Characterizing natural fractures productivity in tight gas Reservoirs
MetadataShow full item record
This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.
The final publication is available at: http://www.springerlink.com
Tight formations normally have production problems mainly due to very low matrix permeability and various forms of formation damage that occur during drilling completion and production operation. In naturally fractured tight gas reservoirs, gas is mainly stored in the rock matrix with very low permeability, and the natural fractures have the main contribution on total gas production. Therefore, identifying natural fractures characteristics in the tight formations is essential for well productivity evaluations. Well testing and logging are the common tools employed to evaluate well productivity. Use of image log can provide fracture static parameters, and welltest analysis can provide data related to reservoir dynamic parameters. However, due to the low matrix permeability and complexity of the formation in naturally fractured tight gas reservoirs, welltest data are affected by long wellbore storage effect that masks the reservoir response to pressure change, and it may fail to provide dual-porosity dual-permeability models dynamic characteristics such as fracture permeability, fracture storativity ratio and interporosity flow coefficient.Therefore, application of welltest and image log data in naturally fractured tight gas reservoirs for meaningful results may not be well understood and the data may be difficult to interpret. This paper presents the estimation of fracture permeability in naturally fractured tight gas formations, by integration of welltest analysis results and image log data based on Kazemi’s simplified model. Reservoir simulation of dual-porosity and dual-permeability systems and sensitivity analysis are performed for different matrix and fracture parameters to understand the relationship between natural fractures parameters with welltest permeability. The simulation results confirmed reliability of the proposed correlation for fracture permeability estimation. A field example is also shown to demonstrate application of welltest analysis and image log data processing results in estimating average permeability of natural fractures for the tight gas reservoir.
Showing items related by title, author, creator and subject.
Stress Anisotropy, Long-Term Reservoir Flow Regimes and Production Performance in Tight Gas ReservoirsBahrami, H.; Rezaee, M. Reza; Asadi, Mohammad Sadegh (2010)Tight gas reservoirs normally have production problems due to very low matrix permeability and different damagemechanisms during drilling, completion and stimulation. Tight reservoirs need advanced drilling and completion ...
Bahrami, Hassan (2012)Production at economical rates from tight gas reservoirs in general is very challenging not only due to the very low intrinsic permeability but also as a consequence of several different forms of formation damage that can ...
Estimating cleat characteristics in reservoir simulation models of coal seam gas reservoirs using welltest analysisBahrami, N.; Byfield, R.; Hossain, Mofazzal; Chitgar, A.; Wong, J. (2015)Copyright 2015 Society of Petroleum Engineers.Coal Seam Gas reservoirs are naturally fractured and the flow of fluid throughout the coal occurs by diffusion through the coal matrix and then via the cleats (network of ...