Fracture intensity and associated variability: A new methodology for 3D digital outcrop model analysis of carbonate reservoirs

Abstract
The presence of hydraulically conductive fracture networks fundamentally affects subsurface fluid flow, the recovery factor and productivity in hydrocarbon carbonate reservoirs. However, methods to directly detect and map the 3D distribution and intensity of fracture networks in the subsurface is difficult. We present a new workflow and methodologies to overcome these limitations utilizing 3D digital photogrammetry on a prominent outcrop of the Late Jurassic (Kimmeridgian) Jubaila Formation near Wadi Laban (Riyadh, Saudi Arabia) as an example. Subsurface equivalents of the Upper Jubaila Formation host major oil and gas accumulations on the Arabian platform. The workflow includes mapping of fracture intensity, distribution and orientation along a 750 m long exposure transect using a high-resolution 3D Digital Outcrop Model (DOM). Results show two main fracture trends, which were E-W and NNE-SSW oriented. The techniques enable computation of fracture intensity directly on the 3D DOM, and quantification of lateral and vertical fracture intensity variability and fracture corridors. The new methodology of 3D DOM analysis, provides a reliable characterization of fractures and fracture intensity that are critical for enhancing 3D reservoir models.

Citation
Panara, Y., Chandra, V., Finkbeiner, T., Petrovic, A., Zühlke, R., Khanna, P., & Vahrenkamp, V. (2023). Fracture intensity and associated variability: A new methodology for 3D digital outcrop model analysis of carbonate reservoirs. Marine and Petroleum Geology, 106532. https://doi.org/10.1016/j.marpetgeo.2023.106532

Acknowledgements
The project was funded by King Abdullah University of Science and Technology through baseline support to V. Vahrenkamp and by an ARAMCO industrial grant to V. Vahrenkamp. We are grateful to Gabrielle Abelskamp for the non-technical review of the manuscript.

Publisher
Elsevier BV

Journal
Marine and Petroleum Geology

DOI
10.1016/j.marpetgeo.2023.106532

Additional Links
https://linkinghub.elsevier.com/retrieve/pii/S0264817223004385