A methodology to detect and locate low-permeability faults to reduce the risk of inducing seismicity of fluid injection operations in deep saline formations. (April 2017)

• Record Type: Journal Article
• Authors: Vilarrasa, Victor; Bustarret, Gil; Laloui, Lyesse; Zeidouni, Mehdi
• Is Part Of: International journal of greenhouse gas control. Volume 59(2017)
• Page Start: 110
• Page End: 122
• Publication Date: 2017-04
• Subjects: Fluid injection -- Pressure buildup -- Diagnostic plots -- Induced seismicity -- Dimensional analysis -- Numerical models; Greenhouse gases -- Environmental aspects -- Periodicals; Air -- Purification -- Technological innovations -- Periodicals; Gaz à effet de serre -- Périodiques; Gaz à effet de serre -- Réduction -- Périodiques; Air -- Purification -- Technological innovations; Greenhouse gases -- Environmental aspects; Periodicals; 363.73874605
• DOI: 10.1016/j.ijggc.2017.02.010
• Languages: English
• ISSNs: 1750-5836

Abstract

Highlights: A methodology to detect and locate low-permeability faults is proposed. Fault detection is crucial to anticipate felt induced seismicity. The methodology is useful for reducing the risk of inducing felt seismic events. The applicability of the methodology is illustrated for a horizontal well. The methodology can be extended to other geological and geometrical settings. Abstract: Fluid injection in the subsurface has significantly increased over the last decades. Since fluid injection causes pressure buildup, reducing effective stresses, shear failure conditions may eventually occur, inducing microseismic and seismic events. Anticipating felt induced earthquakes that may be triggered in undetected faults is crucial for the success of fluid injection projects. We propose a methodology to detect and locate such low-permeability faults to reduce the risk of inducing felt seismic events. The methodology consists in using diagnostic plots to identify the divergence time between the logarithmic derivative of overpressure evolution measured in the field and the one that would correspond to an aquifer including the previously identified heterogeneities. We apply the proposed methodology to water and CO2 injection through a horizontal well in a confined aquifer that has faults parallel to the well. We numerically obtain type curves that allow locating low-permeability faults once the divergence time is determined from the logarithmic derivative of overpressure for both water and CO2 injection. Furthermore, we illustrate how to apply the methodology to detect multiple low-permeability faults. To perform a proper pressure management based on fault stability analysis to minimize the risk of inducing felt seismic events, the proposed methodology should be complemented with other multidisciplinary tools. This methodology can be extended to other geological settings and be used in several fluid injection applications.