Reproducing early Martian atmospheric carbon dioxide partial pressure by modeling the formation of Mg‐Fe‐Ca carbonate identified in the Comanche rock outcrops on Mars

Berk, Wolfgang van; Fu, Yunjiao; Ilger, Jan-Michael

doi:10.1029/2012je004173

Cited by 18 publications

(13 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A moderately dense atmosphere at ~4 Ga has also been suggested by other geochemical, geological, and theoretical constraints (Manga et al 2012;Van Berk et al 2012;Cessata et al 2012;Kite et al 2014;Forget et al 2013;Hu et al 2015). Constraints on the atmospheric pressure on early Mars are summarized in Figure 16.…”

Section: The Evolution Of the Atmospheric Pressure Through Timementioning

confidence: 65%

A lower limit of atmospheric pressure on early Mars inferred from nitrogen and argon isotopic compositions

Kurokawa

Kurosawa

Usui

2018

Icarus

View full text Add to dashboard Cite

We examine the history of the loss and replenishment of the Martian atmosphere using elemental and isotopic compositions of nitrogen and noble gases. The evolution of the atmosphere is calculated by taking into consideration various processes: impact erosion and replenishment by asteroids and comets, atmospheric escape induced by solar radiation and wind, volcanic degassing, and gas deposition by interplanetary dust particles. Our model reproduces the elemental and isotopic compositions of N and noble gases (except for Xe) in the Martian atmosphere, as inferred from exploration missions and analyses of Martian meteorites. Other processes such as ionization-induced fractionation, which are not included in our model, are likely to make a large contribution in producing the current Xe isotope composition. Since intense impacts during the heavy bombardment period greatly affect the atmospheric mass, the atmospheric pressure evolves stochastically. Whereas a dense atmosphere preserves primitive isotopic compositions, a thin atmosphere on early Mars is severely influenced by stochastic impact events and following escape-induced fractionation. The onset of fractionation following the decrease in atmospheric pressure is explained by shorter timescales of isotopic fractionation under a lower atmospheric pressure. The comparison of our numerical results with the less fractionated N ( 15 N/ 14 N) and Ar ( 38 Ar/ 36 Ar) isotope compositions of the ancient atmosphere recorded in the Martian meteorite Allan Hills 84001 provides a lower limit of the atmospheric pressure in 4 Ga to preserve the primitive isotopic compositions. We conclude that the atmospheric pressure was higher than approximately 0.5 bar at 4 Ga.

show abstract

Section: The Evolution Of the Atmospheric Pressure Through Timementioning

confidence: 65%

A lower limit of atmospheric pressure on early Mars inferred from nitrogen and argon isotopic compositions

Kurokawa

Kurosawa

Usui

2018

Icarus

View full text Add to dashboard Cite

show abstract

“…The value of 1 bar for a CO 2rich early Mars is quite arbitrary, essentially because there are not many constraints on the CO 2 pressure of early Mars. Some studies suggested that the pressure on early Mars was quite similar to the present-day value and other processes were helping maintaining liquid water on the surface (Barabash et al, 2007;Chevrier et al, 2007;Fairen et al, 2009;Haberle, 1998;Kasting, 1991), while other atmospheric models suggested higher pressures are needed (Forget et al, 2013;Kurokawa et al, 2018;Manga et al, 2012;Pollack et al, 1987;van Berk et al, 2012). In this last case, the pressure usually ranges from 1 to 10 bars depending on the assumptions in the models (Kite, 2019).…”

Section: Reaction Pathwaysmentioning

confidence: 99%

Carbonate‐Phyllosilicate Parageneses and Environments of Aqueous Alteration in Nili Fossae and Mars

Chevrier¹,

Morisson²

2021

JGR Planets

View full text Add to dashboard Cite

The equilibrium thermodynamics of Fe/Mg-phyllosilicates and carbonates have been investigated using numerical modeling, with emphasis on the effects of evaporation and temperature (hydrothermalism) under conditions related to present-day and primitive Mars, that is, low or high CO 2 partial pressure, under oxidizing or reducing environments. Findings are discussed in relation to alteration and weathering of minerals found in the Nili Fossae region. Results show that nontronite precipitates at very high water-to-precipitate ratio and low temperature, in association with ferrihydrite. During evaporation, this assemblage leads to carbonates: calcite and magnesite, and to low temperature iron-rich serpentine phyllosilicates such as cronstedtite or berthierine under reducing conditions. At high temperature, the initial paragenesis dominated by nontronite leads to hematite and berthierine at low CO 2 partial pressure, and to talc, magnesite and antigorite at high CO 2 partial pressure. Thus, the Fe/Mg-smectites, Mg-carbonate, and Mg-serpentine found near Nili Fossae may result from several alteration events. Weathering of primitive bedrock formed nontronite, with subsequent or concurrent hydrothermalism leading to Mg-serpentine. Further carbonation due to CO 2 -rich fluids led to talc, magnesite and to hydrogen/carbon monoxide/methane in the presence of iron, but at relatively low partial pressures (up to 10 −4 bar). Unless the serpentinization process acted for extended periods of time and over a large portion of the martian surface, it is unlikely it significantly contributed to the atmospheric composition, except maybe for H 2 . However, such water-rich active environments with the presence of redox reactions could have been suitable for the potential emergence of biological activity.Plain Language Summary Multiple locations on Mars exhibit phyllosilicate deposits, which have been used as indicators of temperate paleoenvironments with abundant liquid water. Of these, Nili Fossae is one of the rare occurrences where additional phases such as carbonates or serpentine are found. These minerals also pinpoint to possible hydrothermal activity, which is very important for the putative emergence of biologic activity on the red planet. Our work aims at understanding these various environments using numerical thermodynamic simulations of the mineral assemblages observed in this province. We observe that Mg,Fe-phyllosilicates such as nontronite form in low temperatures environments with very abundant water, and relatively oxidizing conditions (so rather on the surface) while magnesite and serpentine mixtures are characterized by higher temperatures (typically 200-300 °C) in the presence of high CO 2 partial pressures and more reducing conditions. Such hydrothermal reactions should also have led to the formations of hydrogen, carbon monoxide, and perhaps methane, but at concentrations probably too low to allow for global warming on Mars, unless they would have been significantly extended geographically and temporally. Nonethel...

show abstract

“…Mg‐carbonate in nearby outcrops has also been reported from orbit [ Carter and Poulet , ]. The preservation of substantial olivine in these carbonate‐rich rocks was interpreted to implicate hydrothermal alteration at relatively low water activity [ Morris et al ., ], but a lacustrine evaporative origin has also been proposed [ Ruff et al ., ], and geochemical modeling indeed favors low‐temperature (<85°C) formation from an environment (lake or aquifer) open to CO 2 exchange with a ~0.5–2 bar Late Noachian atmosphere over at least ~10 5 years [ Van Berk et al ., ].…”

Section: Introductionmentioning

confidence: 99%

Orbital evidence for more widespread carbonate‐bearing rocks on Mars

et al. 2016

View full text Add to dashboard Cite

Carbonates are key minerals for understanding ancient Martian environments because they are indicators of potentially habitable, neutral-to-alkaline water and may be an important reservoir for paleoatmospheric CO 2 . Previous remote sensing studies have identified mostly Mg-rich carbonates, both in Martian dust and in a Late Noachian rock unit circumferential to the Isidis basin. Here we report evidence for older Fe-and/or Ca-rich carbonates exposed from the subsurface by impact craters and troughs. These carbonates are found in and around the Huygens basin northwest of Hellas, in western Noachis Terra between the Argyre basin and Valles Marineris, and in other isolated locations spread widely across the planet. In all cases they cooccur with or near phyllosilicates, and in Huygens basin specifically they occupy layered rocks exhumed from up to~5 km depth. We discuss factors that might explain their observed regional distribution, arguments for why carbonates may be even more widespread in Noachian materials than presently appreciated and what could be gained by targeting these carbonates for further study with future orbital or landed missions to Mars.

show abstract

Reproducing early Martian atmospheric carbon dioxide partial pressure by modeling the formation of Mg‐Fe‐Ca carbonate identified in the Comanche rock outcrops on Mars

Cited by 18 publications

References 31 publications

A lower limit of atmospheric pressure on early Mars inferred from nitrogen and argon isotopic compositions

A lower limit of atmospheric pressure on early Mars inferred from nitrogen and argon isotopic compositions

Carbonate‐Phyllosilicate Parageneses and Environments of Aqueous Alteration in Nili Fossae and Mars

Orbital evidence for more widespread carbonate‐bearing rocks on Mars

Contact Info

Product

Resources

About