Hampson russell inversion series#

Well logs are first conditioned and edited to ensure there is a suitable relationship between impedance logs and the desired properties. Inversion includes both seismic field data and well data, where well data serves to add the high frequency below the seismic band and to constrain the inversion. To ensure quality, the inversion result is convolved with the wavelet to produce synthetic seismic traces which are compared to the original seismic. Once the wavelet is identified, seismic inversion computes a synthetic log for every seismic trace. Errors in well tie can result in phase or frequency artifacts in the wavelet estimation. Accurate wavelet estimation requires the accurate tie of the impedance log to the seismic. Minor edits and 'stretch and squeeze' may be applied to the well to better align the events. When the estimated (constant) phase of the statistical wavelet is consistent with the final result, the wavelet estimation converges more quickly than when starting with a zero phase assumption. After the seismic wavelet is estimated, it is used to estimate seismic reflection coefficients in the seismic inversion. Wavelet amplitude and phase spectra are estimated statistically from either the seismic data alone or from a combination of seismic data and well control using wells with available sonic and density curves. The inferred shape of the seismic wavelet may strongly influence the seismic inversion results and, thus, subsequent assessments of the reservoir quality. Accurate wavelet estimation is critical to the success of any seismic inversion.

Hampson russell inversion series#

Typically, a reflection coefficient series from a well within the boundaries of the seismic survey is used to estimate the wavelet phase and frequency. Although the order presented reflects advances in inversion techniques over the past 20 years, each grouping still has valid uses in particular projects or as part of a larger workflow.ДЄll modern seismic inversion methods require seismic data and a wavelet estimated from the data. The combination of these categories yields four technical approaches to the inversion problem, and the selection of a specific technique depends on the desired objective and the characteristics of the subsurface rocks.

seismic resolution or well-log resolution.

These can be roughly grouped into two categories: There are many different techniques used in seismic inversion. Because of its efficiency and quality, most oil and gas companies now use seismic inversion to increase the resolution and reliability of the data and to improve estimation of rock properties including porosity and net pay. Seismic data may be inspected and interpreted on its own without inversion, but this does not provide the most detailed view of the subsurface and can be misleading under certain conditions. The amplitude and frequency of these waves can be estimated so that any side-lobe and tuning effects introduced by the wavelet may be removed. These surveys record sound waves which have traveled through the layers of rock and fluid in the earth.

Geophysicists routinely perform seismic surveys to gather information about the geology of an oil or gas field.

5 Pre-stack seismic resolution inversion.

4 Post-stack seismic resolution inversion.