Author Archive

Subscribe

Moving to Kelly Lake – and putting our knowledge to the test

Posted on July 6th, 2011 by Margarita Marinova

After three Deepworker seasons at Pavilion Lake – and multiple years of science scuba exploration before that – we are moving to Kelly Lake this year. You already knew that – but how do the two tie together? What will be similar and what will be different?

Kelly Lake and Pavilion Lake are similar in that they both have microbialites, and with similar morphologies (shapes) too! But at Pavilion the microbialites are just about everywhere – while at Kelly Lake they are only in a few locations. Why is that? We have done some scuba diving in Kelly Lake, but because of the limitations of how much time we can spend underwater, we haven’t been able to really map where the microbialites occur. So this year we’ll use the Deepworker submersibles to really get a close look at where all the Kelly microbialites are and how they look. They could all be similar to what we see at Pavilion – but until we go and look we just don’t know.

And speaking of mapping – we already have bathymetry (depth) and SONAR (surface hardness and roughness) data for Kelly Lake, which gives us at least some idea of where to go look for what we think are microbialites. But this data also shows us some interesting features that we haven’t seen in Pavilion Lake. For example, some of the sonar images look like gullies – the scours that are formed when water running down a hill causes a landslide. But this is underwater, so how did it form? Or there are some wavey features – what about those? Again, until we go and look, we just don’t know.

Our move to Kelly Lake is also interesting in an operational sense. After three years of having the submarines at Pavilion Lake, we largely knew what to expect. We knew how to plan missions, how long they would take, where to find the type of microbialites that a specific scientist was interested in. Because Kelly Lake is new, we have put together everything that we had learned from Pavilion Lake – both in terms of the science and the submarine exploration – and are using it to exploring our new Kelly Lake world. We have the bathymetry and sonar data, which are like having remote sensing data for another planet. So given that, how well can we do in planning the best missions, with the highest productivity and success for the selected tasks? This is really like going to another planet and using all of our training! The added pressure here is that we expect to only spend one season at Kelly Lake with the Deepworkers, which means that we have to do it all the first time: from general exploration of the lake, to selecting the best samples to collect, to which microbialites and features are of the greatest interest and should be imaged and explored the most.

This move isn’t to say that we have learned everything that we wanted to know about Pavilion Lake, but it does mean that our Deepworker exploration there has already yielded detailed maps of morphology distribution and mapping in the lake, and future work can focus on understanding choice locations through scuba diving. It is time to move to a lake like Kelly, where similar microbialites are present, but the environment is just different enough that it will put our understanding of how everything forms to the test.

Analogue science – above the water at Desert RATS

Posted on September 11th, 2010 by Margarita Marinova

Rocks, rocks everywhere! This time we are not in the underwater wonder of Pavilion Lake, but in the desert and volcanic fields between Flagstaff and the Grand Canyon in Arizona.

But wait! Is that a rover peaking from behind that volcano?

Exploring these volcanic fields are rovers, habitats, robots small and big – all part of the NASA Desert RATS project. The goal: test equipment and procedures for planetary exploration of the Moon, Mars, and beyond. It’s an amazing operation where crews in rovers explore the surface, bring samples back to the habitat to be examined, robots small and big map the surroundings, and science crews back on “Earth” follow and coordinate it all. What does that add up to? Over 150 people learning about operations, science, engineering, and human factors to help us plan our next big exploration and science adventure in space!

At the start of the mission, the rover is docked to the habitat. For the following 7-day mission, the crew will explore and live in the rover. (Image: D. Reid)

This week I am part of the Strategic Science Operations Team (SSOT), which is the NASA way of saying “look at the day’s science, how does it all fit into understanding the area’s geology, and decide what should be studied the next day!” Our day starts after everyone else is done, at 8pm, since we need the data from the rover crews, the reports from the command center, and the reports of the day-time science team. Starting at 8pm, we put all of this information together to really understand what new discoveries were made during the day. My role is specifically to analyze the data from Rover A: looking at video notes, images and samples that the crew took, as well as notes and GigaPan images by the day-time science team.

The portable "Houston" in the Arizona Desert. This is the command center for the Desert RATS project. (Image: D. Reid)

It’s amazing to see the close-up images that the crew takes, and just how much more you can see and understand from walking across the area compared to orbital images! It’s like seeing a picture of New York or Paris, compared to actually going there! The crew can really give us a better perspective on what it is they see, and their interpretations of the geology are invaluable!
By 5am we have to finish our analysis, the planning for the following day, the new day plans for the crew – and uploaded it all to the command center.

At base camp, seeing all the pieces come together, I stand in awe. This is what it means to plan for a monumental mission like exploring the Moon. There are so many pieces, and they all have to come together flawlessly. A robot purrs to life as it starts moving up the hill to provide better communications. The crew is getting ready for another day of exploration, reading their updated day plans sent from the science team during the night. The day-time science team is ready and counting down the minutes to the morning brief with the crew. In the quietness of the desert, everyone is ready to go, and the sun comes up as if to give the go-ahead for another day of exploration.

~ mars.

Ask a Scientist: Are scientists looking for similar lakes around the world that might have these microbialite structures?

Posted on June 27th, 2010 by Margarita Marinova

Question from Astrobiology Magazine regarding other microbialite supporting lakes around the world. Answered by Dr. Margarita Marinova. To ask your question, visit www.astrobio.net and search for the Pavilion Lake Research Project, or click this link: www.tinyurl.com/askplrp.

YouTube Preview Image

Sometimes you get some answers, sometimes you’re left with more questions

Posted on July 12th, 2009 by Margarita Marinova

Coming back from a great flight in the subs, I am even more excited about the lake! What an amazing place!

I had a great flight – the goal was to fly a contour at 15m depth on the east side of the South Basin (north section). That was just fascinating! A specific objective was to identify rock slides, to enable the afternoon flight to document and sample some of these rock slides. Why? Well, one of our hypotheses is that microbialites need rocks to start their growth. The sediment around is so soft, that it seems hard for any large structure to just grow in it. Using video to image these rock slides, we find that at significant depth we just see the rocks. As we get shallower first there is a thin cover of microbialites on the rocks, and then with increasingly shallower depth the microbialites get bigger and bigger! At this point there is no sign of the rock that’s likely underneath. So does this prove that microbialites always need a rock? Well not really! Just nearby there were landslides with no microbialites on them. Why is that? It’s the same type of rock, likely the same lake chemistry, and likely the same biology. But there is such a difference! Then later in the dive I also found areas with scattered microbialites, which certainly didn’t look like they depended on rocks for their growth. Examples of these relationships are seen throughout the lake, but it is this field season that we are meticulously documenting them. And while we are certainly showing some relationships are true, what we see raises even more questions!

Another big question we are asking is if the microbialites are currently growing. On this dive it was sad for me to see that there was a lot of trash on the lake bottom. But this trash is also like a natural experiment to look at microbialite growth. In this case, we can look at whether there is anything growing on the trash, or also on trees that have fallen into the lake. In the case of trash, we know it got there less than ~100 years ago, and a lot of the trash in this area was covered with about 0.5 cm (1/5 inch) of microbialite growth! So we now know that the microbialites are currently growing, at least in that part of the lake. So then we ask why is there such a difference in sizes for different parts of the lake? Just a few hundred meters south of my dive, Mike Gernhardt was exploring unusually large structures: 2 meters tall, by 3 meters wide (6 ft tall, by 10 ft wide). Where I was flying, most of the structures were small: maximum height of 20 cm (8 inches). So why is there such a difference? Is microbialite growth constant, or does their growth effectively turn on and off? Do the microbialites grow faster in one area than another because of slight water chemistry differences? Or something else? We haven’t seen any of these chemistry differences yet, but it could be something we haven’t measured … yet.

We started out 5 years ago with so many questions. Now we have more and more questions, but it is also nice to see that some answers are coming in as well. As we analyze the wealth of data we are collecting with the DeepWorker submarines, we are sure to answer more and more of these intriguing questions.

-Mars

Focusing on the details: 2009 DeepWorker Science Goals

Posted on June 22nd, 2009 by Margarita Marinova
Submersible tracks from the 2008 field season. Satellite image from Google Earth.

Submersible tracks from the 2008 field season. Satellite image from Google Earth.

As the field season nears, and everyone is busy finishing up all those details necessary to make our time in the field run smoothly, it’s important to refocus on our science goals for this year.

To quickly recap last year’s field season : our science pilots managed to explore most of the lake, giving a wealth of video footage and personal observations for the entire science team to analyze during the past year. You can see just how much of the lake we covered last year from all the submarine tracks! For the 2009 field season we have two main goals: to finish exploring some of the areas that we didn’t reach last year (you never know what’s hiding in the dark!); and to explore in detail the areas that we found to be particularly fascinating from our analysis of the 2008 data.

Following-up on the extensive exploration from last year, we are turning our attention to understanding some of the already identified features and trends, and using these to answer some big questions. In the lake we find microbialite structures that vary in shape and size. Some lake bottom areas are covered with the microbialites, while others have just sediment, or algae, or rocks from landslides. So why is there such a variation in what we find in the lake? How do the microbialites form? What sets their shape, their size, their distribution? And what can they tell us about the preservation of biosignatures – the fossils of microorganisms? These are hard questions that geobiologists have been trying to answer for decades, and we think that studying Pavilion Lake will contribute to the understanding of microbialites throughout Earth’s history. To tackle these questions, this field season we will be using the DeepWorkers to get detailed imaging and data at previously identified areas of interest.

Microbialite structures among the chara (algae). Are the microbialites using the chara as a base to grow on?

Microbialite structures among the chara (algae). Are the microbialites using the chara as a base to grow on?

Analysis of last year’s DeepWorker observations gave some surprising results, but also showed some possible trends that need to be investigated further. Last year we were surprised that the macro-morphology – the large-scale shape of the microbialite structures – was not strictly correlated with depth, like we thought it would be. So this year we hope that detailed observations needed to answer some smaller questions will ultimately help us answer our big questions. Some smaller questions we’re asking are: what are the microbialites growing on? Do they need a rock as a growing base, or algae, or do they just sit in the sediment? And does the growing medium have an effect on the shape or size of the microbialite? What about the small-scale structure (micro-morphology)? Microbialites with similar macro-morphologies can still be composed of differently shaped and sized components. The answers from all of these smaller questions will hopefully shed light on the bigger questions.

Every year we get some answers, and come up with even more questions. But that’s why this project is fascinating: Pavilion Lake is such a complex system! Little by little – by asking the right questions – the answers are coming together and we are starting to understand Pavilion Lake.

~Mars

One microbialite, Two microbialites, Bulbous microbialite, Pointy microbialite

Posted on March 25th, 2009 by Margarita Marinova

Welcome to the Pavilion Lake microbialite garden! To the right you will find the cauliflowers, straight ahead are the cauliflowers with chimneys, to the left we see the artichokes, and off in the deep end you can find some corals!

Cauliflowers with chimney structures

Cauliflowers with chimney structures

We didn’t plant the microbialite garden, but the Pavilion Lake Research Project team is there to study it. Microbialites are carbonate structures that form in water with the help of microorganisms. Commonly we see carbonates as limestone, but in certain special cases – often when life is involved – the carbonate precipitates to form some very unique structures. These microbialites are interesting because they can help us understand the types of structures that microorganisms form and the biological signatures they leave behind. We can then use this information to study similar structures from over 2.5 billion years ago. Microbialites are present in a number of lakes around the world, but what makes Pavilion Lake so special is the remarkable diversity! Not only is the lake full of microbialites, but the structures range in size, morphology (shape), and depth!

Artichoke structure

Artichoke structure

This is where our garden analogy comes in. As we explored the lake, we saw that the great diversity of microbialites fell into four general morphological categories: cauliflower, chimney, artichoke, and coral. From the four locations around the lake that we had decided to study intensely at the start of the project, these morphology types seemed to correlate with depth. We found the bulbous structures in the shallows, with chimneys, artichokes, and coral-like structures at increasing depths.

The microbialite structures are complex, and truly require a team with diverse skills and interests to study them. For me, the influence of physical factors on where and how the microbialites grow is incredibly interesting! Some specific questions that we are asking are: does the type of observed structure correlate with amount of light at that location? Is the mineral composition of the microbialites different between structures? Does the depth or the type of material on the lake bottom determine what type of microbialite grows? Studying the effects of light and temperature tell us whether biology is involved, as photosynthesis and therefore rate of growth depend on these parameters. Conversely, a relationship between mineralogy and morphology could mean a more abiological and chemical control on the shapes of the microbialites. One way of answering these questions is by placing sensors on the lake bottom – near microbialite structures – and recording the environmental conditions that the microbialites feel throughout the year. To assess environmental conditions we must collect years of data to be confident in the trends: for example, just because one year is cloudy and cold doesn’t mean this is always the case!

Cauliflower structures

Cauliflower structures

Another important approach that was started last year has been the use of the Deepworker submersibles. With these submarines we have been able to take high definition video of everything that the pilot sees: truly exploring the lake bottom without the constraints of scuba diving. We have used the video collected by the subs to map the lake bottom, that meant looking at more than 70,000 images, but it was well worth it! The mapping allowed us to really understand the distribution of microbialites over the entire lake and be able to more confidently say if morphology type correlates with factors like depth or lake bottom material. We certainly were in for some surprises when it came to the distribution of morphologies! For example we found that artichoke structures are distributed over a much larger range of depths than we had previously thought, and this coming summer we will be testing the hypothesis that the microbialites need a hard surface, like a rock, to start growing.

Coral-like structures in the deep end

Coral-like structures in the deep end

There is a lot more work to be done in understanding these microbialite structures. Pavilion Lake keeps us coming back with its fascinating science questions and enchanting structures: the depths of the lake are a window to the past, yet rooted in the present. Year after year we use these structures as a key to understanding the oldest life, the smallest organisms, and the most wondrous lake in beautiful British Columbia. What’s not to love?

:-) Mars