Hello Planetary Pals,
This past semester has been quite a roller coaster for me for many reasons. I had a lot on my plate with TA duties and coursework and I, at times, found it very difficult to balance this with my research. But nonetheless, I now feel a great weight has been lifted off my shoulders now that the semester is finished. I am excited to finally get back to business and look forward to finally making decent and substantial progress with my research. This blog post serves as a research update that is long overdue, and also should show the new members of our lab what my research is about.
For the sake of our new colleagues Cailin and Samuel, I’ll give a quick introduction to my research. I am studying a basaltic lava flow in Iceland named Holuhraun. The eruption that created this lava field occurred in 2014-15. Since it’s eruption, parts of it have been slowly covered in a layer of aeolian-deposited sand. One of the initial research goals of my work was to take a ground-penetrating radar to the site and determine the depth of the sand and silt that is obscuring part of the western flank of the field. However, covid has sadly taken away this opportunity as I cannot travel to Iceland this summer. Another part of my research is examining the lava field using C-band radar images obtained by the Sentinel-1 satellites. The site has already been investigated using L-band radar, however my work will be the first to examine it using this new, shorter wavelength. I am using this to quantify the surface roughness of the lava field, and to see how it has changed over time since the eruption began. Through investigating this, we are also hoping to document and explain how surface roughness can be obscured by precipitation.
Since my last research update, I have finally “finished” georeferencing my radar images. Georeferencing has been abysmally slow as I was plagued with errors not only caused by myself but also by ArcMap itself. I was experiencing enormous issues with ArcMap and these issues are still only somewhat resolved at the moment. The issue was that ArcMap would crash seemingly at random every time. I eventually figured out the cause of this issue: the map transformation. After choosing my points while georeferencing, I would try different transformations in the georeferencing toolbox to get the best possible fit to my base map. The options that consistently provided the best matches were the “polynomial” and “align” transformations. I eventually figured out that the maps that I used the polynomial transformations on did not have problems and would not crash when I tried to use them, however the align transformations did. The problem that still arises is that the align function consistently provided the closest match to the base map, while the polynomial ones would still be a little off, even if I used upwards of 50 control points. I now have to do damage control and find which images I used the align function on, and redo those ones. This is my current task and it feels like I am a minesweeper trying to figure out which images work and which ones will crash ArcMap.
I have also started using the raster calculator to create VH/VV images. This is the final step in the image processing that I need to do. Again, this is slowed by the fact that some of the radar images crash when I try to manipulate them, so the process is still slow and ongoing unfortunately.
I have obtained permission to use a facies map of Holuhraun created by Joana Voigt of the University of Arizona. This will allow me to do spatial analysis for each of the different facies. I will be able to quantify the surface roughness in each type of lava in the C-band and can see how this changes over time with erosion and aeolian burial. I will have to figure out how to nudge the facies map to the correct position over the lava field since it is current shifted away and not aligned.
Now that my TA duties are finished and my coursework is over I will finally be able to dedicate most of my time to research and look forward to finally making progress. As well, I am trying to get my old habits back. In January and February, I created a productive work regimen that helped me stay focused and on track. However, by March and April, I found myself lapsing and running into motivation issues and many other dumb brain problems. I am actively trying to turn myself around, and I believe that if things continue on this trend that this summer will be fruitful and productive.