Combined imaging and velocity estimation by Joint Migration Inversion

Seismic imaging projects aim to reveal the structure of the earths crust from seismic data. These projects typically include three separate processing steps, being: • attenuation of multiple reflections in the seismic data. • estimating seismic wave propagation velocities from the seismic data. • mapping the measured reflection data to the...

The double focal transformation and its application to data reconstruction

Many seismic data processing and imaging processes require densely and regularly sampled data, whereas the actual measurements are mostly irregularly and sparsely sampled. Therefore, seismic data reconstruction methods are utilised as a pre-processing step. Within the class of transformation-based reconstruction techniques, observed seismic data...

Seismic Broadband Full Waveform Inversion by shot/receiver refocusing

Full waveform inversion is a tool to obtain high-resolution property models of the subsurface from seismic data. However, the technique is computationally expens- ive and so far no multi-dimensional implementation exists to achieve a resolution that can directly be used for seismic interpretation and characterisation. In this thesis we discuss a...

Quantitative Seismic Amplitude Analysis

The Seismic Value Chain quantifies the cyclic interaction between seismic acquisition, imaging and reservoir characterization. Modern seismic innovation to address the global imbalance in hydrocarbon supply and demand requires such cyclic interaction of both feed-forward and feed-back processes. Currently, the seismic value chain paradigm is in...

Estimation of Primaries and Multiples by Sparse Inversion

Surface-related multiple reflections are often considered noise in the seismic reflection measurements. By seismic processes, such as migration and inversion, they can be mistakenly seen as primary reflections and give an erroneous image of the earth. Therefore, a method is needed to separate the multiples from the primaries. This thesis...

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...

Fourier reconstruction with sparse inversions

In seismic exploration an image of the subsurface is generated from seismic data through various data processing algorithms. When the data is not acquired on an equidistantly spaced grid, artifacts may result in the final image. Fourier reconstruction is an interpolation technique that can reduce these artifacts by generating uniformly sampled...