Study of the diagenesis, catagenesis and metagenesis of coals and dispersed organic matter with a high-temperature modified Rock—Eval

1985 ◽  
pp. 319-326
Author(s):  
Paul Leplat ◽  
Jacques Paulet
Keyword(s):  
Organic Matter ◽  
High Temperature ◽  
Rock Eval

scholarly journals Composition of Sedimentary Organic Matter across the Laptev Sea Shelf: Evidences from Rock-Eval Parameters and Molecular Indicators

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3511
Author(s):  
Elena Gershelis ◽  
Andrey Grinko ◽  
Irina Oberemok ◽  
Elizaveta Klevantseva ◽  
Natalina Poltavskaya ◽  
...  
Keyword(s):  
Organic Matter ◽  
Surface Sediments ◽  
Continental Margins ◽  
Laptev Sea ◽  
Lena River ◽  
Nearshore Sediments ◽  
Rock Eval ◽  
Molecular Indicators ◽  
Sedimentation Regime ◽  
The Laptev Sea

Global warming in high latitudes causes destabilization of vulnerable permafrost deposits followed by massive thaw-release of organic carbon. Permafrost-derived carbon may be buried in the nearshore sediments, transported towards the deeper basins or degraded into the greenhouse gases, potentially initiating a positive feedback to climate change. In the present study, we aim to identify the sources, distribution and degradation state of organic matter (OM) stored in the surface sediments of the Laptev Sea (LS), which receives a large input of terrestrial carbon from both Lena River discharge and intense coastal erosion. We applied a suite of geochemical indicators including the Rock Eval parameters, traditionally used for the matured OM characterization, and terrestrial lipid biomarkers. In addition, we analyzed a comprehensive grain size data in order to assess hydrodynamic sedimentation regime across the LS shelf. Rock-Eval (RE) data characterize LS sedimentary OM with generally low hydrogen index (100–200 mg HC/g TOC) and oxygen index (200 and 300 CO2/g TOC) both increasing off to the continental slope. According to Tpeak values, there is a clear regional distinction between two groups (369–401 °C for the inner and mid shelf; 451–464 °C for the outer shelf). We suggest that permafrost-derived OM is traced across the shallow and mid depths with high Tpeak and slightly elevated HI values if compared to other Arctic continental margins. Molecular-based degradation indicators show a trend to more degraded terrestrial OC with increasing distance from the coast corroborating with RE results. However, we observed much less variation of the degradation markers down to the deeper sampling horizons, which supports the notion that the most active OM degradation in LS land-shelf system takes part during the cross-shelf transport, not while getting buried deeper.

scholarly journals Fire-Safe Polymer Composites: Flame-Retardant Effect of Nanofillers

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 540
Author(s):  
Yukyung Kim ◽  
Sanghyuck Lee ◽  
Hyeonseok Yoon
Keyword(s):  
Organic Matter ◽  
High Temperature ◽  
Flame Retardant ◽  
Flame Retardants ◽  
Combustion Process ◽  
Polymeric Materials ◽  
Fire Performance ◽  
Gaseous Species ◽  
Advantages And Disadvantages ◽  
Temperature Conditions

Currently, polymers are competing with metals and ceramics to realize various material characteristics, including mechanical and electrical properties. However, most polymers consist of organic matter, making them vulnerable to flames and high-temperature conditions. In addition, the combustion of polymers consisting of different types of organic matter results in various gaseous hazards. Therefore, to minimize the fire damage, there has been a significant demand for developing polymers that are fire resistant or flame retardant. From this viewpoint, it is crucial to design and synthesize thermally stable polymers that are less likely to decompose into combustible gaseous species under high-temperature conditions. Flame retardants can also be introduced to further reinforce the fire performance of polymers. In this review, the combustion process of organic matter, types of flame retardants, and common flammability testing methods are reviewed. Furthermore, the latest research trends in the use of versatile nanofillers to enhance the fire performance of polymeric materials are discussed with an emphasis on their underlying action, advantages, and disadvantages.

Comparison of the mineralogical effects of an experimental forest fire on a goethite/ferrihydrite soil with a topsoil that contains hematite, maghemite and goethite

Clay Minerals ◽  
2009 ◽  
Vol 44 (2) ◽  
pp. 239-247 ◽  
Author(s):  
P. Nørnberg ◽  
A. L. Vendelboe ◽  
H. P. Gunnlaugsson ◽  
J. P. Merrison ◽  
K. Finster ◽  
...  
Keyword(s):  
Organic Matter ◽  
High Temperature ◽  
Forest Fire ◽  
Forest Fires ◽  
Organic Matter Content ◽  
Matter Content ◽  
Humid Climate ◽  
Fe Mineralogy ◽  
Reducing Environment

AbstractA long-standing unresolved puzzle related to the Danish temperate humid climate is the presence of extended areas with large Fe contents, where goethite and ferrihydrite are present in the topsoil along with hematite and maghemite. Hematite and, particularly, maghemite would normally be interpreted as the result of high temperature as found after forest fires. However, a body of evidence argues against these sites having been exposed to fire. In an attempt to get closer to an explanation of this Fe mineralogy, an experimental forest fire was produced. The results showed a clear mineralogical zonation down to 10 cm depth. This was not observed at the natural sites, which contained a mixture of goethite/ferrihydrite, hematite and maghemite down to 20 cm depth. The experimental forest fire left charcoal and ashes at the topsoil, produced high pH and decreased organic matter content, all of which is in contrast to the natural sites. The conclusion from this work is that the mineralogy of these sites is not consistent with exposure to forest fire, but may instead result from long-term transformation in a reducing environment, possibly involving microbiology.

scholarly journals Source rock characterization of mesozoic to cenozoic organic matter rich marls and shales of the Eratosthenes Seamount, Eastern Mediterranean Sea

2018 ◽  
Vol 73 ◽  
pp. 49 ◽  
Author(s):  
Sebastian Grohmann ◽  
Susanne W. Fietz ◽  
Ralf Littke ◽  
Samer Bou Daher ◽  
Maria Fernanda Romero-Sarmiento ◽  
...  
Keyword(s):  
Organic Matter ◽  
Mediterranean Sea ◽  
Source Rock ◽  
Eastern Mediterranean ◽  
Source Rocks ◽  
Eastern Mediterranean Sea ◽  
Potential Source Rock ◽  
Levant Basin ◽  
Rock Characterization ◽  
Rock Eval

Several significant hydrocarbon accumulations were discovered over the past decade in the Levant Basin, Eastern Mediterranean Sea. Onshore studies have investigated potential source rock intervals to the east and south of the Levant Basin, whereas its offshore western margin is still relatively underexplored. Only a few cores were recovered from four boreholes offshore southern Cyprus by the Ocean Drilling Program (ODP) during the drilling campaign Leg 160 in 1995. These wells transect the Eratosthenes Seamount, a drowned bathymetric high, and recovered a thick sequence of both pre- and post-Messinian sedimentary rocks, containing mainly marine marls and shales. In this study, 122 core samples of Late Cretaceous to Messinian age were analyzed in order to identify organic-matter-rich intervals and to determine their depositional environment as well as their source rock potential and thermal maturity. Both Total Organic and Inorganic Carbon (TOC, TIC) analyses as well as Rock-Eval pyrolysis were firstly performed for the complete set of samples whereas Total Sulfur (TS) analysis was only carried out on samples containing significant amount of organic matter (>0.3 wt.% TOC). Based on the Rock-Eval results, eight samples were selected for organic petrographic investigations and twelve samples for analysis of major aliphatic hydrocarbon compounds. The organic content is highly variable in the analyzed samples (0–9.3 wt.%). TS/TOC as well as several biomarker ratios (e.g. Pr/Ph < 2) indicate a deposition under dysoxic conditions for the organic matter-rich sections, which were probably reached during sporadically active upwelling periods. Results prove potential oil prone Type II kerogen source rock intervals of fair to very good quality being present in Turonian to Coniacian (average: TOC = 0.93 wt.%, HI = 319 mg HC/g TOC) and in Bartonian to Priabonian (average: TOC = 4.8 wt.%, HI = 469 mg HC/g TOC) intervals. A precise determination of the actual source rock thickness is prevented by low core recovery rates for the respective intervals. All analyzed samples are immature to early mature. However, the presence of deeper buried, thermally mature source rocks and hydrocarbon migration is indicated by the observation of solid bitumen impregnation in one Upper Cretaceous and in one Lower Eocene sample.

scholarly journals A Mesoproterozoic iron formation

2018 ◽  
Vol 115 (17) ◽  
pp. E3895-E3904 ◽  
Author(s):  
Donald E. Canfield ◽  
Shuichang Zhang ◽  
Huajian Wang ◽  
Xiaomei Wang ◽  
Wenzhi Zhao ◽  
...  
Keyword(s):  
Organic Matter ◽  
Time Window ◽  
Iron Formation ◽  
The North ◽  
Fe Oxidation ◽  
Organic Biomarkers ◽  
Rock Eval ◽  
Fe Reduction ◽  
Rule Out ◽  
Xiamaling Formation

We describe a 1,400 million-year old (Ma) iron formation (IF) from the Xiamaling Formation of the North China Craton. We estimate this IF to have contained at least 520 gigatons of authigenic Fe, comparable in size to many IFs of the Paleoproterozoic Era (2,500–1,600 Ma). Therefore, substantial IFs formed in the time window between 1,800 and 800 Ma, where they are generally believed to have been absent. The Xiamaling IF is of exceptionally low thermal maturity, allowing the preservation of organic biomarkers and an unprecedented view of iron-cycle dynamics during IF emplacement. We identify tetramethyl aryl isoprenoid (TMAI) biomarkers linked to anoxygenic photosynthetic bacteria and thus phototrophic Fe oxidation. Although we cannot rule out other pathways of Fe oxidation, iron and organic matter likely deposited to the sediment in a ratio similar to that expected for anoxygenic photosynthesis. Fe reduction was likely a dominant and efficient pathway of organic matter mineralization, as indicated by organic matter maturation by Rock Eval pyrolysis combined with carbon isotope analyses: Indeed, Fe reduction was seemingly as efficient as oxic respiration. Overall, this Mesoproterozoic-aged IF shows many similarities to Archean-aged (>2,500 Ma) banded IFs (BIFs), but with an exceptional state of preservation, allowing an unprecedented exploration of Fe-cycle dynamics in IF deposition.

Biomarker Geochemistry and Hydrocarbon Generation Potential of the Evaporites in Dongying Lacustrine Basin

2012 ◽  
Vol 616-618 ◽  
pp. 1042-1047
Author(s):  
Zhong Hong Chen
Keyword(s):  
Organic Matter ◽  
Hydrocarbon Generation ◽  
Lacustrine Basin ◽  
Hydrocarbon Generation Potential ◽  
Deep Wells ◽  
Generating Capacity ◽  
High Maturity ◽  
Different Response ◽  
Hydrocarbon Expulsion ◽  
Rock Eval

To investigate hydrocarbon potential of the evaporites, some deep wells such as Haoke-1 well and Fengshen-2 well were intensively cored, tested by TOC, Rock-Eval, and chromatography and mass spectrometry and evaluated using geochemistry of biomarker and hydrocarbon generation. High content of gammacerane and low Pr/Ph was exhibited in the evaporite system compared to the non-evaporite system. Different response of biomarkers parameters for the different sedimentary systems was exhibited, such as C19/(C19+C23) terpanes, C29/(C27+C28+C29) steranes, C24/C23 and C22/C21 tricyclic terpane. The evaporites and mud stones have the capacity to generate and expel hydrocarbons. The tested samples were mostly typeⅠand typeⅡ1 of organic matter, and their original generating capacity can reach 40 mg/g rock and 20 mg/g rock respectively. The efficiency of hydrocarbon expulsion reached 60%, but the distribution of organic matter and its generative potential was highly variable. In general, the mudstones show greater generative potential than the evaporites. High maturity severely reduced the capacity of their rocks to generate and expel petroleum.

A THERMOGRAVIMETRIC STUDY OF ORGANIC MATTER OF REPRESENTATIVE CANADIAN PODZOL SOILS

1964 ◽  
Vol 44 (1) ◽  
pp. 7-13 ◽  
Author(s):  
M. Schnitzer ◽  
R. C. Turner ◽  
I. Hoffman
Keyword(s):  
Organic Matter ◽  
High Temperature ◽  
Low Temperature ◽  
Morphological Characteristics ◽  
Inorganic Materials ◽  
Pronounced Effect ◽  
Thermogravimetric Study ◽  
Surface Materials ◽  
Organic Matter Addition ◽  
Podzol Soils

Differential thermogravimetric (DTG) curves of untreated peat, muck, and 10 different Podzol L–H materials showed peaks at approximately 100 °C (moisture), 280° (low-temperature band), and 370 to 390 °C (high-temperature band). The maxima at 280 °C were sharp and characteristic of all surface materials investigated. The DTG curves were essentially the same for all of the Podzol L–H materials investigated.The DTG curves for 12 organic matter preparations extracted from Podzol Bh, Bfh, Bhf, Bfl, and Btf horizons showed maxima at 100 °C and in the 420 to 520 °C region (high-temperature band). The peaks at 280 °C were virtually absent in these materials. This suggested differences in composition between L–H and B horizon organic matter of the Podzols studied. The variations in the positions of the high-temperature bands of the B materials were related to the morphological characteristics of these soils in the field. From this it appeared that thermogravimetry might be a useful aid in soil classification.Addition of inorganic materials did not affect the position of the low-temperature bands but had a pronounced effect on the high-temperature bands of both L–H and B organic matter. Addition of Na caused the peaks of the latter to shift to higher temperatures while addition of Al and Fe caused shifts to lower temperatures.

Sign in / Sign up

Export Citation Format

Share Document