Alignment of seismic traces is a recurring need in seismic processing and interpretation. For global alignment via static shift there are robust tools available, including cross correlation. However, another kind of alignment problem arises in applications as diverse as associating synthetic seismograms to field data, harmonizing P-wave and mode converted data, final multilevel flattening of co...

Modern seismic surveys with higher-precision numerization (24-bits A/D converters) have led to ever increasing amounts of seismic data. Management of these large datasets becomes critical, not only for transmission, but also for storage, processing and interpretation. Compression algorithms have been proposed in the geophysicists' community over the past few years as a way to e ectively manage ...

Shallow seismic reflection has seen widespread use in a variety of environmental, groundwater, and engineering applications over the last 15 years. Seismic reflection, like any other geophysical technique, has reasonably well defined limitations. Besides the well-published resolution limitation, the effectiveness of the technique is strongly dependent, and in many cases controlled, by near-surf...

in exploration seismology quality factor is widely used as a seismic attribute to identify anomalies related to attenuation, especially those caused by hydrocarbon. previous studies have indicated that seismic energy loss known as attenuation is greater for high frequency components of seismic data compared to the low frequency components. here the continuous wavelet transform is used to study ...

Inter-story drift is an important indicator of structural behaviour in performance-based seismic analysis. This paper describes the definition and contents of the inter-story drift. Existing calculation methods for harmful and harmless inter-story drift are revisited first. Their advantages and shortcomings are compared. Finally, the generalized shear deformation of region, which seems to be su...

We provide a kinematic analysis of the prestack image behaviour in the subsurface offset domain. When the medium properties are perfectly known, the image is expected to focus at the zero subsurface offset, where the incident and the scattering wavefields interact at a common point. However, kinematic artifacts are often observed in subsurface offset common-image gathers (CIGs) away from the ze...

Using common-image-point gathers (CIPs) instead of conventional image gathers for migration velocity analysis is an efficient approach for analyzing migrated images at locations that are related to geological structures. This approach reduces computational costs and may improve migration velocity analysis by acounting for diving energy. However, manually picking CIP locations is tedious and tim...

We propose 3D angle decomposition methods from elastic reverse time migration using timeand space-lag common image point gathers, time-lag common image gathers, and space-lag common image gathers computed by elastic wavefield migration. We compute time-lag common image gathers at multiple contiguous locations, instead of isolated positions as is commonly done with common image gathers. Then, we...

due to some difficulties during seismic data acquisition, like natural obstacles (high voltage electricity cable, bad coupling of geophones with the ground) some of the traces cannot be recorded. since bad traces make the final stack unclear, usually bad traces go mute while processing. the final image of the earth’s crust is highly dependent of the quality and resolution of acquired data and m...

Note to readers. What follows are drafts of six chapters of our book in progress, Seductions and Shortcuts: Fallacies in the Cognitive Economy, which is volume 3 of our omnibus work, A Practical Logic of Cognitive Systems, published by Elsevier/NorthHolland. The six chapters that appear here have been drafted as stand-alone pieces, and they have not yet been integrated into a smoothly flowing u...