Untitled

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

doi:10.1023/a:1011961725645

Cited by 172 publications

(32 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Whatever their source, Gusev rocks do not plot on the low Al/Si trend defined by martian meteorites (Fig. 6) (19). The high Al contents of Gusev basalts could reflect melting of an ancient, relatively undepleted mantle (16), but low contents of incompatible K and P and the presence of normative olivine plus hypersthene suggest a depleted mantle source.…”

Section: S P I R I T a T G U S E V C R A T E Rmentioning

confidence: 94%

Basaltic Rocks Analyzed by the Spirit Rover in Gusev Crater

McSween¹

2004

Science

View full text Add to dashboard Cite

The Spirit landing site in Gusev Crater on Mars contains dark, fine-grained, vesicular rocks interpreted as lavas. Pancam and Mini-Thermal Emission Spectrometer (Mini-TES) spectra suggest that all of these rocks are similar but have variable coatings and dust mantles. Magnified images of brushed and abraded rock surfaces show alteration rinds and veins. Rock interiors contain Յ25% megacrysts. Chemical analyses of rocks by the Alpha Particle X-ray Spectrometer are consistent with picritic basalts, containing normative olivine, pyroxenes, plagioclase, and accessory FeTi oxides. Mössbauer, Pancam, and Mini-TES spectra confirm the presence of olivine, magnetite, and probably pyroxene. These basalts extend the known range of rock compositions composing the martian crust.Rocks at the Spirit landing site are finegrained with irregular vesicles and vugs, suggesting a volcanic origin. The rocks are angular and strewn across the surface, which suggests they were ejected from nearby Bonneville crater (1) by an impact event (2).Pancam and Mini-Thermal Emission Spectrometer (Mini-TES) spectra of rock surfaces indicate two end members, represented by dark-and light-toned rocks, with most rocks falling between these extremes. Three representative rocks, Adirondack, Humphrey, and Mazatzal, located several hundred meters apart, have been analyzed with the Athena instruments (3). Pancam images (4) show that Adirondack and Humphrey are partly coated and that Mazatzal is uniformly coated by light-toned material (Plates 9A, 10A, and 11A). Pancam spectra (Fig. 1) of the dark portions of Adirondack and Humphrey are consistent with the presence of olivine, which has a broad (composite) absorption band near 1000 nm. A weak band center near 930 nm suggests the presence of pyroxene or contamination by ferric oxides.The long-wavelength portion of Mini-TES spectra of dark rock surfaces resembles the Mars Global Surveyor (MGS)-TES spectra of

show abstract

Section: S P I R I T a T G U S E V C R A T E Rmentioning

confidence: 94%

Basaltic Rocks Analyzed by the Spirit Rover in Gusev Crater

McSween¹

2004

Science

View full text Add to dashboard Cite

show abstract

“…Model (1), 'Dry Homogenous' or DH, is the simplest case and was constructed to allow comparison of results with previous publications. It contains a spatially homogenous 2.8 g/cm 3 block of regolith, devoid of water, and with an elemental composition taken as the mean of Pathfinder analyses of soil samples [Wänke et al, 2001]. Model (2), 'Pure Ice' or PI, is a 1 g/cm 3 block of pure water ice used to emulate environments such as the north polar ice cap, frozen crater lakes or the putative Cerberus pack-ice [Murray et al, 2005].…”

Section: Methodsmentioning

confidence: 99%

“…This layering reproduces the model of subsurface permafrost in Arabia Terra based on neutron backscatter data [Mitrofanov et al, 2004], but is also a good approximation of ice-laden regolith in high latitudes. The elemental compositions of topsoil and regolith strata were taken as the Pathfinder average soil and calculated soil-free rock [Wänke et al, 2001] respectively, although previous studies have found the exact elemental composition to have negligible effect on the shielding properties of regolith [Kim et al, 1998]. These scenarios were chosen for this present study, but the model can be rapidly reconfigured to simulate any atmospheric condition or surface composition, as well as deflection through magnetic fields such as the crustal anomalies.…”

Section: Methodsmentioning

confidence: 99%

Modelling the surface and subsurface Martian radiation environment: Implications for astrobiology

Dartnell

Desorgher

Ward

et al. 2007

Geophysical Research Letters

240

226

View full text Add to dashboard Cite

[1] The damaging effect of ionising radiation on cellular structure is one of the prime limiting factors on the survival of life in potential astrobiological habitats. Here we model the propagation of solar energetic protons and galactic cosmic ray particles through the Martian atmosphere and three different surface scenarios: dry regolith, water ice, and regolith with layered permafrost. Particle energy spectra and absorbed radiation dose are determined for the surface and at regular depths underground, allowing the calculation of microbial survival times. Bacteria or spores held dormant by freezing conditions cannot metabolise and become inactivated by accumulating radiation damage. We find that at 2 m depth, the reach of the ExoMars drill, a population of radioresistant cells would need to have reanimated within the last 450,000 years to still be viable. Recovery of viable cells cryopreserved within the putative Cerberus pack-ice requires a drill depth of at least 7.5 m.

show abstract

“…Before the Mars Science Laboratory mission, the bulk chemical composition of the soil was characterized in situ at five different locations on Mars by Viking 1 and 2 (16,17), Mars Pathfinder (18), and the Mars Exploration Rovers (MERs) both at Meridiani Planum (19) and in Gusev Crater (20). Both bright dust and dark soil deposits on opposite sides of the planet were found to be very similar (21).…”

Section: Soil Diversity and Hydration As Observed By Chemcam At Gale mentioning

confidence: 99%

Soil Diversity and Hydration as Observed by ChemCam at Gale Crater, Mars

Meslin

Gasnault

Forni

et al. 2013

Science

221

200

View full text Add to dashboard Cite

International audienceThe ChemCam instrument, which provides insight into martian soil chemistry at the submillimeter scale, identified two principal soil types along the Curiosity rover traverse: a fine-grained mafic type and a locally derived, coarse-grained felsic type. The mafic soil component is representative of widespread martian soils and is similar in composition to the martian dust. It possesses a ubiquitous hydrogen signature in ChemCam spectra, corresponding to the hydration of the amorphous phases found in the soil by the CheMin instrument. This hydration likely accounts for an important fraction of the global hydration of the surface seen by previous orbital measurements. ChemCam analyses did not reveal any significant exchange of water vapor between the regolith and the atmosphere. These observations provide constraints on the nature of the amorphous phases and their hydration

show abstract

Untitled

Cited by 172 publications

References 0 publications

Basaltic Rocks Analyzed by the Spirit Rover in Gusev Crater

Basaltic Rocks Analyzed by the Spirit Rover in Gusev Crater

Modelling the surface and subsurface Martian radiation environment: Implications for astrobiology

Soil Diversity and Hydration as Observed by ChemCam at Gale Crater, Mars

Contact Info

Product

Resources

About