Quantitative imaging of fractures around a borehole using linear slip theory and elastic least-squares migration

Single-well reflection imaging using sonic logging data successfully locates fine-scale structures around a borehole including fractures. In order to achieve accurate and quantitative estimation of fracture properties with high resolution, we propose to couple least-squares migration with linear slip theory. The proposed least-squares...

A parametric level-set approach for seismic full-waveform inversion

<br/>In seismic exploration, the delineation of large bodies with hard exterior contrasts but nearly constant interior properties is a challenge. Examples include salt diapirs, salt slabs, anhydrite or basalt layers. Salt geometries are of particular interest because they often have hydrocarbon reservoirs on their sides or underneath. This...

Laboratory estimation of fracture compliance of a fluid-filled fracture using AVO response of a nonwelded interface

We explore the potential of multi-angle AVO inversion of P-P and P-S reflections from a fracture to estimate fracture proper- ties. Although AVO analysis of welded interface like geologi- cal layer boundaries is common, the use of AVO variations for nonwelded boundaries like fractures is yet to be investigated. We conduct laboratory experiments...

Multi-objective full waveform inversion in the absence of low frequencies

Least-squares inversion of seismic reflection waveforms can reconstruct remarkably detailed models of the Earth’s subsurface. However, the cycle-skipping associated with the highfrequency waveforms are responsible for spurious local minima in its objective function. Therefore, it is often difficult for descent methods to converge to the true...

Ray-based stochastic inversion of pre-stack seismic data for improved reservoir characterisation

To estimate rock and pore-fluid properties of oil and gas reservoirs in the subsurface, techniques can be used that invert seismic data. Hereby, the detailed information about the reservoir that is available at well locations, such as the thickness and porosity of individual layers, is extrapolated to all locations in the reservoir on the basis...