Whole-Core Analysis for Effective Characterization of Inter-Well Permeability from a Horizontal Well

Abdulla H. Bu Ali¹*, Mehdi M. Honarpour², Syed M. Tariq¹, and Nizar F. Djabbarah^3
1Zadco
²ExxonMobil Upstream Research, USA
³ExxonMobil, USA
*[email protected]

Whole-core analysis is critical for characterizing porosity and directional permeability in heterogeneous, fractured and/or anisotropic rocks. Whole-core measurements are essential because small-scale heterogeneity may not be appropriately represented in plug measurements. Additionally, for characterization of multi-phase flow properties (special core analysis) in heterogeneous rocks, whole-core analysis is required. Special whole-core analyses are not frequently conducted on whole cores because of experimental difficulties, such as establishing representative water saturation. It is rare that cores are taken and whole-core analysis is conducted from a horizontal well in a carbonate reservoir. The objectives and results of this presentation are: (1) show permeability variability at inter-well scale from a horizontal well in a carbonate reservoir in Abu Dhabi. (2) Compare vertical permeability in whole cores obtained from a horizontal well to vertical permeability obtained from an adjacent vertical core. (3) Analyze gas-oil relative permeability measurements conducted on whole cores. These were modeled and compared with gas-oil relative permeability data at plug scale. Klinkenberg-corrected permeability on whole cores under reservoir net-confining stress was measured and the results were compared with plug analysis from the same interval. (4) Demonstrate quality-control and data-analysis procedures for whole-core analysis. Uncertainty in routine and special whole-core analysis data were quantified and quality-control and data-analysis procedure are presented.

AAPG Search and Discovery Article #90077©2008 GEO 2008 Middle East Conference and Exhibition, Manama, Bahrain