Technical Content

In ocean bottom acquisition, receiver side deghosting is normally done by summing together the hydrophone P and geophone Z data. A prerequisite for this method to work effectively is the precise calibration of geophones to hydrophones, so as to compensate for the differences in ...

Low frequency information is required for quantitative reservoir characterization. Because borehole measurements are often (laterally) sparse and preferential towards reservoir locations, there is much uncertainty on the low frequency models away from well control. Methods to improve the reliability of the low frequency data ...

Migration Velocity Analysis in the subsurface-domain measures velocity errors via (extended) image-domain residuals with respect to an ideal reference image and then updates the velocity model in order to minimize those residuals.Because of the similarity between images with similar extension parameter (shot number, offset ...

Analysis of time-lapse data is performed on migrated seismic images, which represent the spatial and time-lapse variability of the medium’s reflectivity. The process of migration effectively rotates the wavelet so that it is normal to the imaged reflectors. Processes used in 4D reservoir analysis ...

We discuss the problem of creating low frequency models for inversion and suggest a simple facies trend-based method which reduces reliance on prior laterally-varying assumptions about the heterogeneity of native reservoir properties. In our example, we were able to identify key hydrocarbon-bearing facies from ...

The May edition of Oilfield Technology is freely and widely distributed at the EAGE conference. CGG paid to appear on the cover and also got to contribute an article on a topic of our choice. This was designed to reflect our current advertising and ...

There are a number of geophysical challenges when attempting to image the sub-surface in the Central North Sea. These consist of shallow anomalies, heavy multiple contamination and sharp velocity contrasts. With a combination of broadband data and CGG’s latest processing and imaging techniques, these ...

The main area of hydrocarbon exploration in the Northern North Sea has been within pre- and syn-rift Jurassic sandstones. This is with the exception of chalk reservoirs in the Ekofisk field and Palaeogene sand reservoirs of the Frigg field. Now, with ignited interest in ...

We present a method to enhance the bandwidth of seismic data in the continuous wavelet transform (CWT) domain. By utilizing the features of CWT in detecting time-variant frequency content and automatically designing band-dependent time window, we can enhance the seismic bandwidth mostly based on ...