the direct way to access the petrophysical property of hydrocarbon reservoir is based on well data but due to its high cost, the seismic data has been used to obtain these parameters. for this purpose, many different methods are available and each has its own advantages and limitations. from these methods the seismic inversion is the best tool to study the reservoir characterization. the outcom...

Best-basis searching algorithm based on binary (in general, M-ary) segmentation was constructed by Coifman and Wickerhauser in 1992 [1] (IEEE Trans. on Information Theory, 38, 713-718). However, there are several problems with the binary scheme. First, the binary segmentation is inflexible in grouping signals along the axis. Secondly, the binary-based segmentation method is very sensitive to ti...

Seismic data comprise many traces that provide a spatiotemporal sampling of the reflected wavefield. However, such informationmay suffer from ambient and random noise during acquisition, which could possibly limit the use of seismic data in reservoir locating. Traditionally, fixed transforms are used to separate the noise from the data by exploiting their different characteristics in a transfor...

We present a method for estimating seismic attenuation based on frequency shift data. In most natural materials, seismic attenuation increases with frequency. The high-frequency components of the seismic signal are attenuated more rapidly than the low-frequency components as waves propagate. As a result, the centroid of the signal’s spectrum experiences a downshift during propagation. Under the...

Existence of gas-hydrates in the marine sediments elevates the velocity of seismic waves, whereas even a small amount of underlying free-gas decreases the seismic velocity considerably. These changes in velocities can be used for the assessment of gas-hydrates. The traveltime inversion is an effective method to derive a 2-D velocity structure from the seismic data. We have applied the method to...

The cataclysmic 18 May 1980 eruption at Mount St. Helens was preceded by intense seismic activity marking the mechanical response of the volcanic edifice to interior pressurisation. This seismicity is analysed to yield the temporal change in the seismic scaling exponent, D, inferred from the seismic b-value, that in-turn is related to the seismic moment of an earthquake. Time evolution of D pre...

We apply skeletonization approach to geophysical data to recognize geologic structures and pick seismic horizons automatically. We formulate the technique to be explicitly applicable to all gridded geophysical data. The method consists in extracting multiple features of “wavelets” which may be single or double peaks or troughs characterized by amplitudes, widths, orientation angles, spatial dim...

This dissertation addresses the problem of interpolating irregularly spaced seismic exploration data to regular spatial locations. This problem arises in practice in three-dimensional seismic exploration in such applications as Kirchhoff prestack migration, multiple elimination, waveequation migration, and 4-D seismic monitoring. I formulate data regularization as a linear-estimation problem an...

Exxon Neftegas Limited, as operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG) on behalf of the Sakhalin-1 consortium conducted a 3-D seismic survey of the Odoptu license area during 17 August-9 September 2001. A portion of the primary feeding area of the endangered western gray wha...