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Volcanogenic fluvial-lacustrine environments in iceland and their utility for identifying past habitability on Mars.

Cousins C - Life (Basel) (2015)

Bottom Line: The availability of liquid water coupled with the potential longevity of such systems renders these localities prime targets for the future exploration of Martian biosignatures.This meltwater can be stored to create subglacial, englacial, and proglacial lakes, or be released as catastrophic floods and proglacial fluvial systems.Sedimentary deposits produced by the resulting fluvial-lacustrine activity are extensive, with lithologies dominated by basaltic minerals, low-temperature alteration assemblages (e.g., smectite clays, calcite), and amorphous, poorly crystalline phases (basaltic glass, palagonite, nanophase iron oxides).

View Article: PubMed Central - PubMed

Affiliation: UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, UK. c.cousins@ed.ac.uk.

ABSTRACT
The search for once-habitable locations on Mars is increasingly focused on environments dominated by fluvial and lacustrine processes, such as those investigated by the Mars Science Laboratory Curiosity rover. The availability of liquid water coupled with the potential longevity of such systems renders these localities prime targets for the future exploration of Martian biosignatures. Fluvial-lacustrine environments associated with basaltic volcanism are highly relevant to Mars, but their terrestrial counterparts have been largely overlooked as a field analogue. Such environments are common in Iceland, where basaltic volcanism interacts with glacial ice and surface snow to produce large volumes of meltwater within an otherwise cold and dry environment. This meltwater can be stored to create subglacial, englacial, and proglacial lakes, or be released as catastrophic floods and proglacial fluvial systems. Sedimentary deposits produced by the resulting fluvial-lacustrine activity are extensive, with lithologies dominated by basaltic minerals, low-temperature alteration assemblages (e.g., smectite clays, calcite), and amorphous, poorly crystalline phases (basaltic glass, palagonite, nanophase iron oxides). This paper reviews examples of these environments, including their sedimentary deposits and microbiology, within the context of utilising these localities for future Mars analogue studies and instrument testing.

No MeSH data available.


Related in: MedlinePlus

(A) Map of Iceland showing the location of the sites covered in this paper. The active north, east, and western neovolcanic zones are shown (yellow), as well as ice cover (white); (B) Corresponding National Land Survey of Iceland (NLSI) infrared satellite image of Iceland (IS 50V database/SPOT data), showing the lack of vegetation cover (red) within the neovolcanic zones.
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life-05-00568-f002: (A) Map of Iceland showing the location of the sites covered in this paper. The active north, east, and western neovolcanic zones are shown (yellow), as well as ice cover (white); (B) Corresponding National Land Survey of Iceland (NLSI) infrared satellite image of Iceland (IS 50V database/SPOT data), showing the lack of vegetation cover (red) within the neovolcanic zones.

Mentions: Due to the sub-arctic location of Iceland many parts of the country lie within glacial-periglacial-semi-arid climates, with annual precipitation as low as 400 mm in the interior [38]. As such, an estimated 60% of Icelandic glaciers overlie active volcanic systems [38]. This interaction between active volcanism along the neovolcanic zone and surface ice over the past 0.8 Ma [34] has resulted in widespread volcaniclastic sedimentation, including ubiquitous hyaloclastite/hyalotuff sequences, volcanogenic fluvial and lacustrine environments, and crustal hydrothermal alteration (both low and high temperature). Furthermore, many deposits and ongoing active environments are relatively undisturbed or reworked by vegetation, fauna, or human influence, particularly along the active rift zone (Figure 2B). Moreover, these regions are also specific analogues for putative glaciovolcanic landforms on Mars (e.g., [39]), which may represent one of the few habitable environments that could have pervaded into the Amazonian [39,40]. For more detail on the habitability of such glaciovolcanic habitats, the reader is referred to [41,42]. Iceland is a well-known locality for Mars analogue research, including aqueous alteration of basaltic crust [43] and gully formation [44]. Volcaniclastic sedimentary terrains and the fluvial-lacustrine processes that modify them have been largely overlooked, although comparisons have been made previously between subglacial outflow events (“jökulhlaups”) and flood channels on Mars [45], and a study by [46] demonstrated the utility of low temperature alteration phases within Icelandic basaltic outwash sediments as a good analogue for detecting similar assemblages on Mars. This paper provides a synthesis of example sedimentary fluvial-lacustrine terrains and contemporary active lacustrine environments in Iceland, with the view to present these as new and currently underused analogues for similar habitats and deposits on Mars, particularly with relevance to habitability and biosignature detection. As such, the aim of this paper is not to provide a direct geomorphological or formational analogue to specific terrains on Mars, but to expand the current variety of terrestrial localities which are of benefit to ongoing and future robotic exploration of Mars.


Volcanogenic fluvial-lacustrine environments in iceland and their utility for identifying past habitability on Mars.

Cousins C - Life (Basel) (2015)

(A) Map of Iceland showing the location of the sites covered in this paper. The active north, east, and western neovolcanic zones are shown (yellow), as well as ice cover (white); (B) Corresponding National Land Survey of Iceland (NLSI) infrared satellite image of Iceland (IS 50V database/SPOT data), showing the lack of vegetation cover (red) within the neovolcanic zones.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4390869&req=5

life-05-00568-f002: (A) Map of Iceland showing the location of the sites covered in this paper. The active north, east, and western neovolcanic zones are shown (yellow), as well as ice cover (white); (B) Corresponding National Land Survey of Iceland (NLSI) infrared satellite image of Iceland (IS 50V database/SPOT data), showing the lack of vegetation cover (red) within the neovolcanic zones.
Mentions: Due to the sub-arctic location of Iceland many parts of the country lie within glacial-periglacial-semi-arid climates, with annual precipitation as low as 400 mm in the interior [38]. As such, an estimated 60% of Icelandic glaciers overlie active volcanic systems [38]. This interaction between active volcanism along the neovolcanic zone and surface ice over the past 0.8 Ma [34] has resulted in widespread volcaniclastic sedimentation, including ubiquitous hyaloclastite/hyalotuff sequences, volcanogenic fluvial and lacustrine environments, and crustal hydrothermal alteration (both low and high temperature). Furthermore, many deposits and ongoing active environments are relatively undisturbed or reworked by vegetation, fauna, or human influence, particularly along the active rift zone (Figure 2B). Moreover, these regions are also specific analogues for putative glaciovolcanic landforms on Mars (e.g., [39]), which may represent one of the few habitable environments that could have pervaded into the Amazonian [39,40]. For more detail on the habitability of such glaciovolcanic habitats, the reader is referred to [41,42]. Iceland is a well-known locality for Mars analogue research, including aqueous alteration of basaltic crust [43] and gully formation [44]. Volcaniclastic sedimentary terrains and the fluvial-lacustrine processes that modify them have been largely overlooked, although comparisons have been made previously between subglacial outflow events (“jökulhlaups”) and flood channels on Mars [45], and a study by [46] demonstrated the utility of low temperature alteration phases within Icelandic basaltic outwash sediments as a good analogue for detecting similar assemblages on Mars. This paper provides a synthesis of example sedimentary fluvial-lacustrine terrains and contemporary active lacustrine environments in Iceland, with the view to present these as new and currently underused analogues for similar habitats and deposits on Mars, particularly with relevance to habitability and biosignature detection. As such, the aim of this paper is not to provide a direct geomorphological or formational analogue to specific terrains on Mars, but to expand the current variety of terrestrial localities which are of benefit to ongoing and future robotic exploration of Mars.

Bottom Line: The availability of liquid water coupled with the potential longevity of such systems renders these localities prime targets for the future exploration of Martian biosignatures.This meltwater can be stored to create subglacial, englacial, and proglacial lakes, or be released as catastrophic floods and proglacial fluvial systems.Sedimentary deposits produced by the resulting fluvial-lacustrine activity are extensive, with lithologies dominated by basaltic minerals, low-temperature alteration assemblages (e.g., smectite clays, calcite), and amorphous, poorly crystalline phases (basaltic glass, palagonite, nanophase iron oxides).

View Article: PubMed Central - PubMed

Affiliation: UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, UK. c.cousins@ed.ac.uk.

ABSTRACT
The search for once-habitable locations on Mars is increasingly focused on environments dominated by fluvial and lacustrine processes, such as those investigated by the Mars Science Laboratory Curiosity rover. The availability of liquid water coupled with the potential longevity of such systems renders these localities prime targets for the future exploration of Martian biosignatures. Fluvial-lacustrine environments associated with basaltic volcanism are highly relevant to Mars, but their terrestrial counterparts have been largely overlooked as a field analogue. Such environments are common in Iceland, where basaltic volcanism interacts with glacial ice and surface snow to produce large volumes of meltwater within an otherwise cold and dry environment. This meltwater can be stored to create subglacial, englacial, and proglacial lakes, or be released as catastrophic floods and proglacial fluvial systems. Sedimentary deposits produced by the resulting fluvial-lacustrine activity are extensive, with lithologies dominated by basaltic minerals, low-temperature alteration assemblages (e.g., smectite clays, calcite), and amorphous, poorly crystalline phases (basaltic glass, palagonite, nanophase iron oxides). This paper reviews examples of these environments, including their sedimentary deposits and microbiology, within the context of utilising these localities for future Mars analogue studies and instrument testing.

No MeSH data available.


Related in: MedlinePlus