Identification of Oil Vertical Migration Through Tectonic Fractures: A New Insight into the Oil Migration Process in the Central Ordos Basin, China

Yiwei Ren, Aiguo Wang (), Yanjun Du, Chunyu Li, Bianyang Wang, Zilong Li, Jie Wang and Jinxiang Wei
Additional contact information
Yiwei Ren: Department of Geology, Northwest University, Xi’an 710069, China
Aiguo Wang: Department of Geology, Northwest University, Xi’an 710069, China
Yanjun Du: Research Academy, Shaanxi Yanchang Petroleum (Group) Co., Ltd., Xi’an 710065, China
Chunyu Li: Engineering and Technology Department, Heilongjiang Transportation Investment Group Co., Ltd., Harbin 150028, China
Bianyang Wang: Research Academy, Shaanxi Yanchang Petroleum (Group) Co., Ltd., Xi’an 710065, China
Zilong Li: School of Geosciences, China University of Petroleum (East China), Qingdao 266580, China
Jie Wang: Department of Geology, Northwest University, Xi’an 710069, China
Jinxiang Wei: Department of Geology, Northwest University, Xi’an 710069, China

Energies, 2025, vol. 18, issue 2, 1-19

Abstract: Identifying oil migration through tectonic fractures in stable cratons is always challenging due to limited technical approaches. Here, we provide a case study showing that combined geochemical and geological analyses are a robust tool for identifying oil vertical migration through tectonic fractures. The core samples and crude oils from the Mesozoic petroleum system in the Zhijing area were investigated by an integrated analysis including petrography, biomarkers, nitrogen compounds, and spatial distribution. The tectonic fractures in the Yanchang Formation (YcF) are more developed compared to the Yan’an Formation (YaF), influencing oil migration patterns and reservoir distribution. Eighty-one percent of the tectonic fractures are filled with calcite cement, while only two percent of the tectonic fractures contain solid bitumen. The YaF and YcF oils originating from the same oil source are at the same maturity level. However, the YaF oils exhibit disordered nC 18- distribution and “mismatches” at n -undecane and a decrease in toluene/ n -heptane ratios, which resulted from the phase fractionation caused by the vertical migration through tectonic fractures. The spatial distributions of 1/4-MC, 1,8/2,7-DMC, and Ts/Tm values in the YaF oils are irregular. Furthermore, the areas occupied by the YaF oil reservoirs exhibit an absence of YcFs, and vice versa. These distribution patterns can be explained by oil vertical migration through tectonic fractures. A series of pieces of evidence indicates that the oils migrated vertically through tectonic fractures to the YaF. This study offers new insights into the oil migration process within the Mesozoic petroleum system of the central Ordos Basin and serves as guidance for identifying oil migration through tectonic fractures in stable cratons.

Keywords: fractures; vertical migration; Ordos Basin; Zhijing area; Yan’an Formation; Yanchang Formation (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2025
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/18/2/283/pdf (application/pdf)
https://www.mdpi.com/1996-1073/18/2/283/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:18:y:2025:i:2:p:283-:d:1564241

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().