A New Indicator of the Maturity of Organic Matter from Domanik Deposits

2021 ◽  
Vol 62 (2) ◽  
pp. 149-156
Author(s):  
N.S. Burdel’naya ◽  
D.A. Bushnev
Keyword(s):  
Organic Matter ◽  
Late Devonian ◽  
Aromatic Fraction ◽  
Thermal Maturation

Abstract —Study of the aromatic fraction of Late Devonian oils and organic matter from domanik deposits of the Timan–Pechora petroleum province has revealed compounds whose proportion depends on the degree of OM transformation, namely, 1,1,7,8-tetramethyl-1,2,3,4-tetrahydrophenanthrene (1,1,7,8-TMHP) and 1,2,8-trimethylphenanthrene (1,2,8-TMP). It has been established that 1,1,7,8-TMHP dominates over 1,2,8-TMP in the immature OM; as the thermal maturation of OM increases, 1,2,8-TMP begins to prevail. The same pattern is observed for the Late Devonian oils. An increase in the ratio of 1,2,8-TMP to 1,1,7,8-TMHP with the growing thermal maturation of OM and the transition of one compound into another permit using this ratio as an additional indicator of OM maturity in domanik rocks.

scholarly journals Diamondoids and Thiadiamondoids Generated From Hydrothermal Pyrolysis of Crude Oil and TSR Experiments

2021 ◽  
Author(s):  
Yanyan Peng ◽  
Chunfang Cai ◽  
Chenchen Fang ◽  
Liangliang Wu ◽  
Jinzhong Liu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Crude Oil ◽  
Elevated Temperatures ◽  
Source Rocks ◽  
Chemical Alteration ◽  
Thermal Maturation ◽  
Direct Reactions ◽  
New Generation ◽  
Oil Cracking ◽  
New Formula

Abstract Diamondoid compounds are widely used to reflect thermal maturation of high mature source rocks or oils and oil cracking extents. However, diamondoids and thiadiamondoids were demonstrated to have newly been generated and decomposed in our hydrothermal pyrolysis of crude oil and TSR experiments. Our results show that adamantanes and diamantanes are generated primarily within the maturity range 0.48–2.1% and 1.2–3.0% EasyRo, respectively. Their formation is enhanced and the decomposition of diamantanes obviously lags behind at elevated temperatures compared with anhydrous experiments. MDI, EAI, DMAI-1, DMDI-2 may serve as reliable maturity proxies at > ca.1.0% EasyRo, and other isomerization indices (TMAI-1, TMAI-2 and DMAI-2) are effective for the highly mature organic matter at EasyRo > 2.0%. The extent of oil cracking (EOC) calculated from the broadly used 3-+4-MD method (Dahl et al., 1999) is proven to overestimate, especially for highly cracked samples due to the new generation of 3-+4-MD. Still, it can be corrected using a new formula at <3.0% EasyRo. Other diamondoid-related indices (e.g. EAI, DMDI-2, As/Ds, MAs/MDs, DMAs/DMDs, and DMAs/MDs) can also be used to estimate EOC. However, these indices cannot be applied to TSR-altered petroleum. TSR is experimentally confirmed to generate diamantanes and thiaadmantanes at 1.81% EasyRo via direct reactions of reduced S species with hydrocarbons and accelerate the decomposition of diamantanes at > 3.0% EasyRo compared with thermal chemical alteration (TCA).

Impact of thermal maturation on nano-scale elastic properties of organic matter in shales

2016 ◽  
Vol 70 ◽  
pp. 175-184 ◽  
Author(s):  
Simon Emmanuel ◽  
Moshe Eliyahu ◽  
Ruarri J. Day-Stirrat ◽  
Ronny Hofmann ◽  
Calum I. Macaulay
Keyword(s):  
Organic Matter ◽  
Elastic Properties ◽  
Thermal Maturation ◽  
Nano Scale

scholarly journals Effect of organic matter composition on source rock porosity during confined anhydrous thermal maturation: Example of Kimmeridge-clay mudstones

2019 ◽  
Vol 212 ◽  
pp. 103236 ◽  
Author(s):  
Amélie Cavelan ◽  
Mohammed Boussafir ◽  
Claude Le Milbeau ◽  
Olivier Rozenbaum ◽  
Fatima Laggoun-Défarge
Keyword(s):  
Organic Matter ◽  
Source Rock ◽  
Organic Matter Composition ◽  
Thermal Maturation ◽  
Rock Porosity
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