scholarly journals A Mineralogical Context for the Organic Matter in the Paris Meteorite Determined by A Multi-Technique Analysis

Life ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 44
Author(s):  
Manale Noun ◽  
Donia Baklouti ◽  
Rosario Brunetto ◽  
Ferenc Borondics ◽  
Thomas Calligaro ◽  
...  

This study is a multi-technique investigation of the Paris carbonaceous chondrite directly applied on two selected 500 × 500 µm² areas of a millimetric fragment, without any chemical extraction. By mapping the partial hydration of the amorphous silicate phase dominating the meteorite sample matrix, infrared spectroscopy gave an interesting glimpse into the way the fluid may have circulated into the sample and partially altered it. The TOF-SIMS in-situ analysis allowed the studying and mapping of the wide diversity of chemical moieties composing the meteorite organic content. The results of the combined techniques show that at the micron scale, the organic matter was always spatially associated with the fine-grained and partially-hydrated amorphous silicates and to the presence of iron in different chemical states. These systematic associations, illustrated in previous studies of other carbonaceous chondrites, were further supported by the identification by TOF-SIMS of cyanide and/or cyanate salts that could be direct remnants of precursor ices that accreted with dust during the parent body formation, and by the detection of different metal-containing large organic ions. Finally, the results obtained emphasized the importance of studying the specific interactions taking place between organic and mineral phases in the chondrite matrix, in order to investigate their role in the evolution story of primitive organic matter in meteorite parent bodies.

1980 ◽  
Vol 20 (1) ◽  
pp. 44 ◽  
Author(s):  
A.C. Hutton ◽  
A.J. Kantsler ◽  
A.C. Cook ◽  
D.M. McKirdy

The Tertiary oil-shale deposits at Rundle in Queensland and of the Green River Formation in the western USA, together with Mesozoic deposits such as those at Julia Creek in Queensland, offer prospects of competitive recovery cost through the use of large-scale mining methods or the use of in situ processing.A framework for the classification of oil shales is proposed, based on the origin and properties of the organic matter. The organic matter in most Palaeozoic oil shales is dominantly large, discretely occurring algal bodies, referred to as alginite A. However, Tertiary oil shales of northeastern Australia are chiefly composed of numerous very thin laminae of organic matter cryptically-interbedded with mineral matter. Because the present maceral nomenclature does not adequately encompass the morphological and optical properties of most organic matter in oil shales, it is proposed to use the term alginite B for finely lamellar alginite, and the term lamosites (laminated oil shales) for oil shales which contain alginite B as their dominant organic constituent. In the Julia Creek oil shale the organic matter is very fine-grained and contains some alginite B but has a higher content of alginite A and accordingly is assigned to a suite of oil shales of mixed origin.Petrological and chemical techniques are both useful in identifying the nature and diversity of organic matter in oil shales and in assessing the environments in which they were formed. Such an understanding is necessary to develop exploration concepts for oil shales.


2014 ◽  
Vol 131 ◽  
pp. 368-392 ◽  
Author(s):  
Corentin Le Guillou ◽  
Sylvain Bernard ◽  
Adrian J. Brearley ◽  
Laurent Remusat

2019 ◽  
Vol 5 (3) ◽  
pp. 127-147
Author(s):  
Marjolaine Verret ◽  
Yifeng Wang ◽  
Jean Bjornson ◽  
Denis Lacelle

Hummocks develop by cryoturbation in fine-grained frost-susceptible soils and their stage of maturity may affect the translocation of organics in Cryosols. This study examines the distribution and morphology of hummocks in the Chuck Creek Trail Valley (northern British Columbia) and determines the quantity, distribution, and composition of organic matter in their soils. Hummocks occupy about 5%–20% of the valley and their morphology is largely affected by their silt content. Cryoturbated intrusions, radiocarbon dated to 2814 and 1648 cal year B.P., suggest that hummock development was initiated during the cooler late Holocene. Hummocks have an average soil organic carbon density of 16.3 kg m−2 in the uppermost 1 m, with 62% stored in the top 25 cm. Organics are mainly present as particulate organic matter in the O-horizon (25%–80%), characterized by degradable alkyl C and O/N-alkyl groups, but occur as mineral-associated organic matter (96%–98%) composed of recalcitrant aromatic and aliphatic C groups in the underlying B and C horizons. Minor differences in organic content and composition occur between hummock tops and troughs, and between hummocks showing different stages of maturity. In the absence of an observed frost table, contemporary hummock activity is attributed to seasonal freezing and thawing.


2020 ◽  
Author(s):  
Feifei Jia ◽  
Jie Wang ◽  
Yanyan Zhang ◽  
Qun Luo ◽  
Luyu Qi ◽  
...  

<p></p><p><i>In situ</i> visualization of proteins of interest at single cell level is attractive in cell biology, molecular biology and biomedicine, which usually involves photon, electron or X-ray based imaging methods. Herein, we report an optics-free strategy that images a specific protein in single cells by time of flight-secondary ion mass spectrometry (ToF-SIMS) following genetic incorporation of fluorine-containing unnatural amino acids as a chemical tag into the protein via genetic code expansion technique. The method was developed and validated by imaging GFP in E. coli and human HeLa cancer cells, and then utilized to visualize the distribution of chemotaxis protein CheA in E. coli cells and the interaction between high mobility group box 1 protein and cisplatin damaged DNA in HeLa cells. The present work highlights the power of ToF-SIMS imaging combined with genetically encoded chemical tags for <i>in situ </i>visualization of proteins of interest as well as the interactions between proteins and drugs or drug damaged DNA in single cells.</p><p></p>


2021 ◽  
pp. 089331892199807
Author(s):  
Jonathan Clifton ◽  
Fernando Fachin ◽  
François Cooren

To date there has been little work that uses fine-grained interactional analyses of the in situ doing of leadership to make visible the role of non-human as well as human actants in this process. Using transcripts of naturally-occurring interaction as data, this study seeks to show how leadership is co-achieved by artefacts as an in-situ accomplishment. To do this we situate this study within recent work on distributed leadership and argue that it is not only distributed across human actors, but also across networks that include both human and non-human actors. Taking a discursive approach to leadership, we draw on Actor Network Theory and adopt a ventriloquial approach to sociomateriality as inspired by the Montreal School of organizational communication. Findings indicate that artefacts “do” leadership when a hybrid presence is made relevant to the interaction and when this presence provides authoritative grounds for influencing others to achieve the group’s goals.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Q. H. S. Chan ◽  
A. Stephant ◽  
I. A. Franchi ◽  
X. Zhao ◽  
R. Brunetto ◽  
...  

AbstractUnderstanding the true nature of extra-terrestrial water and organic matter that were present at the birth of our solar system, and their subsequent evolution, necessitates the study of pristine astromaterials. In this study, we have studied both the water and organic contents from a dust particle recovered from the surface of near-Earth asteroid 25143 Itokawa by the Hayabusa mission, which was the first mission that brought pristine asteroidal materials to Earth’s astromaterial collection. The organic matter is presented as both nanocrystalline graphite and disordered polyaromatic carbon with high D/H and 15N/14N ratios (δD =  + 4868 ± 2288‰; δ15N =  + 344 ± 20‰) signifying an explicit extra-terrestrial origin. The contrasting organic feature (graphitic and disordered) substantiates the rubble-pile asteroid model of Itokawa, and offers support for material mixing in the asteroid belt that occurred in scales from small dust infall to catastrophic impacts of large asteroidal parent bodies. Our analysis of Itokawa water indicates that the asteroid has incorporated D-poor water ice at the abundance on par with inner solar system bodies. The asteroid was metamorphosed and dehydrated on the formerly large asteroid, and was subsequently evolved via late-stage hydration, modified by D-enriched exogenous organics and water derived from a carbonaceous parent body.


2021 ◽  
pp. 014459872110310
Author(s):  
Min Li ◽  
Xiongqi Pang ◽  
Guoyong Liu ◽  
Di Chen ◽  
Lingjian Meng ◽  
...  

The fine-grained rocks in the Paleogene Shahejie Formation in Nanpu Sag, Huanghua Depression, Bohai Bay Basin, are extremely important source rocks. These Paleogene rocks are mainly subdivided into organic-rich black shale and gray mudstone. The average total organic carbon contents of the shale and mudstone are 11.5 wt.% and 8.4 wt.%, respectively. The average hydrocarbon (HC)-generating potentials (which is equal to the sum of free hydrocarbons (S1) and potential hydrocarbons (S2)) of the shale and mudstone are 39.3 mg HC/g rock and 28.5 mg HC/g rock, respectively, with mean vitrinite reflectance values of 0.82% and 0.81%, respectively. The higher abundance of organic matter in the shale than in the mudstone is due mainly to paleoenvironmental differences. The chemical index of alteration values and Na/Al ratios reveal a warm and humid climate during shale deposition and a cold and dry climate during mudstone deposition. The biologically derived Ba and Ba/Al ratios indicate high productivity in both the shale and mudstone, with relatively low productivity in the shale. The shale formed in fresh to brackish water, whereas the mudstone was deposited in fresh water, with the former having a higher salinity. Compared with the shale, the mudstone underwent higher detrital input, exhibiting higher Si/Al and Ti/Al ratios. Shale deposition was more dysoxic than mudstone deposition. The organic matter enrichment of the shale sediments was controlled mainly by reducing conditions followed by moderate-to-high productivity, which was promoted by a warm and humid climate and salinity stratification. The organic matter enrichment of the mudstone was less than that of the shale and was controlled by relatively oxic conditions.


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