Chemical Composition of Rocks and Soils at the Pathfinder Site

Wänke, H.; Brückner, J.; Dreibus, G.; Rieder, R.; Ryabchikov, I. D.

doi:10.1007/978-94-017-1035-0_11

Cited by 107 publications

(165 citation statements)

References 22 publications

Supporting

Mentioning

153

Contrasting

Order By: Relevance

“…If all of the oxygen detected by SAM resulted from perchlorate decomposition, the estimated ClO 4 -abundance in the Rocknest <150-mm fraction (Table 2) would be comparable to the abundances observed by Phoenix. This abundance does not account for all of the chlorine detected by Curiosity's Alpha Particle X-ray Spectrometer (APXS) (14), implying the presence of other chlorinebearing species at Rocknest.…”

Section: Volatile Releasementioning

confidence: 62%

“…Surface deposits, including aeolian fines, form an important record of these material exchanges. Martian surface fines are especially interesting because previous chemical studies by the Viking landers, Pathfinder, Spirit, and Opportunity (1)(2)(3)(4) show that the bulk chemical composition of these materials is relatively constant at widely spaced locations across the planet. This can result from a combination of mechanical mixing on global scales and a similarity in the chemical composition of bedrock and sediments on regional to global scales (5).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Volatile, Isotope, and Organic Analysis of Martian Fines with the Mars Curiosity Rover

Leshin

Mahaffy

Webster

et al. 2013

Science

384

411

View full text Add to dashboard Cite

International audienceSamples from the Rocknest aeolian deposit were heated to ~835°C under helium flow and evolved gases analyzed by Curiosity's Sample Analysis at Mars instrument suite. H2O, SO2, CO2, and O2 were the major gases released. Water abundance (1.5 to 3 weight percent) and release temperature suggest that H2O is bound within an amorphous component of the sample. Decomposition of fine-grained Fe or Mg carbonate is the likely source of much of the evolved CO2. Evolved O2 is coincident with the release of Cl, suggesting that oxygen is produced from thermal decomposition of an oxychloride compound. Elevated δD values are consistent with recent atmospheric exchange. Carbon isotopes indicate multiple carbon sources in the fines. Several simple organic compounds were detected, but they are not definitively martian in origin

show abstract

Section: Volatile Releasementioning

confidence: 62%

mentioning

confidence: 99%

Volatile, Isotope, and Organic Analysis of Martian Fines with the Mars Curiosity Rover

Leshin

Mahaffy

Webster

et al. 2013

Science

384

411

View full text Add to dashboard Cite

show abstract

“…This partly cemented "soil" is believed to have a fairly homogeneous composition across the planet as a result of redistribution by aeolian activity. Viking and Pathfinder soils have a similar basaltic nature, although the former have higher SO 3 and Cl contents (Newsom et al, 1999;Wänke et al, 2001). The basaltic silicate composition is similar to that of the shergottites.…”

Section: Relationship Of Snc Secondary Assemblages To Current Martianmentioning

confidence: 84%

Alteration Assemblages in Martian Meteorites: Implications for Near-Surface Processes

Bridges

Catling

Saxton

et al. 2001

Space Sciences Series of ISSI

128

201

View full text Add to dashboard Cite

Abstract. The SNC (Shergotty-Nakhla-Chassigny) meteorites have recorded interactions between martian crustal fluids and the parent igneous rocks. The resultant secondary minerals -which comprise up to ~ 1 vol.% of the meteorites -provide information about the timing and nature of hydrous activity and atmospheric processes on Mars. We suggest that the most plausible models for secondary mineral formation involve the evaporation of low temperature o C) brines. This is consistent with the simple mineralogy of these assemblages -Fe-Mg-Ca carbonates, anhydrite, gypsum, halite, clays -and the chemical fractionation of Ca-to Mg-rich carbonate in ALH84001 'rosettes'. Longer-lived, and higher temperature, hydrothermal systems would have caused more silicate alteration than is seen and probably more complex mineral assemblages. Experimental and phase equilibria data on carbonate compositions similar to those present in the SNCs imply low temperatures of formation with cooling taking place over a short period of time (e.g. days). The ALH84001 carbonate also probably shows the effects of partial vapourisation and dehydration related to an impact event postdating the initial precipitation. This shock event may have led to the formation of sulphide and some magnetite in the Fe-rich outer parts of the rosettes.Radiometric dating (K-Ar, Rb-Sr) of the secondary mineral assemblages in one of the nakhlites (Lafayette) suggests that they formed between 0 and 670 Ma, and certainly long after the crystallisation of the host igneous rocks. Crystallisation of ALH84001 carbonate took place 0.5 Ga after the parent rock. These age ranges and the other research on these assemblages suggest that environmental conditions conducive to near-surface liquid water have been present on Mars periodically over the last ~1 Ga. This fluid activity cannot have been continuous over geological time because in that case much more silicate alteration would have taken place in the meteorite parent rocks and the soluble salts would probably not have been preserved.The secondary minerals could have been precipitated from brines with seawater-like composition, high bicarbonate contents and a weakly acidic nature. The co-existence of siderite (Fe-carbonate) and clays in the nakhlites suggests that the pCO 2 level in equilibrium with the parent brine may have been 50 mbar or more. The brines could have originated as flood waters which percolated through the top few hundred metres of the crust, releasing cations from the surrounding parent rocks. There is no spectroscopic or photographic evidence for extensive evaporite deposits on the current martian surface but some salt precipitation through solute concentration must have occurred as floodwaters associated with many of the martian channels ponded in low-lying areas. The high sulphur and chlorine concentrations of the martian soil have most likely resulted from aeolian redistribution of such aqueously-deposited salts and from reaction of the martian surface with volcanic acid volatiles. However, the SNC salt a...

show abstract

“…We also compare the Gusev mantle source with that of the younger shergottites and investigate how mantle heterogeneities may have evolved over the history of the planet. Other geochemical data sets for Martian crustal rocks that were analyzed by the Pathfinder mission (Wänke et al, 2001;Foley et al, 2003), the Gamma-Ray Spectrometer (GRS) on the Mars Odyssey orbiter (Boynton et al, 2007) or indirectly by Thermal Emission Spectrometer (TES) on the Mars Global Surveyor orbiter Hamilton et al, 2001) indicate widespread surface alteration, sediment redistribution, and (or) dust contamination and are not considered for this study. We also do not consider the nakhlites (clinopyroxenites) or chassignites (dunites) because they have cumulate textures and the compositions of their parental magmas are a source of debate (e.g., Goodrich et al, 2010;Treiman, 2005).…”

Section: Introductionmentioning

confidence: 99%

The evolution of a heterogeneous Martian mantle: Clues from K, P, Ti, Cr, and Ni variations in Gusev basalts and shergottite meteorites

Schmidt

McCoy

2010

Earth and Planetary Science Letters

View full text Add to dashboard Cite

Chemical Composition of Rocks and Soils at the Pathfinder Site

Cited by 107 publications

References 22 publications

Volatile, Isotope, and Organic Analysis of Martian Fines with the Mars Curiosity Rover

Volatile, Isotope, and Organic Analysis of Martian Fines with the Mars Curiosity Rover

Alteration Assemblages in Martian Meteorites: Implications for Near-Surface Processes

The evolution of a heterogeneous Martian mantle: Clues from K, P, Ti, Cr, and Ni variations in Gusev basalts and shergottite meteorites

Contact Info

Product

Resources

About