FLASHLINE-16 Science Report-04 06-07-2024

Author: Natasha Nicholson – Chief Science Officer

Flashline Mars Research Station, Devon Island, 75°25’53”N,  89°49’27”W, Nunavut.

Aims:

1. To explore further into the crater area for sites of scientific interest,
2. To acquire a better understanding of the local ecology and geology,
3. To check the solar, galactic, and radon radiation profiles of the area.

Sites of Interest : Geology

‘Final rim’:

The expedition team walked, circuitously, to a ridge approximately 1.67miles due south of the research station. Osinski et al’s paper from 2005 compares different observations and types of measurement and describes two crater rims. The ‘apparent rim’, 23km across, the reach of the concentric fault strike lengths as seen by seismic reflection profiles, and the extent of the negative Bouger gravity anomaly.  The second and ‘final rim’, is 16km across, and described as ‘the diameter of the topographic rim that rises above the outermost slump block not concealed by ejecta…’ We know that the research station is perched on the lip of the 23km wide crater, and theorised that this steep drop beyond the lake was the lip of the ‘final rim’.

Coordinates: 75°24’25.5”N, 89°49’28.5”W.

Pale-grey mound:

There were two types of allochthonous impact melt breccias described in Osinksi et al’s 2005 paper¹: pale yellow–brown and more carbonate-rich, pale grey breccias. We found a pale grey mound and crossed to its base, hoping to encounter some of the pale grey breccias at this mound. Instead, the surface was extremely soft, and we supposed that if the breccias were there, they might be covered by the lacustrine sediments also described in the paper. Ultimately, we did not sample this soft grey silt, but the pure-grey mound stood out clearly in an otherwise mixed environment of brown, dark grey, beige, white and yellow-orange sediments and rocks.

Coordinates: 75°24’20”N, 89°48’24.9”W

Circular patterning:

On the return journey, the crew noted strange circular depressions, clear areas ringed by stones. The group had many theories, all of them biological in nature, imagining goose ground nests, migrating wolf bedding areas, or areas disturbed by grazing muskox. To our surprise, when we returned to the research station, further research revealed that this was most likely just a more extreme example of the ‘patterned ground’ phenomena that we have been seeing all over the area. A phenomenon that is purely thermally and geologically driven, and only occurs in Arctic, Antarctic and high Alpine environments, where the freeze-thaw cycle and expansion of fine-grained soils (as described by Kessler and Werner in 2003²). This provides a valuable reminder that in astrobiology, when looking at pictures and patterns on other worlds, we must be wary to jumping to conclusions of life. Coordinates: 75°24’32.57”N, 89°48’30.95”W

Understanding the terrain:

As stated in the previous science report, none of us are geologists, so all of our conclusions about this environment must be taken with a grain of salt. That said, we have done our best to apply what we have seen to previous findings and geological surveys of the environment, to try and understand the geological history and timescales of the areas we are exploring. The time periods lain bare in this crater range from ~444 million years ago to present day. We have mapped our journey onto a geological map of the area (see appendix A at end of report), which also provides a cross-section of a similar, albeit longer, transect of the crater.

Sites of Interest: Biology

Life in the waterways:

 In total, we crossed four streams on expedition, two before we descended the final rim, and two after. The streams inside the crater appeared much more abundant than the ones outside it, which could be because of their proximity to the crater walls, providing some relative shelter, or due to a higher nutrient content of the area. Whilst looking at the pale grey mound we found a stream with the highest abundance and diversity of life thus far, and also found numerous piles of goose scat, the nutrients from which might have been the cause of this extra abundance.

We took samples of the moss and more of the unidentified ‘land kelp’ from Expedition 1, so that we can run genomic analysis once out of the field. The moss was collected in the same way we collected the algae; loosening with a sterile lab scoop, extracting with blunt-nosed tweezers, and placing in a 50ml falcon tube with water from the stream it was growing in. The ‘kelp’ did not need to be loosened, it lay on the wet ground or in the water as though dropped there.

Coordinates: 75°24’20”N, 89°48’24.9”W

Predators:

We found potential signs of predators in the area: fox scat on the plane on our way across the plain (Fig. 5), a strange conglomeration of what appeared to be small animal bone fragments in scat, likely quite old, possibly from a wolf³  (Fig. 6), and a large bone fragment, possibly part of a muskox femur (Fig. 7), though it is hard to say whether its death was an act of predation or not.

Algal streak:

Returning north from the crater, we discovered a second streak of green algae, around 15ftx10in, slightly longer than the one beyond Trinity Lake, but not as thick, except for near the top. It remains a mystery why, with so many small running streams and areas of run-off, only these two algal streaks have been found in all this area, and that they seem so precisely contained. We sampled this using the same protocols as detailed in Science report 3.

Coordinates: 75°24’32.43”N, 89°48’30.24”W.

General flora and fauna:

In addition to the life already mentioned in the crater and surrounding streams, we found and photographed more flowers, flowering arctic willows and thick bryophytes along the expedition, and saw some small, winged insects and even some bumblebees. We also saw a snow bunting ‘Plectrophenax nivalis’, a distant seagull, and a goose descending to a point upstream of where we stopped for lunch.  The sheer quantity of life in a landscape that looks so empty and beautiful brings to mind from the opening paragraphs of White Fang:

‘…A vast silence reigned over the land. The land itself was a desolation, lifeless, so lone and cold that the spirit of it was not even sadness… It was the Wild, the savage frozen-hearted Northland Wild.
   But there was life, abroad in the land and defiant.’

Radiation

Radiation was measured using the Radiacode portable dosimeter, which tracked radiation levels at 2 minute intervals for the duration of the expedition.

References

1. Osinski, G.R., Lee, P., Spray, J.G., Parnell, J., Lim, D.S., Bunch, T.E., Cockell, C.S. and Glass, B., 2005. Geological overview and cratering model for the Haughton impact structure, Devon Island, Canadian High Arctic. Meteoritics & Planetary Science, 40(12), pp.1759-1776.

2. Kessler, M.A. and Werner, B.T., 2003. Self-organization of sorted patterned ground. Science, 299(5605), pp.380-383.

3. Lloveras, et al. 2020. Distinguishing the taphonomic signature of wolves from humans and other predators on small prey assemblages. Scientific Reports, 10(1), p.8030.

Appendix A