2021 Virtual Undergraduate Research Symposium
2021 Virtual Undergraduate Research Symposium
Extraterrestrial Fluvial Fans
Extraterrestrial Fluvial Fans
HONORABLE MENTION
PROJECT NUMBER: 55 | AUTHOR: Jack Henry, Geology and Geological Engineering
MENTOR: Piret Plink-Bjorklund, Geology and Geological Engineering
ABSTRACT
On Earth, patterns left by fluvial movements often are indicators of paleoclimates or impactful events which can be utilized to determine an area’s geomorphological history. Tracking and characterizing fluvial movements and patterns left on Earth, and by extension on other celestial bodies, is key to understanding that body’s geologic history. The analysis and differentiation between fluvial structures such as deltas and fluvial fans are important to understanding how these features formed when the contextual evidence of paleobodies of water are removed. Differentiation between these structures are important because deltas deposit into a standing body of water, whereas fluvial fans deposit sediments on land. With an established fan angle database from Earth, the focus of this project turned to Martian fluvial structures. More specifically, structures located in the Eberswalde and Jezero craters were used as central study environments to test our methods. Considering that the Eberswalde Fan is widely accepted to be deltaic in origin, confirming this theory with our current mathematical procedure would allow the team to analyze the debated origins of the Jezero Fan. In addition to recording the fan angles, the additional metrics of node to node channel lengths and widths were also considered to form a more robust conclusion of origin. The reason for the inclusion of these additional metrics being that deltaic fans will have a negative correlation between the length and width of the channel versus its distance away from the apex, while fluvial fans will display no correlation. Thus far, our initial quantitative predictions suggest that the Jezero Fan is fluvial in origin based on these criteria.
PRESENTATION
AUTHOR BIOGRAPHY
Jack is a junior geological engineering major with a focus in mineral resource exploration. For the previous two years, Jack has participated as an undergraduate researcher working under Dr. Plink-Bjorklund and currently Luke Gezovich in the Department of Geology and Geological Engineering. The project focuses on the analysis of extraterrestrial fluvial fans, particularly on Mars, in order to determine ancient paleoenvironments concerning the flow of water.
Hi Jack! This is super cool with a lot of great scientific implications. How would you like to continue this research/ what more do you think we can learn from this?
Hi Sam,
This question is something that I appreciate about research. Investigating one question often led to about ten others. At the moment, a possible future avenue might be to use machine learning to do the same job that took me weeks. This is actually a topic one of my advisors, Luke Gezovich, is working towards. Eventually, the code would be able to classify fans by feeding in pre-classified examples as a database in order to make its own predictions using the same quantitative metrics I used in this project.
Hey Jack. Very interesting that the Jezero crater was then interpreted to be a fluvial fan in origin. Could we then take a step further and interpret what types of processes induced a fluvial fan? I believe these should be different than processes on Earth…
Hello Chad,
Yes, that would be an interesting path for the project. Considering that the fan type is a product of its environment, Martian fans seem like they would be intuitively different. This question might be better answered by different quantitative metrics to analyze characteristics like the type of sediment that is being supplied to the fan, local morphologies surrounding the fan, or even the impact of a different gravitational force.
What would you say are the biggest unknowns and uncertainties in regards to this research project that you have encountered?
Hi Jimmy,
One of the biggest uncertainties we have encountered so far has been the dependence of time and how the fan formed its present geometry. Particularly in the Eberswalde Fan, it is clear that some of the channels deposited over one another throughout time and cross channels. When it comes to collecting angles, it can become difficult to differentiate between an angle formed by this crossing phenomenon or by an actual bifurcation that is useful for determining the fan type. Therefore, collecting an angle that is not indicative of the fan type would skew the data in a more random and less predictable way.
Pretty interesting to use geology to correlate between Earth and Mars.
1) What kind of data would the Perseverance Rover be able to provide?
2) Did you have any issue with photo resolution? Could that have changed your interpretation?
Hello Ian,
Data collected by the Perseverance Rover would have great implications to the project. One of the primary goals that NASA lists is to characterize the geology of Mars by collecting samples in the Jezero Fan. If these samples were to give evidence of a relatively long standing body of water, it could support the idea of a deltaic fan type at this location.
Fortunately, the resolution of the images utilized were exceptional. The HiRISE imaging, provided by the Lunar & Planetary Laboratory at The University of Arizona, was more than satisfactory to track the detailed channels and collect the appropriate data. Although, I could imagine a lower quality image would obscure important details that would be critical to collecting the fan angles.
Excellent work.
Very interesting analysis. I have similar question as Ian Wood. Do you issues with the photo resolution. If you do, what percentage of error resulted from photo resolution
Hello Ahmad,
Great question! Resolution has a huge importance in this detail oriented project. Fortunately, the imaging provided The University of Arizona is fantastic quality and is sufficient for collected the appropriate data. Although, one issue that had to be resolved was importing the images of the martian fans into ArcGIS. During this process, some of the images were misaligned and created discrepancy in some of the channel continuities. This was resolved by using a more appropriate coordinate system to host the images and yield accurate data.
Hi Jack,
Using the correlation of similarities to determine the paleoclimate is astounding, especially for only using satellite images. Similar to Chad’s question, what was the biggest difference you noted between the fluvial and deltaic fans on Earth vs on Mars if any.
Hello Lauren,
Great question! One of the largest differences between the fans located on Earth and Mars is the extreme extraterrestrial environment. Seen in the challenges section, one of the geological features unique to the martian systems are the erosional factors and crater systems. In terms of data collection, these features are essentially missing pages in the fan’s history. Since we are concerned with the trends described by the internal fan geometries as a whole, these features can be considered unproblematic. In future work, we may even be able to predict the fluvial features that existed before the crater systems and erosion took effect.
This is a really cool project. Have you thought about applying this to Titan, and if the different liquid present would change how the fluvial and deltaic fans form?
Hi Alexander,
Thanks for the comment! Yes, we have thought about expanding to Titan. Originally, the “extraterrestrial” portion of the project encompassed both Mars and Titan. Although with the relevance of the Perseverance rover we decided to focus on the current fans of interest. That’s a good point about the different fluid on Titan. I wonder if the less dense methane would create a different erosional/depositional pattern that would impact the metrics we would study.
Hi Jack,
Since there is a loss of data on Mars from erosion I am wondering if there are any techniques available that would help someone map out the deltas while maintain high accuracy?
Hello Annaliese,
You’re right. Resolving this erosion problem may help the team collect an even more robust set of data to characterize the fan while also realizing its full extent. I believe there is imaging available though NASA that shows a better take on what existed before the erosional events. Even though we are not able to see the erased channels today, these types of images show evidence of the material left behind. While not detailed enough to track the now gone channels, the images show the full extent that the toe of the fan reached.