TY - CONF
T1 - Pressure-transient-analysis of horizontal wells with transverse, finite-conductivity fractures
AU - Al-Kobaisi, M.
AU - Ozkan, E.
AU - Kazemi, H.
AU - Ramirez, B.
N1 - Funding Information:
Portions of this work has been taken from the MSc Thesis of Mohammed Al-Kobaisi to fulfill the requirement for the MSc degree in Petroleum Engineering at the Colorado School of Mines. The financial support of ADNOC for Mr. Al-Kobaisi's graduate study is gratefully acknowledged. This work has been conducted under Marathon Center of Excellence for Reservoir Studies at Colorado School of Mines.
PY - 2006
Y1 - 2006
N2 - This paper discusses the analysis of pressure-transient responses of horizontal wells intercepting finite-conductivity transverse fractures. We use a hybrid, numerical-analytical model to simulate the impact of the fracture properties on the early-time flow regimes and pressure transient characteristics of fractured horizontal wells. It is shown that the fracture geometry and well location strongly influence the flow convergence in a horizontal-well fracture and lead to early-time flow regimes different from vertical-well fractures. Accordingly, appropriate pressure-transient models and analysis procedures should be used to determine fracture properties. We present straight-line analysis equations for radial-linear and pseudo-bilinear flow regimes for circular and rectangular fractures, respectively. We also bring the conventional fracture half-length and conductivity concepts into perspective and question the assumption that the properties estimated from pressure-transient tests of horizontal-well may be taken as effective properties when fractures are not rectangular. We show that flow convergence toward the wellbore may increase non-Darcy flow within the fracture. If the additional pressure drop because of flow choking and non-Darcy flow is not taken into account, pressure-transient tests indicate smaller effective conductivity or fracture size. Because this additional pressure-drop is flow rate dependent, the estimated effective fracture properties are not useful for performance prediction purposes.
AB - This paper discusses the analysis of pressure-transient responses of horizontal wells intercepting finite-conductivity transverse fractures. We use a hybrid, numerical-analytical model to simulate the impact of the fracture properties on the early-time flow regimes and pressure transient characteristics of fractured horizontal wells. It is shown that the fracture geometry and well location strongly influence the flow convergence in a horizontal-well fracture and lead to early-time flow regimes different from vertical-well fractures. Accordingly, appropriate pressure-transient models and analysis procedures should be used to determine fracture properties. We present straight-line analysis equations for radial-linear and pseudo-bilinear flow regimes for circular and rectangular fractures, respectively. We also bring the conventional fracture half-length and conductivity concepts into perspective and question the assumption that the properties estimated from pressure-transient tests of horizontal-well may be taken as effective properties when fractures are not rectangular. We show that flow convergence toward the wellbore may increase non-Darcy flow within the fracture. If the additional pressure drop because of flow choking and non-Darcy flow is not taken into account, pressure-transient tests indicate smaller effective conductivity or fracture size. Because this additional pressure-drop is flow rate dependent, the estimated effective fracture properties are not useful for performance prediction purposes.
UR - http://www.scopus.com/inward/record.url?scp=85085405767&partnerID=8YFLogxK
U2 - 10.2118/2006-162
DO - 10.2118/2006-162
M3 - Paper
AN - SCOPUS:85085405767
T2 - Canadian International Petroleum Conference, CIPC 2006
Y2 - 13 June 2006 through 15 June 2006
ER -