Thermodynamic Constrains on Smectite and Iron Oxide Formation at Gale Crater, Mars: Insights into Potential Free Energy from Aerobic Fe Oxidation in Lake Water–Groundwater Mixing Zone

The presence of saponite and iron oxides in Sheepbed mudstone of Yellowknife Bay at Gale crater on Mars is considered as evidence of a habitable fluvio-lacustrine environment for chemolithoautotrophy. However, the energetic availability for metabolic reactions is poorly constrained. Herein, we propose the possible mixing of surface water and groundwater that (i) explains the formation of magnetite and hematite detected in Sheepbed mudstone and (ii) may work as a potential habitable zone for aerobic Fe2+-oxidizing microbes. Our thermodynamic modeling of water–rock reactions revealed that the formation of abundant saponite in Sheepbed mudstone may occur under various conditions of water-to-rock mass ratios, temperatures (5–200 °C), and initial fluid compositions. In contrast, the formation of iron oxides in the mudstone can be explained only by the mixing of Fe2+-rich groundwater and more oxidized surface waters, where the Fe2+-rich groundwater can be generated by the low-temperature water–rock reactions with a CO2-bearing initial fluid. The calculated bioavailable energy of aerobic Fe2+ oxidation in the fluid-mixing zone on Mars is similar to that estimated for a fluid-mixing zone on Earth actually inhabited by aerobic Fe2+-oxidizing microbes. The findings will contribute to a better understanding of potential habitability on Mars.

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Semiarid climate and hyposaline lake on early Mars inferred from reconstructed water chemistry at Gale

Nature Communications ◽

10.1038/s41467-019-12871-6 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 8

Author(s):

Keisuke Fukushi ◽

Yasuhito Sekine ◽

Hiroshi Sakuma ◽

Koki Morida ◽

Robin Wordsworth

Keyword(s):

Pore Water ◽

Surface Waters ◽

Natural Waters ◽

Lacustrine Sediments ◽

Redox States ◽

Gale Crater ◽

Fundamental Properties ◽

Formation Conditions ◽

Early Mars ◽

Multiple Scenarios

Abstract Salinity, pH, and redox states are fundamental properties that characterize natural waters. These properties of surface waters on early Mars reflect palaeoenvironments, and thus provide clues on the palaeoclimate and habitability. Here we constrain these properties of pore water within lacustrine sediments of Gale Crater, Mars, using smectite interlayer compositions. Regardless of formation conditions of smectite, the pore water that last interacted with the sediments was of Na-Cl type with mild salinity (~0.1–0.5 mol/kg) and circumneutral pH. To interpret this, multiple scenarios for post-depositional alterations are considered. The estimated Na-Cl concentrations would reflect hyposaline, early lakes developed in 104–106-year-long semiarid climates. Assuming that post-depositional sulfate-rich fluids interacted with the sediments, the redox disequilibria in secondary minerals suggest infiltration of oxidizing fluids into reducing sediments. Assuming no interactions, the redox disequilibria could have been generated by interactions of upwelling groundwater with oxidized sediments in early post-depositional stages.

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A Habitable Fluvio-Lacustrine Environment at Yellowknife Bay, Gale Crater, Mars

Science ◽

10.1126/science.1242777 ◽

2013 ◽

Vol 343 (6169) ◽

pp. 1242777-1242777 ◽

Cited By ~ 442

Author(s):

J. P. Grotzinger ◽

D. Y. Sumner ◽

L. C. Kah ◽

K. Stack ◽

S. Gupta ◽

...

Keyword(s):

Lacustrine Environment ◽

Gale Crater

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The Registration of the Mid-Paleocene Biotic Event (MPBE) in Tunisia

Paleontology Journal ◽

10.1155/2014/760436 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Narjess Karoui-Yaakoub ◽

Moncef Saïd Mtimet ◽

Mohamed Hédi Negra ◽

Chaima Grira ◽

Wafa Gusemi

Keyword(s):

Iron Oxides ◽

Deep Water ◽

Surface Waters ◽

Benthic Foraminifera ◽

Rare Species ◽

Planktonic Foraminifera ◽

Dissolution Process ◽

Dissolution Tests ◽

First Time ◽

El Haria Formation

In Tunisia, the Paleocene biomarkers are identified within the El Haria Formation shales. The Selandian is absent in most of the Paleocene outcrops and the Thanetian is unconformable to different stages of the Cretaceous. In the middle of Selandian, with the beginning of the Globanomalina pseudomenardii (P4) zone, we note that the assemblage of planktonic foraminifera becomes very poorly preserved and much less abundant than at the base. It is represented by rare species and there has been a start of the microfauna dissolution tests and an enrichment in iron oxides, silica, and gypsum crystals. The dissolution process is increasing more and more and a drop in the content of carbonates is clearly recorded at the top of Selandian. However, we note that some small benthic foraminifera belonging to the genera Lenticulina and Anomalina escape the dissolution and very few planktonic foraminifera belonging to the genera Subbotina are preserved. This dramatic and abnormal dissolution extends over a considerable thickness. These features could be an expression of the mid-Paleocene biotic event (MPBE), registered for the first time in Tunisia. This intense dissolution is caused probably by the change in the solubility of carbonates, which may be related to the changes in the deep-water circulation or to the change in the productivity of the surface waters.

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Carbon dioxide drawdown by Devonian lavas

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s1755691014000152 ◽

2014 ◽

Vol 105 (1) ◽

pp. 1-8

Author(s):

John Parnell ◽

Kirsty Macleod ◽

Malcolm J. Hole

Keyword(s):

Carbon Dioxide ◽

Iron Oxides ◽

Surface Waters ◽

Volcanic Activity ◽

Lower Devonian ◽

Volcanic Rocks ◽

High Capacity ◽

Time Frame ◽

Data Set ◽

Geological Record

ABSTRACTLower Devonian volcanic rocks in the northern British Isles, especially Scotland, show extensive evidence for contemporaneous subaerial weathering. Basalt and andesite lavas were altered to red iron oxides, commonly accompanied by calcite. Measurement of carbonate contents in 104 samples over a region of 100,000 km2 show an average of 13% calcite. Weighted for outcrop thickness, this represents an estimated 7.3×1016 moles CO2, extracted from surface waters and ultimately the atmosphere. The time frame for this drawdown is difficult to constrain, but complete weathering of a one-metre unit over 1000 years would involve CO2 consumption comparable with the highest rates determined in modern basaltic watersheds. These data demonstrate that volcanic activity can be a major sink, as well as a source for CO2, and provide a data set for modelling of CO2 flux during episodes of volcanic activity in the geological record. The high capacity of the Devonian lavas for CO2 drawdown emphasises the potential of basalts for CO2 sequestration.

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Theoretical methods for the determination of mixing

Laser and Particle Beams ◽

10.1017/s0263034603213227 ◽

2003 ◽

Vol 21 (3) ◽

pp. 429-436 ◽

Cited By ~ 3

Author(s):

BAOLIAN CHENG ◽

JAMES GLIMM ◽

HYEONSEONG JIN ◽

DAVID SHARP

Keyword(s):

Experimental Data ◽

Point Of View ◽

Fluid Mixing ◽

Considerable Progress ◽

Theoretical Point ◽

Mixing Zone ◽

Theoretical Methods ◽

Two Phases ◽

Atomic Mixing

Acceleration-driven fluid mixing is studied here from a theoretical point of view. Considerable progress has been achieved in the understanding of mix. Theories of the authors are reviewed that allow prediction of the edge of the mixing zone, in agreement with experimental data. Theories that describe the distribution of masses within the mixing region are also reviewed. The theory we present describes a chunk mix regime, in which two phases are mixed at a chunk level, but for which there is no atomic mixing. Thus the two phases are segregated into disjoint regions of space.

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Intense subaerial weathering of eolian sediments in Gale crater, Mars

Science Advances ◽

10.1126/sciadv.abh2687 ◽

2021 ◽

Vol 7 (32) ◽

pp. eabh2687

Author(s):

Jiacheng Liu ◽

Joseph R. Michalski ◽

Mei-Fu Zhou

Keyword(s):

Environmental Change ◽

Ancient Lake ◽

Acidic Precipitation ◽

Lacustrine Environment ◽

Gale Crater ◽

Stratigraphic Section ◽

Eolian Sediments ◽

Curiosity Rover

After over 8 years of successful surface operations on Mars, the Curiosity rover has revealed much about the environment in Gale crater. Despite early observations of a lacustrine environment, few of the subsequent deposits exhibit demonstrable lacustrine character. We suggest instead that most of the stratigraphic section explored to date can be best explained as eolian and/or volcaniclastic sediments subaerially chemically weathered by acidic precipitation in a reduced atmosphere. Most of the deposits in Gale crater seemingly did not form in an ancient lake, but the results nonetheless shed considerable light on ancient climate, environmental change, and the astrobiology of Mars. Discoveries by Curiosity provide a critical piece to Mars’ global alteration puzzle.

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The removal of colloidal lead during estuarine mixing: seasonal variations and importance of iron oxides and humic substances

Marine and Freshwater Research ◽

10.1071/mf10220 ◽

2011 ◽

Vol 62 (4) ◽

pp. 329 ◽

Cited By ~ 10

Author(s):

Virginie Tanguy ◽

Matthieu Waeles ◽

Julien Gigault ◽

Jean-Yves Cabon ◽

François Quentel ◽

...

Keyword(s):

Humic Substances ◽

Iron Oxides ◽

Seasonal Variations ◽

Salinity Range ◽

Mixing Zone ◽

Size Fractions ◽

Estuarine Mixing ◽

Colloidal Lead ◽

Insight Into ◽

Organomineral Complexes

In the present study, seven colloidal fractions of lead (Pb) were analysed along the mixing zone of the Penzé estuary over the Year 2009, with the aim to provide some insight into the mechanism that removes the metal from the <0.45-µm fraction. According to our results, Pb was generally found as large colloids (>300 kDa) and was removed in the salinity range 0–10 from all of the size fractions where it was significantly found. Because the colloidal fractionation of Pb was strongly linked to that of iron (Fe) and humic substances (HS), the removal of Pb in the mixing area must occur under flocculation of organomineral complexes. A key period corresponding to the first strong autumnal precipitations was also revealed in the present work. At this time of the year, the mobilisation of Pb (and Fe) from catchment soils is enhanced by the mobilisation of HS and the metal is associated with smaller colloids (30–300 kDa).

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Seasonality and sunlight dependency of manganese oxide formation and cycling in surface waters of a meromictic pond

10.7185/gold2021.4804 ◽

2021 ◽

Author(s):

Hayley Gadol ◽

Chadlin Ostrander ◽

Lina Taenzer ◽

Veronique Oldham ◽

Luciana Villarroel ◽

...

Keyword(s):

Manganese Oxide ◽

Surface Waters ◽

Oxide Formation

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Microbial habitability of the early Mars lacustrine environment sustained by iron redox cycling

10.1101/2021.09.07.459191 ◽

2021 ◽

Author(s):

Rachel A. Moore ◽

Christopher E. Carr

Keyword(s):

Solid Phase ◽

Modeling Processes ◽

Chemical Components ◽

Metabolic Potential ◽

Lacustrine Environment ◽

Gale Crater ◽

The Past ◽

Lack Of Information ◽

Early Mars ◽

Iron Redox

AbstractSeveral studies have reported new data on the estimated compositions of chemical components at Gale crater; however, there is still a lack of information regarding potential past support of biomass and detectable biomarkers of ancient life. In this study we evaluate microbial habitability of early Mars constrained by the recently reconstructed water chemistry at Gale. The modeled community is based on Fe-metabolizing bacteria with the ability to utilize solid-phase iron oxides (e.g., magnetite) as an electron source or sink. Our results illustrate the plausibility of a sustained community in Gale Lake and provides suggestions for future modeled and laboratory-based studies to further evaluate the past habitability of Mars, biosignatures and their preservation potential, and hidden metabolic potential.One Sentence SummaryThis work provides an existence proof of habitability on early Mars and demonstrates modeling processes by which the habitability of extraterrestrial environments can be explored quantitatively.

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