International Journal of

ADVANCED AND APPLIED SCIENCES

EISSN: 2313-3724, Print ISSN: 2313-626X

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 Volume 13, Issue 1 (January 2026), Pages: 125-133

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 Original Research Paper

Effect of organic matter on porosity changes in thermally treated oil shale based on the differential T 2 (DT 2) spectrum

 Author(s): 

 Congming Ma, Bei Qiu, Lifeng Fan *

 Affiliation(s):

 College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, China

 Full text

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 * Corresponding Author. 

   Corresponding author's ORCID profile:  https://orcid.org/0000-0002-7744-692X

 Digital Object Identifier (DOI)

  https://doi.org/10.21833/ijaas.2026.01.013

 Abstract

Evaluating the porosity of oil shale at high temperatures is essential for resource exploration and development. However, the organic matter in oil shale rock, which is naturally rich in hydrogen, complicates assessments made using nuclear magnetic resonance (NMR) technology. In this paper, the differential T 2 (DT 2) spectrum method is introduced to correct the effects of organic matter on porosity measurements using nuclear magnetic resonance (NMR). Firstly, the T 2 spectrum was obtained for both dry oil shale rock, which contains organic matter, and saturated oil shale rock, which contains both organic matter and pore water. Secondly, the DT 2 spectrum of pore water in oil shale rock was obtained to determine the porosity of the oil shale rock containing organic matter. Finally, the impact of organic matter on the variation in porosity of oil shale rock as temperature increases was discussed. The results indicate that the porosity of oil shale rock increases slightly when the temperature is below 400 °C and rises significantly between 400 °C and 800 °C. The rate of porosity changes in oil shale rock increases gradually between 100 °C and 400 °C. The rate of porosity change in oil shale rock increases significantly and then decreases between 400 °C and 800 °C. There is a specific temperature at which the porosity changes of oil shale transitions from rapid to gradual.

 © 2025 The Authors. Published by IASE.

 This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/).

 Keywords

 Oil shale, Organic matter, Nuclear magnetic resonance (NMR), High-temperature treatment, Microstructural changes

 Article history

 Received 14 May 2025, Received in revised form 26 October 2025, Accepted 24 December 2025

 Acknowledgment

No Acknowledgment. 

 Compliance with ethical standards

 Conflict of interest: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

 Citation:

 Ma C, Qiu B, and Fan L (2026). Effect of organic matter on porosity changes in thermally treated oil shale based on the differential T 2 (DT 2) spectrum. International Journal of Advanced and Applied Sciences, 13(1): 125-133

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 Figures

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