Nitrogen isotopes of marine oils in the Tarim Basin, China: Implications for the origin of organic matters and the paleoenvironment

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389005%3A_____%2F24%3A00604109" target="_blank" >RIV/61389005:_____/24:00604109 - isvavai.cz</a>

Result on the web

<a href="https://www.sciencedirect.com/science/article/pii/S199582262400133X" target="_blank" >https://www.sciencedirect.com/science/article/pii/S199582262400133X</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.petsci.2024.05.016" target="_blank" >10.1016/j.petsci.2024.05.016</a>

Result language

angličtina

Original language name

Nitrogen isotopes of marine oils in the Tarim Basin, China: Implications for the origin of organic matters and the paleoenvironment

Original language description

Nitrogen isotope compositions (S15N) of sedimentary rocks are usually used to reconstruct the paleoenvironment and nitrogen (N) biogeochemical cycle. The S 15 N values of crude oils inherit the characteristics of relevant source rocks and can well reflect the information of hydrocarbon-forming organisms and environment in ancient water column. However, studies on the S 15 N of crude oils are limited due to the low N content. In this study, a new efficient method is applied to the marine oils from the Bashituo (BST) and Halahatang (HLHT) areas of the Tarim Basin to obtain the nitrogenous components (i.e., nonhydrocarbons and asphaltenes) for the achievement of N concentration. The carbon and nitrogen isotopes of these components and the biomarkers of oils were measured. The S 15 N values in asphaltenes ( S 15 N Asp ) are significantly heavier than those in nonhydrocarbons ( S 15 N NSOs ) in these oils, which are attributed to the potential directional N transfer and kinetic isotope fractionation during the thermal evolution of organic matters (OM). The S 15 N Asp values have significant correlations with OM origin associated parameters and weak correlations with environmental parameters, suggesting that the difference in S 15 N Asp values is mainly resulted from biological source rather than redox conditions. The S 15 N NSOs values have a closer relationship with the redox condition than biological characteristics, indicating that they have a good response to paleoenvironmental variation in the water column, which is not completely overprinted by the difference of OM origin. Different redox conditions give rise to distinct nitrogen cycles, resulting in various S 15 N values. Anammox occurs in the water column of the Early Cambrian dominated by physically stratified conditions with significant isotope fractionation, resulting in relatively heavier S 15 N of OM in the BST area. In the Middle-Late Ordovician period, the limited suboxic zone leads to an insignificant positive bias of S 15 N caused by partial denitrification in the HLHT oils. The evaluation of S 15 N in nitrogenous fractions enables a more comprehensive reconstruction of N cycle for ancient oceans.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10505 - Geology

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2024

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Petroleum Science

ISSN

1672-5107

e-ISSN

1995-8226

Volume of the periodical

21

Issue of the periodical within the volume

6

Country of publishing house

CN - CHINA

Number of pages

14

Pages from-to

3692-3705

UT code for WoS article

001392236400001

EID of the result in the Scopus database

2-s2.0-85211123261