Analysis and understanding of seismic anisotropy has proven to be a valuable tool in many exploration and reservoir management studies. Seismic anisotropy should not be viewed as a problem that must be dealt with but instead regarded as an additional attribute to understand the rocks within the reservoir and overburden. Recent developments in borehole and seismic methods coupled with the latest...

conclusions pet/ct can provide diagnosis and more accurate staging, location of tumor with its capability in providing the anatomical and physiological information synchronizes. therefore pet/ct plays an important role in oncology. objectives in this paper, we evaluate application of pet/ct for improve oncologic imaging. methods the papers were searched in pubmed and scopus databases with the r...

The fidelity of depth seismic imaging depends on the accuracy of the velocity models used for wavefield reconstruction. Models can be decomposed in two components corresponding to large scale and small scale variations. In practice, the large scale velocity model component can be estimated with high accuracy using repeated migration/tomography cycles, but the small scale component cannot. When ...

An initial study is performed in which dynamically focused Gaussian beams are investigated for seismic imaging. Focused Gaussian beams away from the source and receiver plane allow the narrowest and planar portions of the beams to occur at the depth of a specific target structure. To match the seismic data, quadratic phase corrections are required for the local slant stacks of the surface data....

Wavefield extrapolation by spatially variable phase shift is currently a migration tool of importance. In this paper, we present a new prestack seismic migration algorithm using the Gabor transform with application to the Marmousi acoustic dataset. The imaging results show a very promising depth imaging algorithm, which is competitive with the best depth imaging algorithms. The Gabor depth imag...

The nature of failure in earthquakes is one of the most fundamental questions in geophysics. We approach this problem using near-source seismic recordings of strongground motion to image the rupture process of earthquakes. We apply the technique to three well-recorded earthquakes in California and interpret the results in terms of earthquake rupture dynamics. To calculate theoretical seismogram...

Benchmarks of our “production” codes show that Pentium-based multi-processors computers running the Linux operating system are attractive options for SEP’s next computational server(s). A four-processor SGI 1400 L (500 Mhz Pentium III Xeon) has consistently performed as well as, or better than, our SGI Origin 200 (180 Mhz R10000). We used the Portland Group’s pgf90 compiler to compile our bench...

A novel imaging process, referred to as vector image isochron (VII) migration, is specifically designed to reduce artifacts caused by arrays with limited apertures. By examining the assumptions behind generalized Radon transform (GRT) migration, a new approach is found which identifies and suppresses array artifacts, based on the array geometry and the migration earth model. The new method work...

Dynamic imaging provides an effective way to integrate previous time-lapse data with current data in order to estimate a current model. We present two methods useful for continuous dynamic reservoir and subsurface monitoring. The first method is a stochastic method for the inversion of geophysical data. It uses the ensemble Kalman filter (EnKF) that we demonstrate using time-lapse surface seism...