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Open AccessOpen Access JUSTC Earth and Space 25 June 2024

Discovery of a geomorphological analog to Martian araneiforms in the Qaidam Basin, Tibetan Plateau

  • 1.

    Laboratory of Seismology and Physics of Earth’s Interior, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China

  • 2.

    Department of Earth Sciences, The University of Hong Kong, Hong Kong 999077, China

  • 3.

    CAS Center for Excellence in Comparative Planetology, Hefei 230026, China

Cite this:
https://doi.org/10.52396/JUSTC-2023-0164
More Information
  • Author Bio:

    Shengxing Zhang is a Ph.D. candidate at the University of Science and Technology of China. His research mainly focuses on numerical simulations, geodynamics, and Martian analogs

    Yiliang Li is an Associate Professor at The University of Hong Kong. He received his Ph.D. degree from the University of Science and Technology of China in 1999. His research mainly focuses on the mineral records of the early life on Earth and Martian analogs

    Wei Leng is a Professor at the University of Science and Technology of China. He received his Ph.D. degree from the University of Colorado Boulder in 2010. His research mainly focuses on geodynamics and planetary science

  • Corresponding author: E-mail: yiliang@hku.hk; E-mail: wleng@ustc.edu.cn
  • Received Date: 05 November 2023
  • Accepted Date: 15 February 2024
    • Available Online: 25 June 2024
    Abstract

  • Abstract

    Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars. A gas erosion process driven by the seasonal sublimation of CO2 ice was proposed as an explanation for their formation, which cannot occur on Earth due to the high climatic temperature. In this study, we propose an alternative mechanism that attributes the araneiform formation to the erosion of upwelling salt water from the subsurface, relying on the identification of the first terrestrial analog found in a playa of the Qaidam Basin on the northern Tibetan Plateau. Morphological analysis indicates that the structures in the Qaidam Basin have fractal features comparable to araneiforms on Mars. A numerical model is developed to investigate the araneiform formation driven by the water-diffusion mechanism. The simulation results indicate that the water-diffusion process, under varying ground conditions, may be responsible for the diverse araneiform morphologies observed on both Earth and Mars. Our numerical simulations also demonstrate that the orientations of the saltwater diffusion networks are controlled by pre-existing polygonal cracks, which is consistent with observations of araneiforms on Mars and Earth. Our study thus suggests that a saltwater-related origin of the araneiform is possible and has significant implications for water searches on Mars.

    Graphical abstract

    Araneiforms on Earth and Mars may have a similar saltwater-related origin.

    Abstract

    Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars. A gas erosion process driven by the seasonal sublimation of CO2 ice was proposed as an explanation for their formation, which cannot occur on Earth due to the high climatic temperature. In this study, we propose an alternative mechanism that attributes the araneiform formation to the erosion of upwelling salt water from the subsurface, relying on the identification of the first terrestrial analog found in a playa of the Qaidam Basin on the northern Tibetan Plateau. Morphological analysis indicates that the structures in the Qaidam Basin have fractal features comparable to araneiforms on Mars. A numerical model is developed to investigate the araneiform formation driven by the water-diffusion mechanism. The simulation results indicate that the water-diffusion process, under varying ground conditions, may be responsible for the diverse araneiform morphologies observed on both Earth and Mars. Our numerical simulations also demonstrate that the orientations of the saltwater diffusion networks are controlled by pre-existing polygonal cracks, which is consistent with observations of araneiforms on Mars and Earth. Our study thus suggests that a saltwater-related origin of the araneiform is possible and has significant implications for water searches on Mars.

    • Public Summary

    • The first terrestrial analog for Martian araneiforms was identified in the Qaidam Basin, Tibetan Plateau.
    • Quantitative geomorphological analysis has demonstrated the similar fractal features between Qaidam and Martian araneiforms.
    • The formation of araneiforms can be explained by the erosion of upwelling salt water from the subsurface.

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    • References(36)
  • [1]
    Hao J, Michael G G, Adeli S, et al. Araneiform terrain formation in Angustus Labyrinthus, Mars. Icarus, 2019, 317: 479–490. doi: 10.1016/j.icarus.2018.07.026
    [2]
    Hansen C J, Thomas N, Portyankina G, et al. HiRISE observations of gas sublimation-driven activity in Mars’ southern polar regions: Ⅰ. Erosion of the surface. Icarus, 2010, 205 (1): 283–295. doi: 10.1016/j.icarus.2009.07.021
    [3]
    Portyankina G, Hansen C J, Aye K-M. Present-day erosion of Martian polar terrain by the seasonal CO2 jets. Icarus, 2017, 282: 93–103. doi: 10.1016/j.icarus.2016.09.007
    [4]
    Piqueux S, Byrne S, Richardson M I. Sublimation of Mars’s southern seasonal CO2 ice cap and the formation of spiders. Journal of Geophysical Research: Planets, 2003, 108 (E8): 5084. doi: 10.1029/2002je002007
    [5]
    Kieffer H H, Christensen P R, Titus T N. CO2 jets formed by sublimation beneath translucent slab ice in Mars’ seasonal south polar ice cap. Nature, 2006, 442 (7104): 793–796. doi: 10.1038/nature04945
    [6]
    Kieffer H H, Titus T N, Mullins K F, et al. Mars south polar spring and summer behavior observed by TES: Seasonal cap evolution controlled by frost grain size. Journal of Geophysical Research: Planets, 2000, 105 (E4): 9653–9699. doi: 10.1029/1999je001136
    [7]
    Hao J, Michael G G, Adeli S, et al. Variability of spider spatial configuration at the Martian south pole. Planetary and Space Science, 2020, 185: 104848. doi: 10.1016/j.pss.2020.104848
    [8]
    Piqueux S, Christensen P R. North and south subice gas flow and venting of the seasonal caps of Mars: A major geomorphological agent. Journal of Geophysical Research: Planets, 2008, 113 (E6): E06005. doi: 10.1029/2007je003009
    [9]
    Schwamb M E, Aye K-M, Portyankina G, et al. Planet Four: Terrains–Discovery of araneiforms outside of the South Polar layered deposits. Icarus, 2018, 308: 148–187. doi: 10.1016/j.icarus.2017.06.017
    [10]
    Mc Keown L E, Diniega S, Bourke M C, et al. Morphometric trends and implications for the formation of araneiform clusters. Earth and Planetary Science Letters, 2023, 607: 118049. doi: 10.1016/j.jpgl.2023.118049
    [11]
    Portyankina G, Hansen C J, Aye K-M. How Martian araneiforms get their shapes: morphological analysis and diffusion-limited aggregation model for polar surface erosion. Icarus, 2020, 342: 113217. doi: 10.1016/j.icarus.2019.02.032
    [12]
    De Villiers S, Nermoen A, Jamtveit B, et al. Formation of Martian araneiforms by gas-driven erosion of granular material. Geophysical Research Letters, 2012, 39 (13): L13204. doi: 10.1029/2012gl052226
    [13]
    Mc Keown L, McElwaine J N, Bourke M C, et al. The formation of araneiforms by carbon dioxide venting and vigorous sublimation dynamics under Martian atmospheric pressure. Scientific Reports, 2021, 11 (1): 6445. doi: 10.1038/s41598-021-82763-7
    [14]
    Masek J G, Turcotte D L. A diffusion-limited aggregation model for the evolution of drainage networks. Earth and Planetary Science Letters, 1993, 119 (3): 379–386. doi: 10.1016/0012-821x(93)90145-y
    [15]
    Dang Y, Xiao L, Xu Y. Polygons. In: Mars on Earth: A Study of the Qaidam Basin. Singapore: World Scientific, 2021: 199–247.
    [16]
    Lai Z, Mischke S, Madsen D. Paleoenvironmental implications of new OSL dates on the formation of the “Shell Bar” in the Qaidam Basin, northeastern Qinghai-Tibetan Plateau. Journal of Paleolimnology, 2014, 51 (2): 197–210. doi: 10.1007/s10933-013-9710-1
    [17]
    Anglés A, Li Y. The western Qaidam Basin as a potential Martian environmental analogue: An overview. Journal of Geophysical Research: Planets, 2017, 122 (5): 856–888. doi: 10.1002/2017je005293
    [18]
    Li J, Li T, Ma Y, et al. Distribution and origin of brine-type Li-Rb mineralization in the Qaidam Basin, NW China. Science China Earth Sciences, 2022, 65 (3): 477–489. doi: 10.1007/s11430-021-9855-6
    [19]
    Xiao L, Wang J, Dang Y, et al. A new terrestrial analogue site for Mars research: The Qaidam Basin, Tibetan Plateau (NW China). Earth-Science Reviews, 2017, 164: 84–101. doi: 10.1016/j.earscirev.2016.11.003
    [20]
    Zhao J, Shi Y, Xiao L. Valleys. In: Mars on Earth: A Study of the Qaidam Basin. Singapore: World Scientific, 2021: 249–273.
    [21]
    Horton R E. Erosional development of streams and their drainage basins; hydrophysical approach to quantitative morphology. Geological Society of America Bulletin, 1945, 56 (3): 275–370. doi: 10.1130/0016-7606(1945)56[275:EDOSAT]2.0.CO;2
    [22]
    Chicco D, Warrens M J, Jurman G. The coefficient of determination R-squared is more informative than SMAPE, MAE, MAPE, MSE and RMSE in regression analysis evaluation. PeerJ Computer Science, 2021, 7: e623. doi: 10.7717/peerj-cs.623
    [23]
    Witten T A, Sander L M. Diffusion-limited aggregation, a kinetic critical phenomenon. Physical Review Letters, 1981, 47 (19): 1400–1403. doi: 10.1103/physrevlett.47.1400
    [24]
    Sui S G, Gong S L, Wang T. Study on Laplace growth and diffusion limited aggregation with material properties. Advanced Materials Research, 2013, 703 (2): 71–74. doi: 10.4028/www.scientific.net/amr.703.71
    [25]
    La Roche H, Fernández J F, Octavio M, et al. Diffusion-limited-aggregation model for Poisson growth. Physical Review A, 1991, 44 (10): R6185–R6188. doi: 10.1103/physreva.44.r6185
    [26]
    Wang S, Ji H, Zhang Y, et al. Research on the model improvement of a DLA fractal river network. IEEE Access, 2020, 8: 100702–100711. doi: 10.1109/access.2020.2997923
    [27]
    Halsey T C. Diffusion-limited aggregation: A model for pattern formation. Physics Today, 2000, 53 (11): 36–41. doi: 10.1063/1.1333284
    [28]
    Prieto-Ballesteros O, Fernández-Remolar D C, Rodríguez-Manfredi J A, et al. Spiders: Water-driven erosive structures in the southern hemisphere of Mars. Astrobiology, 2006, 6 (4): 651–667. doi: 10.1089/ast.2006.6.651
    [29]
    Boynton W V, Feldman W C, Squyres S W, et al. Distribution of hydrogen in the near surface of Mars: Evidence for subsurface ice deposits. Science, 2002, 297 (5578): 81–85. doi: 10.1126/science.1073722
    [30]
    Bridges J C, Schwenzer S P. The nakhlite hydrothermal brine on Mars. Earth and Planetary Science Letters, 2012, 359–360: 117–123. doi: 10.1016/j.jpgl.2012.09.044
    [31]
    Rivera-Valentín E G, Gough R V, Chevrier V F, et al. Constraining the potential liquid water environment at Gale Crater, Mars. Journal of Geophysical Research: Planets, 2018, 123 (5): 1156–1167. doi: 10.1002/2018je005558
    [32]
    Cassanelli J P, Head J W. Lava heating and loading of ice sheets on early Mars: Predictions for meltwater generation, groundwater recharge, and resulting landforms. Icarus, 2016, 271: 237–264. doi: 10.1016/j.icarus.2016.02.004
    [33]
    Li C, Zheng Y, Wang X, et al. Layered subsurface in Utopia Basin of Mars revealed by Zhurong rover radar. Nature, 2022, 610 (7931): 308–312. doi: 10.1038/s41586-022-05147-5
    [34]
    Ojha L, Wilhelm M, Murchie S, et al. Spectral evidence for hydrated salts in recurring slope lineae on Mars. Nature Geoscience, 2015, 8 (11): 829–832. doi: 10.1038/ngeo2546
    [35]
    Dundas C M, Bramson A M, Ojhal L, et al. Exposed subsurface ice sheets in the Martian mid-latitudes. Science, 2018, 359 (6372): 199–201. doi: 10.1126/science.aao1619
    [36]
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    Figure  1.  Various araneiform morphologies were observed in the south polar region of Mars. (a) The early stage of the araneiform (ESP_023600_1095). (b) The middlescence stage of the araneiform (ESP_066587_0790). (c) The mature stage of the Martian araneiform with a good fractal structure (ESP_014255_0980). (d) The shaded relief map of the south polar region of Mars. The blue stars represent the locations of the corresponding araneiforms. (e) Parallel araneiforms that developed along a ditch (ESP_056038_1070). (f) Araneiform networks with meandering and wide channels (ESP_029613_0995). (g) The half araneiform developed under a dune (PSP_006204_0985). (h) Fat araneiforms (ESP_066555_0870).

    Figure  2.  Martian araneiforms growing on terrains with different polygonal patterns. (a) Araneiforms on a hexagonal-dominated polygon terrain (ESP_052822_2615). (b) Two araneiform structures on a mixed polygon terrain (ESP_011491_0985). (c) A series of araneiforms on a terrain with fine polygonal grids (ESP_066461_0765). (d) Araneiforms on a pentagon-dominated polygon terrain (ESP_066595_0750). (e) The araneiform on a terrain with quadrangular polygons (ESP_056927_0940). (f) The araneiform on a terrain with mixed polygons (ESP_066587_0790). (g) Polygonal relicts with raised rims.

    Figure  3.  The geographic background of the spider terrain in the Qaidam Basin (Google satellite images taken on November 28, 2012).

    Figure  4.  The Qaidam spiders with different morphologies. (a) The early stage of the Qaidam spider. (b) The middlescence stage of the Qaidam spiders. (c, d) Parallel spiders formed along artificial saltwater canals. (e) A fat spider. Figs. 4a–c & 4e are Google satellite images taken on November 28, 2012. Fig. 4d is the aerial image taken during our fieldwork in July 2021. (f–g) Spiders growing on a polygonal terrain (Google satellite images taken on November 28, 2012). (h) Polygonal relics with raised rims (aerial image taken during our fieldwork in July 2021). To clearly show the spider networks, some parts of them in Fig. 4f are marked in blue.

    Figure  5.  The formation mechanism and fractal analysis results of araneiforms. (a) The formation mechanism of the Qaidam spiders. The lighting effect is used to enhance the aesthetic appeal of the blue brine. (b) The calculated branching ratios of the selected Martian araneiforms and the Qaidam spiders. The color represents the R-squared value (a larger value means a smaller deviation from Horton’s law). The gray area is the range given in a previous study of Martian araneiforms[11]. The orange region is the range of our DLA simulation results (100 tests for a free-growing araneiform in Fig. 6a).

    Figure  6.  Simulation results of water-diffusion patterns with different sources and ground conditions. (a) A free-growing araneiform. (b) Parallel araneiforms originating from a ditch. (c) A fat araneiform originating from an upwelling pool. (d) A semiemergent araneiform in which water diffusion is prohibited in the gray region. (e) The araneiform growing on a pre-existing quadrangular network. (f) The araneiform growing on a pre-existing hexagonal network.

    [1]
    Hao J, Michael G G, Adeli S, et al. Araneiform terrain formation in Angustus Labyrinthus, Mars. Icarus, 2019, 317: 479–490. doi: 10.1016/j.icarus.2018.07.026
    [2]
    Hansen C J, Thomas N, Portyankina G, et al. HiRISE observations of gas sublimation-driven activity in Mars’ southern polar regions: Ⅰ. Erosion of the surface. Icarus, 2010, 205 (1): 283–295. doi: 10.1016/j.icarus.2009.07.021
    [3]
    Portyankina G, Hansen C J, Aye K-M. Present-day erosion of Martian polar terrain by the seasonal CO2 jets. Icarus, 2017, 282: 93–103. doi: 10.1016/j.icarus.2016.09.007
    [4]
    Piqueux S, Byrne S, Richardson M I. Sublimation of Mars’s southern seasonal CO2 ice cap and the formation of spiders. Journal of Geophysical Research: Planets, 2003, 108 (E8): 5084. doi: 10.1029/2002je002007
    [5]
    Kieffer H H, Christensen P R, Titus T N. CO2 jets formed by sublimation beneath translucent slab ice in Mars’ seasonal south polar ice cap. Nature, 2006, 442 (7104): 793–796. doi: 10.1038/nature04945
    [6]
    Kieffer H H, Titus T N, Mullins K F, et al. Mars south polar spring and summer behavior observed by TES: Seasonal cap evolution controlled by frost grain size. Journal of Geophysical Research: Planets, 2000, 105 (E4): 9653–9699. doi: 10.1029/1999je001136
    [7]
    Hao J, Michael G G, Adeli S, et al. Variability of spider spatial configuration at the Martian south pole. Planetary and Space Science, 2020, 185: 104848. doi: 10.1016/j.pss.2020.104848
    [8]
    Piqueux S, Christensen P R. North and south subice gas flow and venting of the seasonal caps of Mars: A major geomorphological agent. Journal of Geophysical Research: Planets, 2008, 113 (E6): E06005. doi: 10.1029/2007je003009
    [9]
    Schwamb M E, Aye K-M, Portyankina G, et al. Planet Four: Terrains–Discovery of araneiforms outside of the South Polar layered deposits. Icarus, 2018, 308: 148–187. doi: 10.1016/j.icarus.2017.06.017
    [10]
    Mc Keown L E, Diniega S, Bourke M C, et al. Morphometric trends and implications for the formation of araneiform clusters. Earth and Planetary Science Letters, 2023, 607: 118049. doi: 10.1016/j.jpgl.2023.118049
    [11]
    Portyankina G, Hansen C J, Aye K-M. How Martian araneiforms get their shapes: morphological analysis and diffusion-limited aggregation model for polar surface erosion. Icarus, 2020, 342: 113217. doi: 10.1016/j.icarus.2019.02.032
    [12]
    De Villiers S, Nermoen A, Jamtveit B, et al. Formation of Martian araneiforms by gas-driven erosion of granular material. Geophysical Research Letters, 2012, 39 (13): L13204. doi: 10.1029/2012gl052226
    [13]
    Mc Keown L, McElwaine J N, Bourke M C, et al. The formation of araneiforms by carbon dioxide venting and vigorous sublimation dynamics under Martian atmospheric pressure. Scientific Reports, 2021, 11 (1): 6445. doi: 10.1038/s41598-021-82763-7
    [14]
    Masek J G, Turcotte D L. A diffusion-limited aggregation model for the evolution of drainage networks. Earth and Planetary Science Letters, 1993, 119 (3): 379–386. doi: 10.1016/0012-821x(93)90145-y
    [15]
    Dang Y, Xiao L, Xu Y. Polygons. In: Mars on Earth: A Study of the Qaidam Basin. Singapore: World Scientific, 2021: 199–247.
    [16]
    Lai Z, Mischke S, Madsen D. Paleoenvironmental implications of new OSL dates on the formation of the “Shell Bar” in the Qaidam Basin, northeastern Qinghai-Tibetan Plateau. Journal of Paleolimnology, 2014, 51 (2): 197–210. doi: 10.1007/s10933-013-9710-1
    [17]
    Anglés A, Li Y. The western Qaidam Basin as a potential Martian environmental analogue: An overview. Journal of Geophysical Research: Planets, 2017, 122 (5): 856–888. doi: 10.1002/2017je005293
    [18]
    Li J, Li T, Ma Y, et al. Distribution and origin of brine-type Li-Rb mineralization in the Qaidam Basin, NW China. Science China Earth Sciences, 2022, 65 (3): 477–489. doi: 10.1007/s11430-021-9855-6
    [19]
    Xiao L, Wang J, Dang Y, et al. A new terrestrial analogue site for Mars research: The Qaidam Basin, Tibetan Plateau (NW China). Earth-Science Reviews, 2017, 164: 84–101. doi: 10.1016/j.earscirev.2016.11.003
    [20]
    Zhao J, Shi Y, Xiao L. Valleys. In: Mars on Earth: A Study of the Qaidam Basin. Singapore: World Scientific, 2021: 249–273.
    [21]
    Horton R E. Erosional development of streams and their drainage basins; hydrophysical approach to quantitative morphology. Geological Society of America Bulletin, 1945, 56 (3): 275–370. doi: 10.1130/0016-7606(1945)56[275:EDOSAT]2.0.CO;2
    [22]
    Chicco D, Warrens M J, Jurman G. The coefficient of determination R-squared is more informative than SMAPE, MAE, MAPE, MSE and RMSE in regression analysis evaluation. PeerJ Computer Science, 2021, 7: e623. doi: 10.7717/peerj-cs.623
    [23]
    Witten T A, Sander L M. Diffusion-limited aggregation, a kinetic critical phenomenon. Physical Review Letters, 1981, 47 (19): 1400–1403. doi: 10.1103/physrevlett.47.1400
    [24]
    Sui S G, Gong S L, Wang T. Study on Laplace growth and diffusion limited aggregation with material properties. Advanced Materials Research, 2013, 703 (2): 71–74. doi: 10.4028/www.scientific.net/amr.703.71
    [25]
    La Roche H, Fernández J F, Octavio M, et al. Diffusion-limited-aggregation model for Poisson growth. Physical Review A, 1991, 44 (10): R6185–R6188. doi: 10.1103/physreva.44.r6185
    [26]
    Wang S, Ji H, Zhang Y, et al. Research on the model improvement of a DLA fractal river network. IEEE Access, 2020, 8: 100702–100711. doi: 10.1109/access.2020.2997923
    [27]
    Halsey T C. Diffusion-limited aggregation: A model for pattern formation. Physics Today, 2000, 53 (11): 36–41. doi: 10.1063/1.1333284
    [28]
    Prieto-Ballesteros O, Fernández-Remolar D C, Rodríguez-Manfredi J A, et al. Spiders: Water-driven erosive structures in the southern hemisphere of Mars. Astrobiology, 2006, 6 (4): 651–667. doi: 10.1089/ast.2006.6.651
    [29]
    Boynton W V, Feldman W C, Squyres S W, et al. Distribution of hydrogen in the near surface of Mars: Evidence for subsurface ice deposits. Science, 2002, 297 (5578): 81–85. doi: 10.1126/science.1073722
    [30]
    Bridges J C, Schwenzer S P. The nakhlite hydrothermal brine on Mars. Earth and Planetary Science Letters, 2012, 359–360: 117–123. doi: 10.1016/j.jpgl.2012.09.044
    [31]
    Rivera-Valentín E G, Gough R V, Chevrier V F, et al. Constraining the potential liquid water environment at Gale Crater, Mars. Journal of Geophysical Research: Planets, 2018, 123 (5): 1156–1167. doi: 10.1002/2018je005558
    [32]
    Cassanelli J P, Head J W. Lava heating and loading of ice sheets on early Mars: Predictions for meltwater generation, groundwater recharge, and resulting landforms. Icarus, 2016, 271: 237–264. doi: 10.1016/j.icarus.2016.02.004
    [33]
    Li C, Zheng Y, Wang X, et al. Layered subsurface in Utopia Basin of Mars revealed by Zhurong rover radar. Nature, 2022, 610 (7931): 308–312. doi: 10.1038/s41586-022-05147-5
    [34]
    Ojha L, Wilhelm M, Murchie S, et al. Spectral evidence for hydrated salts in recurring slope lineae on Mars. Nature Geoscience, 2015, 8 (11): 829–832. doi: 10.1038/ngeo2546
    [35]
    Dundas C M, Bramson A M, Ojhal L, et al. Exposed subsurface ice sheets in the Martian mid-latitudes. Science, 2018, 359 (6372): 199–201. doi: 10.1126/science.aao1619
    [36]
    Carr M H. The fluvial history of Mars. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2012, 370 (1966): 2193–2215. doi: 10.1098/rsta.2011.0500
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