites like we wanted in the open ocean of the deep south (54 degrees).
Through these logs you’ve heard a lot about our experiences, whether they were science related or personal. Something we didn’t discuss was all the trials and tribulations of “doing” science at sea (or in the field). Because we are working with Mother Nature during the cruise, we need to take advantage of the good conditions (fair weather and calm seas) when they come, and because of this, the majority of our initial coring was done out in the ocean taking advantage of the calm seas. Using a weather report from Valparaiso and output from a weather model in England, the Captain assisted the Chief Scientist in deciding to core in the ocean before any potential storms were in our way. Storms can bring swell big swells, and although we can cruise in 10m waters, but it’s impossible to core with swells of that size.
The coring sites listed in the cruise proposal written a couple of years ago were general sites selected because of information from past research cruises and collaboration with those who know about this area. While out on the ocean, using the instrumentation available such as the echo sounder, the scientists were able to discard some of the old sites from the initial proposal and replace them with new sites. But searching for a new site can be a fruitless endeavor, and after a certain number of hours the search must be abandoned in order to look for sites elsewhere. This means a scientist may not get a sediment core for one of their locations, but time is of the essence in getting to the other coring sites of the cruise plan.
Then there’s the instruments, and planning for losses and downtime. We were equipped on this cruise with 5 core catchers on February 6, 2007, but over the past 3 weeks we lost 3 core catchers to the ocean. The winch can haul in a weight of 20 tons without any problems, and as the weight gets closer to 25 tons there is a potential that extreme damage could be done to the winch (the sophisticated cable system that hauls the corer back up from the ocean depths). The bolts, holding the core tube, upper end, and core catcher in place, have been calibrated to hold up to 20 tons, and after that they break, releasing the core tube, upper end, and core catcher into the ocean, and protecting the winch from damage. A situation like this arises when the sediment layers are too dense (possibly from a tephra layer), and the corer gets stuck in the sediment. The tubes can be replaced from the stock pile on board, but the core catchers are an expensive piece of equipment to replace, and once the 5 are gone, Calypso coring is done for the cruise.
It’s also amazing to think about all the minor things that are needed to run the science lab out in the sea, and if those items whether it’s a specific type of tape, lab supplies, storage bags, etc, are forgotten, the operations have to be altered to compensate for missing items. Fortunately the people on board are very experienced and know what’s needed to complete the coring operations. When you plan for work at home, it usually isn’t necessary to have 2 or more of all your supplies, but out at sea (or in the field) there are no “Home Depot’s” or “Walmart’s” or “Carrefour’s” around the corner, and so bringing extras of supplies is usually a prudent move.
The other challenge of research out at sea (or in the field) is the amount of time it takes to test your hypothesis. The proposal for this cruise was accepted 2 years ago, and it may be another 2 years after we get back before the scientists have the completed their work and draw any conclusions about their findings. As with any science problem, there is always that outside chance that the data won’t show what is hoped for, but with all the planning and research done before this cruise, it more than likely it won’t happen with data gathered here. Only time will tell….. |
Alpine Glacier near Punta Arenas
Why is it important to test your equipment before going into the field? What will you do before your field trip in May to be assured of acquiring good data?
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Day 20 Log Hello from 54 degrees 12’ S 74 degrees 14’ W Here is a brief overview of the current weather: Air Temperature: 7.6 degrees Celsius Wind Direction: 47 degrees Wind Speed: 32 kts Air Pressure: 994.9 mb Humidity: 77% Cloud Type: altostratus/stratus/nimbostratus Percent Sky Cover: 100% Water Temperature: 9.9 degrees Celsius
We are out in the open ocean near 54 degrees south and looking for another coring site before the storm hits this evening. We hope to take cover (the best we can!) in the fjord region in the area. The swells have been pretty high (3-4 m), and they are expected to get much higher when the store hits. Meanwhile the science operations continue!
This cruise has been an extra “sensory” experience in many ways. From the first day of the cruise, our senses have been stimulated with all types of sights, scents, sounds, textures, and tastes. When we left the port in Punta Arenas, we were immediately treated to the sights of the majestic fjords, a sight to behold when you’re in them as opposed to looking at them on maps. As we made our way into the open ocean, there was not too much to look at other than an occasional whale spout, a few birds (petrels, albatross), a shark and other marine life. But where the ocean was lacking in objects to see, it made it for it in the colors of the water. If you can imagine every shade of blue in a crayon or colored pencil box, and then add every shade of green or brown to the blues, you will have the variety of ocean colors we’ve seen over the past 3 weeks. It was as if the color changed every time we looked at it given the time of day or the amount of sunlight illuminating the surface. Another sight to behold while on the ocean was the mixture of clouds: stratus, altostratus, cirrus, cirrostratus, cumulus, etc, each one alone and all of them together.
The scents on a working vessel can sometimes be pleasant such as when the kitchen is preparing a meal, and sometimes it reminds of you of hard work. There’s nothing like working up an appetite and getting a whiff of fresh baked bread, a hearty stew, or a decadent dessert. On the other hand, the smell of a rotary saw on metal or the scent of diesel is enough to deter any appetite! The closest thing the scent of saw on metal reminds me of is the scent that car brakes give off when they need replacing. Now imagine that scent intensified and occurring almost every day. But ahhh, there is the pleasant scent of the sediment that’s enough to please the senses of any sedimentologist! The earthy smell from the sediments is reminiscent of being outside in an open field on a rainy day, and there’s nothing wrong with that.
Things that go “bump” in the night and during the day create some of the sounds heard around the ship. Many of the sounds we hear are somewhat random and there’s no way to trace them to their origin. But there are other sounds that are more distinct such as the winding sound of the winch reeling in one of the corers, and grinding noise of the saw cutting the PVC core liner segments into 2 halves, the sound of the ocean and the ship battling one against the other, and then there’s the clink of the silverware hitting the plates as all the hungry people on board chow down after a tough watch. Traversing through the ship are additional sounds such as that of the roar of a motor, the hiss of steam being released, and the sounds of those carrying on their tasks of cleaning the ship.
Sedimentologists rely on texture for their initial analysis of a sediment sample. Sediment grains come in different sizes, and can be recognized by feeling a sample. Anyone can feel the difference in sediment types, and in the 3 weeks of the cruise we have felt everything from sediments as smooth as butter, to sediments having the consistency of wet grainy mud. Although we may not be able to feel it, a single microscope smear slide of sediment has a plethora of microfossils and sediment particles, and so it always best to take the analysis beyond the basic touch. The ocean textures reveal the hidden energy of motion as the ship rocks and rolls with every swell or skates along as if on a sheet of ice. Fortunately for us the former hasn’t been too much of the rule during this cruise.
Tastes can take us back to the sediments if we think about the way a true sedimentologist tests for texture, but here we will focus on the tastes from the galley! The meals on board the Marion Dufresne have been a gastronomic delight with each meal being an adventure from trying to read the French menu to discerning among the robust flavors in each meal. We will not forget the array of cheeses, the baskets of fruits, the remarkable presentation of the dishes, nor the succulent flavors of the meats, fishes, and vegetables. Our meals have tantalized more senses other than that of taste; our eyes have observed the many colors, our tongues have tossed around the many textures, and our ears have heard the satisfied moans of the sated guests at each table. Compliments to the chef!
When we meet these stimuli in the future whether it’s on another cruise or it’s purely by happenstance, they will surely trigger our memory of the PACHIDERME cruise on the IPEV Marion Dufresne. |
What stimuli (scents, sounds, textures, tastes, sights) remind you of good things? Why?
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Day 19 Log Hello from 52 degrees 45’ S 73 degrees 27’ W Here is a brief overview of the current weather: Air Temperature: 9.8 degrees Celsius Wind Direction: 17 degrees Wind Speed: 35 kts Air Pressure: 1003.4 mb Humidity: 78% Cloud Type: nimbostratus Percent Sky Cover: 100% Water Temperature: 10.1 degrees Celsius
We are currently making our way south, navigating between the open ocean and the fjords. While in Bahia Beaufort we were treated to the site of a glacier. The outstanding blue ice against the gray background of the foggy day was a feast for the eyes! There have been questions about what people do on board the Marion Dufresne, and today’s log will tell you a little about the diversions available for the scientists, staff and crew. A 3 week cruise can be a long time to be working continuously without some way of rejuvenating your energy, and so the Marion Dufresne offers a few amenities to help keep the energy levels up. There is an exercise room equipped with 2 stationary bicycles, a stair master, a treadmill, a weight bench, and a ping pong table. People can be found using the equipment throughout the day depending upon when their watches fall. Also there is a badminton court that has been used as an indoor soccer field! There is a tournament going on in badminton as well as soccer. So far the scientists are leading in soccer and are ready to take on the navigation crew. The badminton tournament has been going on since the beginning of the cruise, and it progresses by elimination. There are about 3 more rounds to go before the champion is crowned! All of you athletes out there need to keep in mind that it’s more challenging to play these sports at sea since you have the added advantage of playing on a stable platform when you plan on land! Also there are less active ways to spend time such as socializing in the lounge, playing darts, dominoes, Scrabble, Monopoly (French version!), cards, and other games. People can also be found reading books from their personal library or from the extensive library (almost all the books are in French), or watching a movie from the extensive movie collection. Doing laundry, although it’s not a fun diversion, it is necessary given the messy nature of coring. Shopping in the ship store for ship memorabilia is another way of spending time as is catching up on emails, and taking, downloading and sharing pictures. Sometimes there are even a few that are up to some antics that keep a smile on everyone’s face! Time has been passing by quickly with all there is available to do on board the Marion Dufresne along with working on the science objectives. |
Badminton
"Basketball" anyone?
What do you think you would do to consume your free time while on board a ship for 3 weeks?
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Day 18 Log Hello from 50 degrees 28’ S 76 degrees 8’ W Here is a brief overview of the current weather: Air Temperature: 10.4 degrees Celsius Wind Direction: 322 degrees Wind Speed: 13 kts Air Pressure: 998.6 mb Humidity: 90% Cloud Type: nimbostratus Percent Sky Cover: 100% Water Temperature: 11.8 degrees Celsius
We made our way through Canal Messier and are back in the open ocean in the midst of a storm that’s creating 3-4 meter swells. Of course the science continues! You’ve only met one of the scientists thus far, and so I’m going to use this log to introduce you to a few more Principal Investigators on this cruise. Dr. Ulysses Ninnemann is one of the leading scientists on board the Marion Dufresne who comes from the University of Bergen located in Norway. He was born in the USA and attended Rice University in Texas as an undergraduate studying Aerospace Engineering. After taking a geology class, he changed his major to Geology. During his undergraduate studies he enjoyed his paleo oceanography course the most. That enjoyment led him to Scripps Institute in California where he completed his doctoral studies in Earth Sciences and Oceanography. Dr. Ninnemann’s research at Scripps focused on ocean circulation around Antarctica and how this circulation affects global climate. After completing his doctoral work he went to Columbia University’s Lamont Doherty Earth Observatory in New York as a post doc working with the Ocean Drilling Program. After completing his post doc, he accepted a position at the University of Bergen. Dr. Ninnemann is on the PACHIDERME cruise to study the association of the intermediate water in Pacific Ocean to global climate, and he is doing this by analyzing the chemistry of the marine organisms that have settled in the deep ocean during the late Quaternary Period. He is asking questions such as whether or not the changes in the climate we’ve seen in the recent past are similar or different to changes in the distant past, and why are these climate changes occurring. To answer his research questions he studies a type of zooplankton called benthic foraminifera (foram for a short name). These tiny animals have a shell made of calcium carbonate and live on the bottom of the ocean. Once they die, their shell remains in the sediments and carries some information about the water temperature and salinity at which they lived. He mentioned that useful information is obtained from both the carbon and oxygen atoms that make up the carbonate contained in the shell. Once he has recovered the foram from the sediment in his laboratory in Norway, he uses an instrumental technique called mass spectrometry to determine how much carbon 12 and 13 and oxygen 16 and 18 are contained the shell. The results obtained can tell him whether the time when the foram was alive corresponded to a rainy period and the whether the temperature was cool or warm. However, all this information needs to be validated or used in conjunction with other results to be able to have a rigorous interpretation of the climatic conditions at that time. Dr. Franck Lamy is currently at the Alfred Wegener Insitute for Polar and Marine Research, Bremerhaven, Germany. He is a geologist who obtained a German “diploma” (equivalent to master degree) in Geology and Paleontology at the University of Münster in Germany. For his diploma thesis he spent about 7 month for fieldwork in Mexico where he did geological mapping and sampling for sedimentological work on carbonate rocks (Mesozoic hard rocks) in the Sierra Madre Oriental, Northeastern Mexico. After obtaining the degree he moved to the University of Bremen (Germany) to start his PhD thesis, which was already related to Chile. He looked at changes in the input of terrigenous sediments along the northern and central Chilean continental margin based on sediment cores and surface samples from a German cruise with the R/V Sonne. Dr. Lamy’s research on the Marion Dufresne is titled “Decadal to centennial-scale climate variability during the Holocene and Late Glacial based on long CALYPSO cores off southern Chile”. He and his co-workers are interested in both changes in the ocean (for example sea surface temperatures, salinities) and the continent (rainfall changes, glacier extension) to better understand past climate variability on for geologists short time-scales of decades to centuries. He adds “In order to work in such “short” time-scales, very high sedimentation rates are needed that can be found only in few regions of the world ocean adjacent to the continent with high rainfall and/or glacial activity”. He explains that “Southern Chile is a particularly suitable region for such high resolution studies. In addition, the region is a key area to understand continental climate and ocean variability of the Southern Hemisphere mid-latitudes where large gaps in our knowledge exist (e.g. functioning and long-term behaviour of so-called climate modes like the Antarctic Oscillation and interference with tropical climate variability such as El Nino). These changes are very important for a better understanding of our present climate system and the improvement and validation of climate models for future predictions. Another aspect of the region is the possibility to reconstruct changes in the position and strength of the westerly wind belt that may for example influence atmospheric CO2 contents”. Dr. Elisabeth Michel studied physics for the 4 first years at the University Paris XI, Orsay, and then she did the fifth year and the PhD in Geoscience. She stated that climate Science needs all types of background, and in her lab there are mathematicians, physicians, biologists, chemists, geologists, etc. On the PACHIDERME cruise she and her team’s interests are link to the ocean role in climatic variations and in the global Carbon cycle on time scales of a century to few hundred thousand years. Within the cruise they want to study the story of Antarctic intermediate water and of deep water circulation along the rapid climatic variations of the last glaciation and the deglaciation (last 30 000 years). There is still a lot to understand about the earth climate system. Studying the past climate allows us to discover the different mechanisms of this complex system (interactions between its different components, atmosphere and ocean dynamics, chemistry and biologic production, hydrologic cycle…) and approach its possible behavior in the future. On board Dr. Michel is looking at the reflectance (color) and the density measurements of the sediments. It sometimes gives information on the sedimentation changes and the linked past climate changes. For example the nature of skeleton (calcareous or siliceous) found in the sediments will change the sediments color and density. Siliceous organisms in that area developed in colder climate. Her team’s studies will takes place at the laboratory, when they get back from the cruise. There they will mainly study foraminifera calcacreous shells (few hundred microns) and reconstruct past water temperature, salinity, and main water masses from their isotopic trace metal composition. Dr. Carina Lange is currently a Professor of Oceanography at the University of Concepción where she is involved in graduate teaching, scientific research, and academic administration. Since 2004 she is also the Director of the FONDAP-COPAS Center hosted at the University of Concepción, which was created in 2002. She has an undergraduate degree in biology, and a PhD in biological oceanography from University of Buenos Aires, Argentina. Even before her Ph.D., a series of short- and longer-term stays with Professor Grethe Hasle at the University of Oslo in Norway gave her the opportunity to become an expert in marine diatoms. A UNESCO scholarship took her to the Scripps Institution of Oceanography in California, where she worked for almost eighteen years. It was at Scripps where she initiated the transformation in my career from a marine biologist to a paleoceanographer. Her research interests include temporal and spatial fluctuations in marine productivity/paleoproductivity of upwelling systems (coastal and oceanic) of the world, the use of siliceous microplankton, and marine diatoms in particular, as proxies of present and past ocean productivity, and diatoms (abundance and species composition), production in the euphotic layer, settling through the water column, deposition on the seafloor and final burial and preservation in the sediments. She is also interested in biological response to ocean-climate variability. In relationship to the PACHIDERME cruise she and her colleagues are interested in the fast accumulating sediments of the fjord region and adjacent oceanic areas to study ocean and land variability off southern Chile at decadal to millennial scales. Because the fjord region and adjacent oceanic areas lie under the influence of the Southern Westerlies and associated precipitation patterns, they can contribute to the understanding of land-ocean interactions, and address questions related to present and past fluctuations in the fresh water input and its impact on productivity changes and geochemical cycling of biogeochemically relevant elements. The costal area receives the input of freshwater from the fjord and inland channel system that is fed by river input of ice melting and rainfall origin. High annual rainfall in the fjord region and high mean annual river discharges greatly enhance the supply of terrigenous sediment which leaves its mark in the sedimentary record. This allows for integrating marine and continental proxies in order to understand land-ocean interactions. |
Why are climate change and oceanography each considered as integrated sciences?
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Day 17 Log Hello from 47 degrees 54’ S 74 degrees 29’ W Here is a brief overview of the current weather: Air Temperature: 12.5 degrees Celsius Wind Direction: 35 degrees Wind Speed: 10 kts Air Pressure: 1013.5 mb Humidity: 86 % Cloud Type: stratus Percent Sky Cover: 100% Water Temperature: 12.3 degrees Celsius
We just finished coring near Seno Baker and are meandering our way to a coring site through a narrow fjord that closely resembles a canal and even has the name Messier Canal. As we make our way further south, the layered clothing is making their way out since it is a bit colder down here.
So how many people does it take to run a coring operation on a 120 m vessel? Quite a few! We have 100 people on board that work in one area or another, but all work as a team to accomplish the goals of the cruise. Within a watch there is a scientist in charge, a chief of the watch, a chief of the coring deck, an MST operator, a spectrophotometer operator, 2 sedimentologists, and 8 others (including the teachers) to assist with core processing. All of the above listed positions are filled with personnel who are scientists, science technicians from the labs of the scientists, or students studying at the universities of the Principal Investigators. The scientist in charge oversees all the decisions related to the science operations such as the coring sites and the timing of all the coring operations, whereas the chief of the watch oversees the coordination of all the coring activities. The chief of the deck oversees the core processing (labeling preparing the cores for the lab, etc). The MST and spectrophotometer operators operate their instruments and help out in other areas if necessary. The sedimentologists create the core descriptions and the smear slides, and the 8 other personnel assist with core processing and anywhere else as needed. After the cores make their way back to the respective universities or labs, the scientists, technicians, and students will continue the work started on board the Marion Dufresne.
Also assisting with the functioning of the cruise are 40 others who work on the bridge navigating, on the deck with the equipment, or in the kitchen assisting with meal preparation and serving. There is also a doctor on board should anyone need one, and a number of representatives from IPEV (French Polar Institute) who assist with logistics and computer technology. Those on the bridge keep and eye of the weather using local information as well as information from the computer models developed in France, and they also plan the cruise route after obtaining the proposed coring sites from the Chief Scientists among other tasks such as maintaining the safety of all those on board. Those working on the deck have experience with all types of machinery and know all aspects of the coring equipment. When a new piece of equipment is needed or needs repairing, these workers know how to do it. |
What type of courses would a sedimentologist have to take in college? (Hint: look for a college that offers a graduate degree in geology)
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Day 16 Log Hello from 45 degrees 27’ S 75degrees 28’ W Here is a brief overview of the current weather: Air Temperature: 11.7 degrees Celsius Wind Direction: 16 degrees Wind Speed: 22kts Air Pressure: 1012.7 mb Humidity: 81% Cloud Type: altostratus Percent Sky Cover: 100% Water Temperature: 14.1 degrees Celsius
We are still winding our way through the fjords paying close attention the echo sounder to locate optimal coring sites. At this point we acquired 26 Calypso cores, 9 Casq cores, and 5 HAPS cores. You have been introduced to Dr. Catherine Kissel as the Chief Scientist of the PACHIDERME cruise, but you have not learned much about her science specialty, paleomagnetism. As a paleomagnetist, she is using magnetic properties of the sediment as tracers for paleoenvironmental changes. The sediments are composed of about 90% clay and about 10% biogenic particles. A small fraction of particles are magnetic particles from volcanic origins on land. When the lava cools it records the Earth’s magnetic characteristics, and when the volcanic material weathers and erodes, those particles from the volcanoes are carried to the sea. There are numerous volcanoes in Chile, and the offshore sediments should carry a high quantity of magnetic particles. The magnetic particles contain iron, but some don’t have spontaneous magnetism where the particles respond to a magnetic, they have induced magnetism where the particles become magnetic when placed in a magnetic field. The magnetic particles found in sediment cores will be identified and characterized as to the types (iron oxide, iron sulfide, etc), the nature (physical and chemical properties), grain size and concentration. The chemistry of the magnetic particles will help to determine the environment in which the particle formed (ex: iron sulfide is formed in an oxygen depleted area). Grain size and quantity can give an idea about the precipitation (ex: larger grains mean higher precipitation and greater amounts of erosion). A sensitive magnetometer in the lab (not on the ship) will help to determine the character of the magnetic particles. There are two types of scientists on the PACHIDERME cruise, those studying biogenic sediments, and those studying detrital sediments. Both groups are interested in the magnetic properties of the sediments since parts of the magnetic grains are sensitive to the Earth’s magnetic field when they get deposited and because the Earth’s magnetic field has varied considerably with time, intensity, and also in direction. This can be used to assign a time-scale to the sediments. This is the work she is doing with Dr. Carlo Laj, the leader of the team for that topic. Working with all the scientists, you can see that Dr. Kissel has an important role not only as the Chief Scientist, but also as a key scientist on board the Marion Dufresne. |
Generally speaking, from where is the Earth’s magnetic field generated?
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Day 15 Log Hello from 45 degrees 44’ S 74 degrees 17’ W Here is a brief overview of the current weather: Air Temperature: 11.2 degrees Celsius Wind Direction: 23 degrees Wind Speed: 8 kts Air Pressure: 1015.1 mb Humidity: 85% Cloud Type: stratus Percent Sky Cover: 100% Water Temperature: 12.3 degrees Celsius
We are now into our 3 week out at sea and making excellent progress towards the cruise goals and objectives. The Captain is retiring after this cruise, and to celebrate we took a cruise to the end of a fjord, “parked” the vessel and the Captain took a smaller boat to the beach to grab a sample as a memory of his last cruise. We also had a small celebration after lunch. Here is a closer look at the composition of the sediments in those cores. Marine sediments can be classified by origin, size and distribution of the sediments. The sediments in the ocean can be classified based on their origin as detrital from terrigenous, volcanic, cosmogenic (extraterrestrial) origins, biogenous from shells of mainly planktic organisms), or hydrogenous (or authigenic) from in situ precipitation, alteration/weathering. They are classified by origin using the 30% rule, if there is more than 30% of any type of component in the sediment it will be classified as such. However, it must be kept in mind that there are no pure detrital, authigenic or biogenic sediments; sediments are always mixtures of different components. The sediments can be further classified by size as being gravel (pebbles, cobbles) = > 2mm, sand = 62 µm - 2 mm, silt = 4 - 62 µm, or clay = < 4 µm. The time it takes for each of these sediment sizes to sink to 4km is as follows: pebble = several hours, sand = 2 days, silt = 6 months, clay = 50 yr. The sediments can be further classified by distribution as neritic sediments (on the continental shelves, current or wave deposited, coarse grained, accumulate very rapidly >10 cm/1000 yr); pelagic sediments (in the open ocean, fine grained, deep sea, material that is deposited from suspension fine grained, accumulate slowly 0.1 to 1 cm /1000 yr, clays & biogenic oozes); hemipelagic –(found on outer shelf and slopes, current or suspension mainly sand size or smaller 1-10 cm/1000 yr, muds). The sedimentologists and paleoceanographers on the cruise are interested in all the sediments since the layers and composition in the sediment core can give an indication of when a past event occurred based on its placement in the core, and the microfossils present can give an indication of the past ocean conditions. High annual rainfall in the fjord region and high mean annual river discharges greatly enhance the supply of terrigenous sediment which leaves its mark in the sedimentary record. Microfossils include both the remains of microscopic organisms and small parts of larger organisms. These groups are biologically different from one another; they include single-celled protists, as well as multicellular plants and animals. The animal-like protists include foraminifera and radiolaria. The plant-like protists are diatoms, coccolithophores, and dinoflagellates. The radiolarians and diatoms have shells of silica, whereas all the other protists have shells of calcium carbonate (except dinoflagellates which produce an organic cyst). On a very general global scale, the type and percentages of each of these species can be an indication of cooler or warmer climates. Silica shells are generally associated with cooler waters, and calcium carbonate shells are associated with warmer waters. Of course it gets more complicated than this when we start to talk about why there is a preference of warm versus cold water for these protists. |
Sponge Spicule
Foraminifera
Ash Layer
Diatom
What type of sediments would you expect to find off the coast of New Jersey?
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Day 14 Log Hello from 45degrees 23’ S 73 degrees 29’ W Here is a brief overview of the current weather: Air Temperature: 13.9 degrees Celsius Wind Direction: 335 degrees Wind Speed: 8 kts Air Pressure: 1022.5 mb Humidity: 62% Cloud Type: cirrostratus, cumulus Percent Sky Cover: 25 % Water Temperature: 12.9 degrees Celsius
We are currently winding our way through the fjords searching for a new coring site within the Aysen Fjord. Attempting to find a coring site may be likened to finding a needle in a haystack if the right instruments are not used. As mentioned in a previous log, the topography of the bottoms of the ocean and the fjords is extremely variable, and the sediment depths on both are extremely variable too. With the assistance of the echo sounder we can “see” the sediment depths, and with the skills of navigation officers we can meander safely and efficiently through the ocean and fjords. The ship is outfitted with 2 synchronous electric motors used for propulsion, and 3 diesel generators creating 8250 kWatts of electrical production capability from the diesel fuel. The use of electric motors is necessary to create a “quite” cruising environment for the echo sounder to work effectively. The vessel has the capabilities of moving at a maximum of 17 knots, but we have been cruising between 6-14 knots depending on where we are. To assist Captain Jean-Paul Hedrich and his navigation crew in their jobs, the ship is outfitted with 3 GPS satellite positioning systems, and an “ultra short baseline underwater objects” positioning system, as well as a dynamic vessel positioning system. All of this is used to keep the ship on course while cruising, and in position while coring. An amazing feat given that the vessel is 120m long! Interesting for us (and necessary for the scientists) is that we can watch the position of the ship on nautical charts loaded on the computer system as it navigates from location to location. Of course the paper charts are still an important part of this scientific cruise. They assist The Chief Scientist and Principal Investigators in deciding on preliminary coring sites before the echo sounder gives an idea of sediment depths, and they assist the Captain and Chief Scientist in planning a course to the next coring location. |
Locate the Aysen fjord on a map and create a course from yesterday’s location to this fjord. Why do you think we are coring here?
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Day 13 Log Hello from 44˚4’S 75˚ 7’ W Here is a brief overview of the current weather: Air Temperature: 13.3 degrees Celsius Wind Direction: 7˚ Wind Speed: 3 kt Air Pressure: 1019.5 mb Humidity: 82% Cloud Type: altostratus Percent Sky Cover: 100% Water Temperature: 14 degrees Celsius
We have left Seno Reloncavi and are now in the coring in the Golfo Corcovado. I have heard that the seas could be very rough in this region, but fortunately for all us, we’ve come into calm seas! While out at sea it is very easy to lose your sense of time, but we know its Sunday because there were flaky croissant type pastries out for breakfast! I know you all have been curious about the food we have been eating, and so here is a break from our science discussion to talk a little about the meals on the Marion Dufresne. Meals on a ship during a research cruise are an important aspect of keeping up the good cheer. They are a much needed diversion from the hard work, and a way for everyone to socialize and bond. There is a professional chef and cooks on board that plan the menu for the 90+ people, and make sure that the meals are balanced and delicious. Everyone agrees that there is too much food, but when it is all fresh and delicious it isn’t until after we’ve eaten that we realized that it was too much food! Breakfast is self service between the hours of 7AM and 8:30AM, and consists of juice, coffee, tea, milk, bread/toast, cheese, cold cuts, yogurt, and cereal. We are served lunch and dinner in two shifts by waiters using the European method of serving meaning that they come to each person at the table and serve each part of the meal from a platter. Each table in the dining room has cloth table clothes and cloth napkins, and “real” plates and silverware (like at a restaurant). Lunch and dinner both have an appetizer, entrée with side dishes, and dessert consisting of a selection of cheeses (about 8 different ones) from a cheese tray, and either fruit from a basket or a bowl/plate of a dessert. Some of the foods we have eaten include dishes containing escargot, seafood (shrimp, tuna, mussels, salmon, etc), meats (beef, chicken, pork, lamb, etc) with a variety of cheese, butter, cream, or vegetable sauces. The side dishes have included a variety of potatoes, rice, mixed vegetables, and French bread (of course!). In comparison to our meals in the United States, the lunches on board are no different than dinners in the US. In other words, we are consuming 2 dinners per day, and fortunately there are ways to work off the calories! Except for the tray of cheese and basket of fruit, none of the food during lunch or dinner has been duplicated since the beginning of the cruise! It will be tough cooking for myself when I get back home, but eating processed or fast food won’t be an option after eating the meals I’ve been served on the Marion Dufresne! |
Cabin
Given the fact that you are allowed to bring a limited amount of luggage on board for 3 weeks, what would you bring as a reminder of home and your loved ones?
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Day 12 Log Hello from 42˚8’ S 72˚ 40’ W Here is a brief overview of the current weather: Air Temperature: 13.9 degrees Celsius Wind Direction: 345o Wind Speed: 17 kt Air Pressure: 1021.6 mb Humidity: 77% Cloud Type: altostratus Percent Sky Cover: 100% Water Temperature: 13.9 degrees Celsius
We are still coring within the Seno Reloncavi area, and have already retrieved 2 Calypso, 3 Casq, and 2 HAPS cores. We haven’t introduced the HAPS core yet only because we are just now using it. The purpose of this corer is to remove only the top 50 cm of sediment, and with this the scientists will be gaining the most recent sediment records from the area. Note the picture of this instrument that looks like a tripod with a miniature corer in the center of the apparatus. Now here is the second half of the core processing story…. After the cores have been cut in half, some basic analysis is done on board before they are packaged to ship home. The first stop is the container where the “MST” (Multi-Sensor Track) is located. This is where basic measurements of many parameters are taken using a variety of instruments in a small area. One objective of the MST is to measure the density of the sediment, and this is accomplished by using gamma ray attenuation (reduction). As gamma rays move through the core, the degree in which they are attenuated is directly related to the number of electrons in the gamma ray beam, core thickness and electron density. By measuring the number of unscattered gamma photons that pass through the core, the density of the core material can be determined. In measuring P-wave velocity, a transducer generates ultrasonic compressional waves (P) and sends them across the sediment. Another transducer receives the P-waves, which propagate across the sediment. The MST computer measures the travel time, which is influenced by the temperature of the core. The P-wave transducer provides an estimate the core thickness, and the value of this thickness is used to correct the density measured by the gamma rays. The P-wave velocity is the ratio between the sediment thickness and the pulse travel time in the sediment. The MST also has a special digital camera that measures the reflectance of the red, green and blue lights, and creates high resolution images. Another higher resolution photo is taken of every 2 cm of each core segment before it is packaged up for the lab on land. Another instrument on the MST measures “magnetic susceptibility.” Each substance has magnetic susceptibility, which depends of its constituent materials. Some particles have a low magnetic susceptibility, like micas, feldspars, and some others have high magnetic susceptibility like magnetite or iron oxides. The point sensor is mounted on a moving arm which allows contact with the sediment. A magnetic field is created. The presence of magnetic material near the sensor changes the magnetic field. This variation gives information about the properties of particles which compose the sediment. Magnetic susceptibility can be useful in determining volcanic ash layers and change in the mineral composition. The scientists are not done with the core yet! They still need to do a core description for each and every core segment. Description and characterization of the sediment components provide a very precise documentation about the variations in the stratigraphical and lithological variations. It is very useful for scientists who work in various paleoceanographic fields, because they don’t always have the opportunity to have a look at the original core. Descriptions show variations in sedimentary features with depth, as follows: - climatic events: changes in lithologic layers (foraminifera, opal, microfossils, ...) (Biological proxy) - volcanic events: volcanic minerals like glass which allows to determinate ages (Mineralogical proxy) - earthquake events : changes in the facies (turbidite, grains, etc) (Sedimentological proxy) - disturbances in the sedimentological signal : bioturbation, modification of the deposits structure, diagenesis action, and deformation due to the corer system (Structure proxy) The first step for sediment core description is to look at several parameters and to write all details seen in the core on logging sheets. Then this information is entered in a picture treatment software program such as Adobe Illustrator. To complete the study of the sediment reflectance, a spectrophotometer analysis is made. The spectrophotometer used on board the Marion Dufresne measures the reflectance of the sediment every five centimeters. Those measurements give information about the composition of the sediment: light sediments involve the presence of carbonates whereas dark sediments indicate the presence of organic matter. A “smear slide” is also taken that provides a rapid, simple and cheap examination of the types and quantities of sediments in each core segment. Using a toothpick a small sample is taken from each core segment and from any unusual feature in a core, it is “smeared” on to a slide with a drop of water, set with a mounting medium, and then analyzed under a light microscope onboard and a petrologic microscope in the lab on land. All of this happens very rapidly and efficiently since the science crew acts as a team to accomplish all the tasks of the cruise. Watch for pictures of what we’ve found under the microscope! |
What type of science background do you think the scientists on board the Marion Dufresne have?
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Day 11 Log Hello from 41˚42’ S 72˚ 46’ W Here is a brief overview of the current weather: Air Temperature: 13.6 degrees Celsius Wind Direction: 321˚ Wind Speed: 20 kts Air Pressure: 1019.1 mb Humidity: 60% Cloud Type: cumulus, cirrus, altostratus – at the horizon Percent Sky Cover: 15% all at the horizon Water Temperature: 15.6 degrees Celsius
From reading the science objectives, and hearing about the coring process, you should be getting a sense of how science is done in the field. The scientists on board use inquiry methods like you do when you do a science lab, although there are some differences. In the field the experimental design is very much contingent upon the conditions of the “field” (or ocean in our case). For the scientists on board the condition they are focusing on is sediment depth, and the sediment depths are not the same everywhere, which means the coring sites may change. The echo sounder helps the scientist’s pinpoint optimal coring locations, and sometimes that can take hours. At that point a decision is made between the Chief Scientist and the Principal Investigator interested in that particular site to either continue looking or look for a completely new site. More tomorrow! |
Locate the
major ocean current for this area. What is its name? Which direction
does it flow?
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Day 10 Log Hello From |
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Day 9 Log Hello from 41˚47’S 73˚51’W A few more weather details today: Air Temperature: 16˚C Wind Direction: 106˚ Wind Speed: 12 kts Air Pressure: 1009.8 mb Humidity: 71% Cloud Type: stratus and altostratus Percent Sky Cover: 100% Water Temperature 13˚C
The day started with the processing of a Casq core, and followed with a transit to Ancud to switch our current Chilean pilots with 2 new Chilean pilots. Because we are coring within the fjord regions we are required to have Chilean pilots assist the Captain in navigating the fjords. Although the fjords may be wide, the water depth varies tremendously such that there may only be a narrow channel that can be navigated, but with the assistance of the pilots and the water depth charts, the Captain and his crew can safely navigate the narrow channels within the broad fjords. The pilots remain on board for approximately 7 days and work 5 hour shifts, and then we must cruise to a location to switch pilots.
Today we are reaching our furthest north location, and therefore will be deploying a satellite transmitter for the Argonautica Program. The focus of the Argonautica program is “to better understand the role of oceans in the climate of the Earth thanks to the data from satellites.” The floating ARGOS tracks position and once the data is collected it is transmitted to a satellite where it is then transmitted back to CNES (Centre National d’Études Spatiales) in France. The data can be used to track ocean circulation, and students and teachers can view the data by going to www.cnes-edu.org. Teachers will also find ways use the data in the classroom by visiting the website. Watch the CNES website for the data. ARGOS satellite transmitter ID #:17194. Serial #: 942020 |
Back to yesterday’s question: How is this cruise related to the IPCC report announced on February 2nd? Hint: Find IPCC report in news, locate the 20 page Executive Summary, and see page 8. An Internet search should take you to the .pdf file. You will need to define the term “proxy” in order to understand what proxy data is.
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| Day 8: Hello from 44° 19.81570 S 75° 22.07990 W Here are few vital stats for today: The water temperature is 14.82˚C and the air temperature is 19˚C. The winds are from the 3˚ (North!) at 9 knots (convert knots to mph!). Note that I am now reporting the temperatures in the Celsius scale. Since this is a French vessel, metric units are employed. Convert the units to Fahrenheit if you are unfamiliar with the Celsius scale. Before this trip began you got an overview of what this cruise is all about. Now I’m going to pass along an excerpt from the “official” cruise report that will give you more of an overview of the science objectives of the cruise. You may need to look up some of the terminology, or ask someone for assistance in interpreting the reasons why we are here. Feel free to send your questions my way. 2.
SCIENTIFIC OBJECTIVES OF THE PACHIDERME CRUISE |
In your own words state the objectives of this cruise.
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| Pictures: Dr. Kissel |
Click on pictures to open full size: |
| Day 7: Hello from 45° 49.73130 S 74° 30.59000 W |
Try using Google Earth to zoom into the fjords we navigated through to get to Puerto Chacabuco. Use the latitude and longitude from the log to help. Describe the course the ship had to take from the Pacific Ocean in order to get to Puerto Chacabuco. What is Puerto Chacabuco known for? |
| Day 6: Hello from 46° 4.99230 S 76° 5.99020 W |
Why is the rate of sedimentation greater in the fjord than in the ocean? |
| Day 5: Hello from 48° 8.39270 S 76° 7.44910 W |
Continued from yesterday… where do ocean sediments come from? |
| Pictures: Going Down |
Click on pictures to open full size: |
| Day 4: Hello From 49° 10.05890 S 76° 34.03340 W |
Define the term sediment. |
| Pictures: Punta Arenas Statue
RV Marion Dufresne
Safety
Early AM Rainbow |
Click on pictures to open full size: |
| Day 3: Hello from 49° 46.74650 S 76° 18.35570 W |
Sonar is similar to and a little different from an
echo sounder. How does sonar work? |
| Day 2:
Hello from 52° 39.35790 S 75° 30.96670 W |
The research vessel we are on, Marion Dufresne is 120m long. How many times larger is the Marion Dufresne than a typical school bus? |
| Day 1:
Hello from 53° 35.18630 S 70° 39.64800 W |
Find the Strait of Magellan on a map. What is so
important about this body of water? |
| Pre-trip excursion:
A visit to Monumento Natural Los Pinguinos |
What is the migratory pattern for the Magellanic
Penguin?
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| Daily log coming soon.... | What is the latitude and longitude of Punta Arenas, Chile? Also, what time zone is it in? |
Send your questions to Ms. Holzer at mholzer@monmouth.com
CHS Students: Visit our "Coring the Sea" blog here
Visit the website and blog of Mr. Moore (a teacher at Burlington County Institute of Technology)
"Climate Change at the Arctic's Edge"
Visit Antarctica2007.com
Earth Science Picture of the Day