The secondary history of Sutter's Mill CM carbonaceous chondrite based on water abundance and the structure of its organic matter from two clasts

2014 ◽  
Vol 49 (11) ◽  
pp. 2064-2073 ◽  
Author(s):  
P. Beck ◽  
E. Quirico ◽  
A. Garenne ◽  
Q.-Z. Yin ◽  
L. Bonal ◽  
...  
Keyword(s):  
Organic Matter ◽  
Carbonaceous Chondrite ◽  
Water Abundance ◽  
History Of

Elements for a General Organology

Derrida Today ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 72-94
Author(s):  
Bernard Stiegler
Keyword(s):  
Organic Matter ◽  
Planetary Scale ◽  
General Account ◽  
Inorganic Matter ◽  
History Of

These lectures outline the project of a general organology, which is to say an account of life when it is no longer just biological but technical, or when it involves not just organic matter but organized inorganic matter. This organology is also shown to require a modified Simondonian account of the shift from vital individuation to a three-stranded process of psychic, collective and technical individuation. Furthermore, such an approach involves extending the Derridean reading of Socrates's discussion of writing as a pharmakon, so that it becomes a more general account of the pharmacological character of retention and protention. By going back to Leroi-Gourhan, we can recognize that this also means pursuing the history of retentional modifications unfolding in the course of the history of what, with Lotka, can also be called exosomatization. It is thus a question of how exteriorization can, today, in an epoch when it becomes digital, and in an epoch that produces vast amounts of entropy at the thermodynamic, biological and noetic levels, still possibly produce new forms of interiorization, that is, new forms of thought, care and desire, amounting to so many chances to struggle against the planetary-scale pharmacological crisis with which we are currently afflicted.

scholarly journals Life History of Lepidostoma hirtum in an Iberian Stream and its Role in Organic Matter Processing

Hydrobiologia ◽  
2006 ◽  
Vol 559 (1) ◽  
pp. 183-192 ◽  
Author(s):  
H. V. S. Azevedo-Pereira ◽  
M. A. S. Graça ◽  
J. M. González
Keyword(s):  
Organic Matter ◽  
Life History ◽  
History Of ◽  
Organic Matter Processing

scholarly journals Relationships between depositional conditions and microtextures in the organic-rich Lower Oxford Clay sediments (U.K.)

1992 ◽  
Vol 6 ◽  
pp. 24-24
Author(s):  
Sophie Belin ◽  
Fabien Kenig
Keyword(s):  
Organic Matter ◽  
Sedimentation Rate ◽  
Woody Debris ◽  
Carbon Isotopic ◽  
Reducing Conditions ◽  
Geochemical Parameters ◽  
Energy Environment ◽  
Electron Mode ◽  
History Of ◽  
Quartz Grains

Six representative samples of the Lower Oxford Clay (LOC) and the Middle Oxford Clay (MOC) sediments have been assessed for total organic carbon (TOC from 1.2 to 14.2%), hydrogen indices (HI from 813 to 130), and carbon isotopic values (δ13C from −23.1 to −27.7±) (Kenig et al., this symposium), and have been extensively studied using petrographic techniques. The use of the scanning electron microscope and particularly the backscattered electron mode was emphasized as it is the most suitable tool to study the relationships between organic matter and minerals at a micrometric scale.The bulk mineralogy appears similar in all samples studied. The argillaceous matrix is predominantly composed of illite and kaolinite with detrital mineral grains of quartz, feldspar, mica (biotite and muscovite) and calcitic bioclasts (e.g. coccoliths). Diagenetic features consist mainly of dissolution of quartz grains, rim epigenization of quartz grains to kaolinite, and the presence of pyrite. The concentration of pyrite increases with the concentration of organic matter. Both framboidal and euhedral forms of pyrite are present Euhedral pyrite crystals are more abundant in organic-rich samples, indicative of the more reducing conditions occurring in the organic-rich sediments. In organic-rich samples, coccoliths are concentrated in well preserved fecal pellets, suggesting a relatively high sedimentation rate. Preservation of coccospheres indicates a low energy environment of deposition and mild diagenesis. Unusually well-preserved biotite crystals may be indicative of the proximity of sediment sources and of the weakness of diagenetic processes.In organic-rich samples, organic matter is encountered as elongated “patches” 20 to 50 μm in length and composed of several particles of marine phytoplanktonic origin; and as thin isolated particles closely associated with clays. These thin particles are both of marine phytoplanktonic and of terrestrial origin (woody debris, vegetal tissues and rare palynomorphs). In organic-poor samples, the frequency and the size (5 to 20 μm) of the patchy composite particles of phytoplanktonic organic matter decrease. Palynological studies indicated that 80% to 95% of the organic matter is amorphous and probably of marine origin. However, the proportion of structured organic matter, woody debris and vegetal tissues, increases from 5% to 20% as the TOC decreases.None of the samples studied exhibited laminations at a sub-millimetric scale. However, the organic “patches” in the organic-rich samples lie parallel to the plane of stratification even if there is no obvious stratification of the mineral matrix. Clay minerals show a random and disorganized distribution that may be indicative of microbioturbation, even in the most organic-rich samples.Organic and mineral microtextures are controlled by the environment of deposition and the diagenetic history of the sediments and are related to geochemical parameters as HI, δ13C and TOC. Microbioturbation would indicate that the water column was never anoxic. In contrast, euhedral pyrites crystals suggest anoxia in the organic-rich sediments. The decrease in size of organic “patches” with decrease in TOC, as well as the variable distribution of coccoliths, may be indicative of changes in primary productivity and sedimentation rate.

Recent Sedimentary History of Organic Matter and Nutrient Accumulation in the Ohuira Lagoon, Northwestern Mexico

2007 ◽  
Vol 53 (2) ◽  
pp. 159-167 ◽  
Author(s):  
Ana Carolina Ruiz-Fernández ◽  
Mauro Frignani ◽  
Tommaso Tesi ◽  
Humberto Bojórquez-Leyva ◽  
Luca Giorgio Bellucci ◽  
...  
Keyword(s):  
Organic Matter ◽  
Nutrient Accumulation ◽  
History Of ◽  
Northwestern Mexico

XV.—An Investigation into the Structure and Life-History of the Sulphur Bacteria (I)

1925 ◽  
Vol 44 ◽  
pp. 153-167
Author(s):  
David Ellis
Keyword(s):  
Organic Matter ◽  
Life History ◽  
Protein Molecule ◽  
Shallow Waters ◽  
Naked Eye ◽  
Full Development ◽  
Sulphur Bacteria ◽  
History Of ◽  
Abundant Supply ◽  
Sulphuretted Hydrogen

The sulphur bacteria are found in shallow waters, both marine and fresh, and play an active part in the decomposition of animal and vegetable matter. They require for their full development an abundant supply of oxygen and of sulphuretted hydrogen. They do not thrive unless the water is periodically renewed, or else is so shallow that oxygen is obtainable to a fairly large extent from the atmosphere. When the oxygen is used up their development rapidly comes to an end, and in some cases, as is described below, the organisms disappear completely. They derive their supply of sulphuretted hydrogen from the decomposition of the protein molecule of vegetable and animal matter. Usually a growth of sulphur bacteria is visible to the naked eye as a greyish or reddish mantle covering the surface of a mass of decomposing organic matter. If, for some reason or other, the supply of oxygen is not plentiful at the bottom of the pool, the mass of growth leaves the surface of the decomposing matter and moves nearer the surface of the water.

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