Investigation Of A Potential Endorheic Basin In Terra Cimmeria, Mars

Abstract

Potential endorheic basins that are not contained within an impact crater have been studied only to a limited extent on Mars. These basins, characterised by the absence of outgoing channels, are of particular interest in planetary science due to their potential to preserve evidence for ancient hydrological activity and possible biosignatures [1,2]. This study investigates an inter-crater depression on Mars, located within the Terra Cimmeria region, by analysing both its geological and mineralogical aspects. Remote sensing data were collected, and a detailed geological map of this Martian basin was constructed, revealing various geological features suggesting a past aqueous environment. The analysis of CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) data was then conducted to investigate the mineralogy of the basin-fill deposits. The basin was observed to be rich in pyroxene and olivine, together with evidence of hydrated minerals in some locations.

Introduction

On Mars, open paleolake basins [2] and closed paleolake basins within impact craters [1] have been described often guided by the presence of deltaic bodies and other lacustrine deposits. However, examining terrestrial analogues such as the Makgadikgadi Pans in Botswana, it is revealed that endorheic lake basins do not form only within impact craters on Earth; instead, they can be formed by tectonic processes that result in formation of depressions [3, 4, 5, 6]. Similar tectonic or non-tectonic (i.e., inter-crater) endorheic lacustrine basins might have formed on the Martian surface outside impact craters.

Study Area

The study area lies within the Terra Cimmeria region of Mars' southern hemisphere (34.457°S, 147.973°E). This region features a potential endorheic basin that exhibits characteristics similar to those found near the Huygens Basin on Mars [7, 8]. These endorheic basins can be compared with the Makgadikgadi Pans (Botswana) previously described as potential terrestrial analogues of Mars playa environments [4, 5].

Geological Map

High-resolution Sterio Camera (HRSC), Context Camera (CTX), and High-Resolution Imaging Science Experiment (HiRISE) datasets were used to create a detailed geological map of the Martian basin, constructed using QGIS software, showcasing different geological features present (Fig.1). Digital Elevation Models (DEMs) from the Mars Orbiter Laser Altimeter (MOLA) were also utilised to create a topographical profile of the study area.

Crater counting for age determination

High-resolution imagery in JMARS was utilised to identify and catalogue impact craters within the study area. Each crater was measured and classified based on its size and state of preservation. To reduce secondary crater contamination, craters with a diameter of less than 1 km were avoided. The collected data were then analysed using the Craterstats software [9], which allowed for the estimation of surface ages by fitting the observed crater distributions to established Martian cratering models.

Mineralogical Investigation

Both CRISM hyperspectral (Map-projected Targeted Reduced Data Records-MTRDR) and multispectral (Multispectral Reduced Data Records-MRDR) data were employed for the detailed spectral analysis of the basin. Data were analysed using ENVI version 4.7. Using spectral indexes and browse products such as the MAF and PHY products, the spectral analysis is focused mainly on detecting mafic and hydrated minerals.
The multispectral tile t0472_35s148 was used to globally assess the mineralogy of the study area, including the craters surrounding the basin. Additionally, four CRISM-targeted images (frt0000a3b5_07, frt00009648_07, hrs0000aa66_07, hrl00013bfa_07) were used for detailed investigations.

Results and interpretation

The study area shows a drainage network, consisting of channels and tributaries mapped in the study, which might have created and sustained the lacustrine water body. The crater counting results suggest that this basin dates back to the Late Noachian period, a time when Mars likely had a more temperate climate capable of sustaining liquid water on its surface for extended periods [10]. Our preliminary CRISM analysis within the study area shows the presence of hydrated minerals [Fig.2], which strengthens a possible past hydrological environment in the area. Other minerals observed are olivine and pyroxene, which are consistent with a previous study [11].
This study laid the foundations for understanding the Terra Cimmeria basin as a potential paleo-endorheic basin. 

Figures

Figure 1: Mini Geological Map of the endorheic basin in Terra Cimmeria, Mars

Figure 2: Multispectral tile (t0472_35s148) analysed in PHY browse product with locations of the different regions used for CRISM analysis. (A) Reddish areas are olivine-rich (B). Blue areas indicate possible hydrated minerals. (C)  CRISM spectra with the 1.9 µm feature highlighting the presence of hydrated minerals.

References

[1]    Goudge, T.A., et al. 2015. Icarus 260, 346–367.
[2]    Goudge, T.A., et al. 2012. Icarus 219 (1), 211–229.
[3]    Franchi, F., et al. 2022. Frontiers in Ecology and Evolution, 10, 818417.
[4]    Franchi, F., et al. 2020. Planetary and Space Science, 192, 105048.
[5]    Kahsay, T. H., et al. 2024. Planetary and Space Science, 249.
[6]    Schmidt, G., 2023. Tectonophysics 846, 229678.
[7]    Mukherjee, S., et al. 2020. Geomorphology, 351.
[8]    Singh, D., 2022. Icarus, 372, 114757.
[9]    Michael, G.G., et al. 2010. Earth Planet. Sci. Lett. 294 (3-4), 223–229.
[10]  Andrews‐Hanna, J. C., 2011. Journal of Geophysical Research: Planets, 116(E2).
[11]   Cowart, J. C., et al. 2019. Journal of Geophysical Research: Planets, 124(12), 3181–3204.