Angle-gather migration creates seismic images for different reflection angles at the reflector. We formulate an angle-gather time migration algorithm and study its properties. The algorithm serves as an educational introduction to the angle gather concept. It also looks attractive as a practical alternative to conventional common-offset time migration both for velocity analysis and for AVO/AVA ...

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Gas-hydrates are crystalline form of water and methane that form at high pressure and low temperature. They have attracted the global attention due to their wide-spread occurrences in the permafrost and outer continental margins; potential as major energy resources; role in climate change etc. It is estimated that the carbon in gas-hydrates is two times the carbon content in fossil fuel reserve...

Azimuthally-dependent P-wave AVO (amplitude variation with offset) responses can be related to open fracture orientation and have been suggested as a geophysical tool to identify fracture orientation in fractured oil and gas reservoirs. A field experiment recently conducted over a fractured reservoir in the Barinas Basin (Venezuela) provides data for an excellent test of this approach. Three li...

BACKGROUND Established methods to determine asynchrony suffer from high intra- and interobserver variability and failed to improve patient selection for cardiac resynchronization therapy (CRT). Thus, there is a need for easy and robust approaches to reliably assess cardiac asynchrony. METHODS AND RESULTS We performed echocardiography in 100 healthy subjects and 33 patients with left bundle br...

Estimates Calculating Algorithms have a long story of application to recognition problems. Furthermore they have formed a basis for algebraic recognition theory. Yet use of ECA polynomials was limited to theoretical reasoning because of complexity of their construction and optimization. The new recognition method “AVOpolynom” based upon ECA polynomial of simple structure is described.

Rock physical model and amplitude variation with offset (AVO) patterns considering the content of organic matter composition minerals have a wider significance for guiding identification prediction mud-rich source rock. A rock is proposed describing elastic properties kerogen in different maturity stages. The builds an intrinsic connection between parameters rock, thereby providing theoretical ...

The ability to create subsurface images whose amplitudes are proportional the elastic wavefield variations recorded within seismic data as a function of reflection angle is fundamental for performing accurate amplitude-variation-with-offset (AVO) analysis and inversion. A process that generates such commonly referred true-amplitude migration. We have determined how extended subsurface-offset im...