Martian meteorites Research Papers - Academia.edu (original) (raw)

The present study describes Martian ooids formed by Martian microbes. NASA's Mars Rover Curiosity discovered plentiful indigenous spherical ooids at High Dune and Namib Dune in Bagnold dune field, Gale Crater, Mars. The spherical Martian... more

The present study describes Martian ooids formed by Martian microbes. NASA's Mars Rover Curiosity discovered plentiful indigenous spherical ooids at High Dune and Namib Dune in Bagnold dune field, Gale Crater, Mars. The spherical Martian ooids contain nuclei and range from 0.1 mm to 0.5 mm in diameter. Colors of the spherical Martian ooids are various, including white, yellow translucent, green, gray, and yellow. The spherical Martian ooids should have been formed by microbes, because 1) ooids of Earth have recently been found to be formed by microbes and 2) microbial borings are found in ooids of Earth and of Mars. There is no evidence that proves ooids are formed by agitated water.

Mars' Atmosphere from Curiosity The Sample Analysis at Mars (SAM) instrument on the Curiosity rover that landed on Mars in August last year is designed to study the chemical and isotopic composition of the martian atmosphere. Mahaffy... more

Mars' Atmosphere from Curiosity The Sample Analysis at Mars (SAM) instrument on the Curiosity rover that landed on Mars in August last year is designed to study the chemical and isotopic composition of the martian atmosphere. Mahaffy et al. (p. 263 ) present volume-mixing ratios of Mars' five major atmospheric constituents (CO 2 , Ar, N 2 , O 2 , and CO) and isotope measurements of 40 Ar/ 36 Ar and C and O in CO 2 , based on data from one of SAM's instruments, obtained between 31 August and 21 November 2012. Webster et al. (p. 260 ) used data from another of SAM's instruments obtained around the same period to determine isotope ratios of H, C, and O in atmospheric CO 2 and H 2 O. Agreement between the isotopic ratios measured by SAM with those of martian meteorites, measured in laboratories on Earth, confirms the origin of these meteorites and implies that the current atmospheric reservoirs of CO 2 and H 2 O were largely established after the period of early atmosphe...

Mars' Atmosphere from Curiosity The Sample Analysis at Mars (SAM) instrument on the Curiosity rover that landed on Mars in August last year is designed to study the chemical and isotopic composition of the martian atmosphere. Mahaffy... more

Mars' Atmosphere from Curiosity The Sample Analysis at Mars (SAM) instrument on the Curiosity rover that landed on Mars in August last year is designed to study the chemical and isotopic composition of the martian atmosphere. Mahaffy et al. (p. 263 ) present volume-mixing ratios of Mars' five major atmospheric constituents (CO 2 , Ar, N 2 , O 2 , and CO) and isotope measurements of 40 Ar/ 36 Ar and C and O in CO 2 , based on data from one of SAM's instruments, obtained between 31 August and 21 November 2012. Webster et al. (p. 260 ) used data from another of SAM's instruments obtained around the same period to determine isotope ratios of H, C, and O in atmospheric CO 2 and H 2 O. Agreement between the isotopic ratios measured by SAM with those of martian meteorites, measured in laboratories on Earth, confirms the origin of these meteorites and implies that the current atmospheric reservoirs of CO 2 and H 2 O were largely established after the period of early atmosphe...

As space exploration advances, the importance of tapping resources from other planets, known as In-Situ Resource Utilization (ISRU), becomes increasingly vital to reduce the cost of resupply missions. On Mars, resources such as water,... more

As space exploration advances, the importance of tapping resources from other planets, known as
In-Situ Resource Utilization (ISRU), becomes increasingly vital to reduce the cost of resupply
missions. On Mars, resources such as water, regolith, light, and CO2 can be used to grow food, and
previous studies have demonstrated the possibility of growing plants such as Arabidopsis thaliana
in Martian regolith simulants such as JSC-1 and MMS-1. This study focuses on the development,
impact on stress related genes, and the survivability of OsSnRK1a and OsTOR mutants of rice
plants grown in MMS1. Results showed that plants grown in pure MMS1 had stunted growth, poor
root morphology, and lower photosynthetic activity, but the addition of any proportion of PM in
MMS1 improved growth and root characteristics compared to 100% MMS1. While the rice plants
showed signs of stress in MMS1, the study suggests that the physical and chemical characteristics
of MMS1 can support their growth, provided the levels of (Mg(ClO4)2) are kept in check.
Additionally, the study provides evidence that rice plant with OsSnRK1a mutation has the
potential to germinate and grow in MMS1 with (Mg(ClO4)2). Overall, the results demonstrate that
it is possible to grow rice plants in Martian regolith and is improved by amending the soil with
potting mix and editing specific rice genes to promote survivability.

SEPARATE LAUNCH SITES ON MARS. A. J. Irving, S. M. Kuehner, T. J. Lapen, M. Righter, H. Busemann, R. Wieler and K. Nishiizumi Dept. of Earth & Space Sciences, University of Washington, Seattle, WA (irvingaj@uw.edu), Dept. of Earth &... more

SEPARATE LAUNCH SITES ON MARS. A. J. Irving, S. M. Kuehner, T. J. Lapen, M. Righter, H. Busemann, R. Wieler and K. Nishiizumi Dept. of Earth & Space Sciences, University of Washington, Seattle, WA (irvingaj@uw.edu), Dept. of Earth & Atmospheric Sciences, University of Houston, TX, Inst. für Geochemie & Petrologie, ETH Zürich, Switzerland, Space Sciences Laboratory, University of California, Berkeley, CA.

Multiple lines of evidence indicate an active hydrogeological history of Mars and chemolithoautotrophy-suited environments within its Noachian terrains. As a result, one of the primary aims of upcoming missions to Mars is to search for... more

Multiple lines of evidence indicate an active hydrogeological history of Mars and chemolithoautotrophy-suited environments within its Noachian terrains. As a result, one of the primary aims of upcoming missions to Mars is to search for signs of ancient life. Here we report on laboratory-scaled microbially assisted chemolithoautotrophic biotransformation of the Noachian Martian breccia Northwest Africa (NWA) 7034 composed of ancient (~4.5 Gyr old) crustal materials from Mars. Nanoanalytical hyperspectral analysis provides clues for the trafficking and distribution of meteorite inorganic constituents in the microbial cell. We decipher biomineralization patterns associated with the biotransformation and reveal microbial nanometer-sized lithologies located inside the cell and on its outer surface layer. These investigations provide an opportunity to trace the putative bioalteration processes of the Martian crust and to assess the potential biogenicity of Martian materials.

The Tissint Martian meteorite is an unusual depleted olivine-phyric shergottite, reportedly sourced from a mantle-derived melt within a deep magma chamber. Here, we report major and trace element data for Tissint olivine and pyroxene, and... more

The Tissint Martian meteorite is an unusual depleted olivine-phyric shergottite, reportedly sourced from a mantle-derived melt within a deep magma chamber. Here, we report major and trace element data for Tissint olivine and pyroxene, and use these data to provide new insights into the dynamics of the Tissint magma chamber. The presence of irregularly spaced oscillatory phosphorous (P)-rich bands in olivine, along with geochemical evidence indicative of a closed magmatic system, implies that the olivine grains were subject to solute trapping caused by vigorous crystal convection within the Tissint magma chamber. Calculated equilibration temperatures for the earliest crystallizing (antecrystic) olivine cores suggest a Tissint magma source temperature of 1680°C, and a local Martian mantle temperature of 1560°C during the late Amazonian-the latter being consistent with the ambient mantle temperature of Archean Earth.

Northwest Africa 5790, the latest nakhlite find, is composed of 58 vol.% augite, 6% olivine and 36% vitrophyric intercu-mulus material. Its petrology is comparable to previously discovered nakhlites but with key differences: (1) Augite... more

Northwest Africa 5790, the latest nakhlite find, is composed of 58 vol.% augite, 6% olivine and 36% vitrophyric intercu-mulus material. Its petrology is comparable to previously discovered nakhlites but with key differences: (1) Augite cores display an unusual zoning between Mg# 54 and 60; (2) Olivine macrocrysts have a primary Fe-rich core composition (Mg# = 35); (3) The modal proportion of mesostasis is the highest ever described in a nakhlite; (4) It is the most magnetite-rich nakhlite, together with MIL 03346, and exhibits the least anisotropic fabric. Complex primary zoning in cumu-lus augite indicates resorption due to complex processes such as remobilization of former cumulates in a new magma batch. Textural relationships indicate unambiguously that olivine was growing around resorbed augite, and that olivine growth was continuous while pyroxene growth resumed at a final stage. Olivine core compositions (Mg# = 35) are out of equilibrium with the augite core compositions (Mg# 60–63) and with the previously inferred nakhlite parental magma (Mg# = 29). The presence of oscillatory zoning in olivine and augite precludes subsolidus diffusion that could have modified olivine compositions. NWA 5790 evidences at least two magma batches before eruption, with the implication that melt in equilibrium with augite cores was never in contact with olivine. Iddingsite is absent. Accordingly, the previous scenarios for nakhlite petrogenesis must be revised. The first primary parent magmas of nakh-lites generated varied augite cumulates at depth (Mg# 66–60) as they differentiated to different extents. A subsequent more evolved magma batch entrained accumulated augite crystals to the surface where they were partly resorbed while olivine crystallized. Trace element variations indicate unambiguously that they represent consanguineous but different magma batches. The compositional differences among the various nakhlites suggest a number of successive lava flows. To account for all observations we propose a petrogenetic model for nakhlites based on several (at least three) thick flows. Although NWA 5790 belongs to the very top of one flow, it should come from the lowest flow sampled, based on the lack of iddingsite.

–We report precise triple oxygen isotope data of bulk materials and separated fractions of several Shergotty–Nakhla–Chassigny (SNC) meteorites using enhanced laser-assisted fluorination technique. This study shows that SNCs have... more

–We report precise triple oxygen isotope data of bulk materials and separated fractions of several Shergotty–Nakhla–Chassigny (SNC) meteorites using enhanced laser-assisted fluorination technique. This study shows that SNCs have remarkably identical D 17 O and a narrow range in d 18 O values suggesting that these meteorites have assimilated negligibly small surface materials (<5%), which is undetectable in the oxygen isotope compositions reported here. Also, fractionation factors in coexisting silicate mineral pairs (px-ol and mask-ol) further demonstrate isotopic equilibrium at magmatic temperatures. We present a mass-dependent fractionation line for bulk materials with a slope of 0.526 AE 0.016 (1SE) comparable to the slope obtained in an earlier study (0.526 AE 0.013; Franchi et al. 1999). We also present a new Martian fractionation line for SNCs constructed from separated fractions (i.e., pyroxene, olivine, and maskelynite) with a slope of 0.532 AE 0.009 (1SE). The identical fractionation lines run above and parallel to our terrestrial fractionation line with D 17 O = 0.318 AE 0.016& (SD) for bulk materials and 0.316 AE 0.009& (SD) for separated fractions. The conformity in slopes and D 17 O between bulk materials and separated fractions confirm oxygen isotope homogeneity in the Martian mantle though recent studies suggest that the Martian lithosphere may potentially have multiple oxygen isotope reservoirs.

Northwest Africa (NWA) 7034 and its paired meteorites NWA 7533 and NWA 7475 are the first recognized martian polymict breccia samples. An unusual, large, subrounded clast in NWA 7034 shows a vitrophyric texture, consisting of skeletal... more

Northwest Africa (NWA) 7034 and its paired meteorites NWA 7533 and NWA 7475 are the first recognized martian polymict breccia samples. An unusual, large, subrounded clast in NWA 7034 shows a vitrophyric texture, consisting of skeletal pyroxene and olivine with mesostasis. This lithology has not been observed in the paired meteorites. It crystallized under disequilibrium conditions as indicated by its olivine and pyroxene K D Fe/Mg partitioning values, as well as reversed order of crystallization and mineral compositions relative to those predicted by MELTS. We report the highest bulk Ni value (1020 ppm) measured in any known martian meteorite or martian igneous rock, suggesting an impact melt origin for the vit-rophyre. Addition of 5.3–7.7% chondritic material to the target rock would account for the Ni enrichment. The bulk major and trace element abundances of the vitrophyre indicate that the protolith was not the host breccia nor any other martian meteorites. However, the clast is compositionally similar to Humphrey rock in Gusev crater analyzed by the Spirit rover and to a texturally distinct group of clasts in the paired meteorite NWA 7533. Thus, we propose that the target rock was an igneous lithology similar to Gusev basalts, which was subsequently contaminated by a chondritic impactor.

Abstract— Dynamic crystallization experiments performed on Fe-rich, Al-poor basalt are employed as a textural calibration set to quantify the late-stage igneous history of nakhlite Miller Range (MIL) 03346. The ratio of crystal-melt... more

Abstract— Dynamic crystallization experiments performed on Fe-rich, Al-poor basalt are employed as a textural calibration set to quantify the late-stage igneous history of nakhlite Miller Range (MIL) 03346. The ratio of crystal-melt surface area to volume typifying morphologically distinct populations of Ca-pyroxene has been shown to vary as a strong function of cooling rate (Hammer 2006). Furthermore, a texture of phenocrysts surrounded by finer-grained groundmass crystals arises by sequential nucleation events during constant-rate cooling, but multiple populations nucleate only if the cooling rate is 72 °C h−1. Textural analysis of meteorite MIL 03346 reveals at least two distinct populations. The Ca-pyroxene phenocryst and microphenocryst three dimensional (3D) aspect ratios are 112 ± 8.3 and 1530 ± 160 mm−1, respectively. By comparison with the calibration set, the range of cooling rates consistent with 3D aspect ratios of both populations in MIL 03346 is ˜20 °C h−1An additional experiment was performed approximating a conductive heat transfer profile in order to interpret and apply results of constant-rate cooling experiments to the natural cooling of magma. Results suggest that the textures of constant-rate experiments parallel the initial period of rapid cooling in natural magma. Initial cooling rates of ˜20 °C h−1in the lava hosting MIL 03346 occur in conductively solidifying lava at depths of˜0.4 m, constraining the minimum total thickness to 0.8 m. Crystal accumulation beginning in a subsurface reservoir and continuing after lava emplacement as an inflated pahoehoe sheet satisfies all textural constraints on the late-stage igneous history of MIL 03346.

There is an overwhelming amount of evidence supporting the past existence of abundant flowing water on the martian surface, however the source for this water is less understood. Estimates of water in the deep martian interior from SNC... more

There is an overwhelming amount of evidence supporting the past existence of abundant flowing water on the martian surface, however the source for this water is less understood. Estimates of water in the deep martian interior from SNC meteorites yield low values (1–36 ppm H2O) that are incompatible with magmatic degassing as the primary source for this water. We have analyzed hydrous amphibole in the Chassigny martian meteorite, finding much higher water contents than previously reported. These values are consistent with a much wetter martian mantle (minimum range of 140–250 ppm H2O for the Chassigny source region), allowing for significant contributions of water to the martian surface by magmatic degassing. Furthermore, these results indicate the possibility of young (early–mid Amazonian), water-rich hydrothermal activity at the surface and subsurface, which could have been responsible for intermittent replenishment of water to these regions even after the onset of the cold dry climate that exists today.