Experimental identification of the transition from elasticity to inelasticity from ultrasonic attenuation analyses

The transition from recoverable elastic to permanent inelastic deformation is marked by the onset of fracturing in the brittle field. Detection of this transition in materials is crucial to predict imminent failure/fracturing. We have<br/>used an ultrasonic pulse transmission method to record the change in waveform across this transition during...

Signature of seismic wave attenuation during fracture network formation

Ultrasonic velocity and attenuation anisotropy of shales, Whitby, United Kingdom

We have conducted ultrasonic experiments, between 0.3 and 1 MHz, to measure velocity and attenuation (Q?1) anisotropy of P- and S-waves in dry Whitby Mudstone samples as a function of stress. We found the degree of anisotropy to be as large as 70% for velocity and attenuation. The sensitivity of P-wave anisotropy change with applied stress is...

Fluid mobility in reservoir rocks from integrated VSP and openhole data

In this study, we first estimate seismic velocity and attenuation dispersion from a comprehensive zero-offset vertical seismic profile (VSP) data acquired in China. These results, combined with openhole data acquired at the same location, provide experimental evidence that the seismic attenuation in rocks is dominated by a fluid-flow mechanism....

Flow Properties in Saturated Soils from Differing Behaviour of Dispersive Seismic Velocity and Attenuation

A careful look into the pertinent models of poroelasticity reveals that in water-saturated sediments or soils, the seismic (P and S wave) velocity dispersion and attenuation in the low field-seismic frequency band (20-200 Hz) have a contrasting behaviour in the porosity-permeability domain.Taking advantage of this nearly orthogonal behaviour, a...

Contrasting behavior between dispersive seismic velocity and attenuation: Advantages in subsoil characterization

A careful look into the pertinent models of poroelasticity reveals that in water-saturated sediments or soils, the seismic (P and S wave) velocity dispersion and attenuation in the low field-seismic frequency band (20–200 Hz) have a contrasting behavior in the porosity-permeability domain. Taking advantage of this nearly orthogonal behavior, a...