3-D transport and acoustic properties of Fontainebleau sandstone during true-triaxial deformation experiments

Abstract Fontainebleau sandstone specimens have been tested in a true-triaxial geophysical imaging cell under hydrostatic (σ1=σ2=σ3), traditional triaxial (σ1=σ2>σ3) and true-triaxial (σ1> σ2>σ3) stress regimes. The research objectives are to recognize the effect of various stress ratios σ2/σ3 under varying magnitudes of σ2 and σ3 on 3-D stress–strain responses, 3-D transport, 3-D ultrasonic wave velocities, and acoustic emission properties. Comparison of the variation of 3-D directional permeability between the specimens shows that higher magnitude of σ3 and σ2 disrupts the 3-D interconnectivity of the pore spaces and intergranular cracks, irrespective of the magnitude of applied stress ratio σ2/σ3. The observed permeability anisotropy between the two specimens is a function of inherent oriented pores and cracks, stress ratio σ2/σ3 and the magnitude of applied σ3 and σ2 stresses. Temporal and spatial evolution of the AE hypocenter locations combined with the examination of micro-CT and thin section images shows the timely development of polymodal fault systems during peak to post-peak stresses and validates the development of the source mechanism inferred from the acoustic emission events.

[1]  Philip G. Meredith,et al.  Laboratory Simulation of Volcano Seismicity , 2008, Science.

[2]  Y. Guéguen,et al.  Elastic wave velocities and permeability of cracked rocks , 2003 .

[3]  Colin M. Sayers,et al.  Stress-induced ultrasonic anisotrophy in Berea sandstone , 1990 .

[4]  V. Rasouli.  A true triaxial stress cell (TTSC) used for simulations of real field operations in the lab , 2012 .

[5]  Kiyoo Mogi,et al.  Effect of the triaxial stress system on the failure of dolomite and limestone , 1971 .

[6]  M. S. King.  Elastic wave propagation in and permeability for rocks with multiple parallel fractures , 2002 .

[7]  R. Madariaga,et al.  From Sub-Rayleigh to Supershear Ruptures During Stick-Slip Experiments on Crustal Rocks , 2013, Science.

[8]  David J. Sanderson,et al.  EVALUATION OF THE 2-D PERMEABILITY TENSOR FOR FRACTURED ROCK MASSES , 1996 .

[9]  R. Jeanloz,et al.  Introduction to the physics of rocks , 1994 .

[10]  K. Mogi,et al.  Flow and fracture of rocks under general triaxial compression , 1981 .

[11]  M. Zamora,et al.  Permeability anisotropy and its relations with porous medium structure , 2008 .

[12]  Tomoya Niwa,et al.  Acoustic emission monitoring of hydraulic fracturing laboratory experiment with supercritical and liquid CO2 , 2012 .

[13]  J. Dieterich,et al.  Faulting of rocks in three-dimensional strain fields I. Failure of rocks in polyaxial, servo-control experiments , 1983 .

[14]  Steven D. Glaser,et al.  Micromechanics of asperity rupture during laboratory stick slip experiments , 2011 .

[15]  J. B. Walsh,et al.  Permeability of granite under high pressure , 1968 .

[16]  R. P. Young,et al.  Premonitory acoustic emissions and stick‐slip in natural and smooth‐faulted Westerly granite , 2009 .

[17]  Kiyoo Mogi,et al.  Fracture and flow of rocks under high triaxial compression , 1971 .

[18]  S. Stanchits,et al.  Initiation and Propagation of Compaction Bands in Dry and Wet Bentheim Sandstone , 2009 .

[19]  Bezalel C. Haimson,et al.  A new true triaxial cell for testing mechanical properties of rock, and its use to determine rock strength and deformability of Westerly granite , 2000 .

[20]  A. Schwartzkopff,et al.  Design and fabrication of a low cost true triaxial cell for testing multiple size specimens , 2012 .

[21]  Kiyoo Mogi,et al.  DILATANCY OF ROCKS UNDER GENERAL TRIAXIAL STRESS STATES WITH SPECIAL REFERENCE TO EARTHQUAKE PRECURSORS , 1977 .

[22]  M. S. King,et al.  Acoustic emissions associated with the formation of fracture sets in sandstone under polyaxial stress conditions ‡ , 2012 .

[23]  Xinglin Lei,et al.  Detailed analysis of acoustic emission activity during catastrophic fracture of faults in rock , 2004 .

[24]  Bernard Budiansky,et al.  Seismic velocities in dry and saturated cracked solids , 1974 .

[25]  Jonny Rutqvist,et al.  Stress-dependent permeability of fractured rock masses: A numerical study , 2004 .

[26]  Y. Takei.  Constitutive mechanical relations of solid-liquid composites in terms of grain-boundary contiguity , 1998 .

[27]  H. Koide,et al.  Effect of the Intermediate Principal Stress On Strength And Deformation Behavior of Sedimentary Rocks At the Depth Shallower Than 2000 M , 1989 .

[28]  Kiyoo Mogi,et al.  Experimental Rock Mechanics , 2006 .

[29]  Yasuko Takei,et al.  Effect of pore geometry on VP/VS: From equilibrium geometry to crack , 2002 .

[30]  D. Lockner.  The role of acoustic emission in the study of rock fracture , 1993 .

[31]  Bezalel C. Haimson,et al.  Brittle fracture in two crystalline rocks under true triaxial compressive stresses , 2005, Geological Society, London, Special Publications.

[32]  A. Aydin,et al.  Number and orientation of fault sets in the field and in experiments , 1982 .

[33]  Kiyoo Mogi,et al.  Effect of the intermediate principal stress on rock failure , 1967 .

[34]  Steven D. Glaser,et al.  Acoustic Emission Sensor Calibration for Absolute Source Measurements , 2012 .

[35]  Carl H. Sondergeld,et al.  Surface deformation, crack formation, and acoustic velocity changes in pyrophyllite under polyaxial loading , 1981 .

[36]  Bernard Budiansky,et al.  Viscoelastic properties of fluid-saturated cracked solids , 1977 .

[37]  Bezalel C. Haimson,et al.  True triaxial strength of the KTB amphibolite under borehole wall conditions and its use to estimate the maximum horizontal in situ stress , 2002 .

[38]  Kiyoo Mogi,et al.  Effect of the triaxial stress system on fracture and flow of rocks , 1972 .

[39]  S. Stanchits,et al.  Source analysis of acoustic emissions in Aue granite cores under symmetric and asymmetric compressive loads , 1998 .