Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Well test analysis of naturally fractured reservoirs

Journal Article · · SPE (Society of Petroleum Engineers) Format. Eval.; (United States)
DOI:https://doi.org/10.2118/13663-PA· OSTI ID:6131549

Methods are presented for matching observed pressure data during drawdown or buildup tests. The methods, illustrated with step-by-step examples, allow calculation of fracture transmissivity, storage capacity coefficient, skin, size of matrix blocks, fracture porosity, fracture storage, and radius of investigation. The effect of matrix block shapes in the transition period has been investigated by use of a stratum model, a model made of cubes with spaces between the cubes, and a a model made of ''matchsticks'' separated by two orthogonal fracture planes. Consideration has been given to a gradient flow model as well as to unsteady-state and pseudosteady-state interporosity flow. Because many naturally fractured reservoirs are fault-related, the effect of single and intercepting sealing faults has been investigated. Even after a match of observed pressure data is obtained, there is uncertainty about calculated parameters. Consequently, a synergetic approach integrating geologic models, logs, cores, outcrops, an well testing is the only sound procedure for evaluating naturally fractured reservoirs.

Research Organization:
Servipetrol Ltd., Calgary
OSTI ID:
6131549
Journal Information:
SPE (Society of Petroleum Engineers) Format. Eval.; (United States), Journal Name: SPE (Society of Petroleum Engineers) Format. Eval.; (United States) Vol. 2:3; ISSN SFEVE
Country of Publication:
United States
Language:
English