Quantitative prediction of structural fractures in the Paleocene lower Wenchang formation reservoir of the Lufeng Depression

Abstract

Currently, the lower Paleogene Wenchang formation in the Lufeng Depression is the primary focus of reservoir development. The structural fractures that have formed inside of it not only serve as the principal path for oil migration, but also as oil storage space. As a result, the distribution features of structural fractures are crucial for future petroleum exploration and development in the Lufeng Depression. At the same time, with the quantity of conventional reservoirs in the Lufeng Depression on the decline, it is critical to determine the fracture distribution criteria for deep unconventional reservoirs. In this work, the lower Paleogene Wenchang formation in the Lufeng Depression is used as the research stratum. Then, based on existing logging data for the research region, the distinct physical properties of different rock kinds are calculated. The simulation results of the paleotectonic stress field in the study area using the finite element numerical simulation software ANSYS show that the high-value areas of maximum principal stress are the high-value areas of the uplift belt and low uplift, and the areas with low maximum principal stress are the low-value areas of Lufeng 13 Sag and the gentle slope belt in the north of Lufeng middle-low uplift. The fracture density is quantitatively predicted after the stress field simulation, which shows good agreement between the anticipated and actual observed values, and an average error of 13.61%. The predicted findings may provide new ideas for future petroleum exploration.

cited as: Li, H., Yu, F., Wang, M., Wang, Y., Liu, Y. Quantitative prediction of structural fractures in the Paleocene lower Wenchang formation reservoir of the Lufeng Depression. Advances in Geo-Energy Research, 2022, 6(5): 375-387. https://doi.org/10.46690/ager.2022.05.03

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