3/29/2021 0 Comments Hampson Russell Cgg
By continuing to browse the site you are agreeing to our use of cookies.The predicted properties can be any log types available, such as porosity, velocity, density, gamma-ray, lithology and water saturation.Emerge can also be used to predict missing logs or parts of logs by using existing logs that are common to the available wells.
It then applies that transform to derive a volume of the log property from the seismic volume(s). It can predict missing logs or parts of logs not by using seismic data, but by using existing logs that are common to the wells in the training data set. Hampson Russell Cgg Software Download Credentials AndRequest software download credentials and assistance with setting up user IDpassword. For a given angle trace S ( ) we can therefore extend the zero offset (or angle) trace given in equation 11 by combining it with equation 1 to get. The first is that the linearized approximation for reflectivity holds. The second is that PP and PS reflectivity as a function of angle can be given by a set of linearized equations. The third is that the background trend can be described by a linear relationship between the logarithm of P-impedance and both S-impedance and density. Given these three assumptions, we show how a final estimate of P-impedance, S-impedance and density can be found by perturbing an initial low-frequency model. After a description of the algorithm, we then apply our method to both a synthetic and real data set. One solution to this problem was discussed by Russell et al. Recorder, which was based on the SEG expanded abstract by Hampson et al. Figure 1, taken from Russell et al. P-wave at the boundary between two elastic layers in the subsurface of the earth, with an incident angle equal to 1. Using the Zoeppritz equations, and a knowledge of the angle of incidence of the input P-wave as well as the velocities and densities of the two layers (noting that the other angles can be computed using the angle of incidence and the velocities using Snells law), we can easily perform forward modeling at the layer boundary to compute the amplitudes of the reflected and transmitted waves. This can also be generalized to multiple layers for both the primaries-only case and also the more complete case in which transmitted, converted and multiple reflections are taken into account (Fuchs and Mller, 1971, Kennett, 1983). However, the inverse problem of finding the velocities given the amplitudes is much more difficult than the forward problem, given the nonlinear nature of the Zoeppritz equations. For that reason, Hampson et al. Aki-Richards equation (Aki and Richards, 2002, Richards and Frasier, 1976) which was re-formulated algebraically by Fatti et al. Simmons and Backus (1996) also assumed that and V P are related by Gardners relationship (Gardner et al. Unlike Simmons and Backus (1996), their method is parameterized by the three terms, V P V P, V S V S, and, again using the Aki-Richards approximation. The authors also use the small reflectivity approximation to relate these parameter changes to the original parameter itself, or. Similar terms can be given for changes in both S -wave velocity and density. This logarithmic approximation allows Buland and Omre (2003) to invert for velocity and density, rather than reflectivity, as in the case of Simmons and Backus (1996). Hampson et al. (2005) inverted directly for the P and S -impedance terms and density, using a similar small reflectivity approximation to the one used by Buland and Omre (2003). They also used modified relationships similar to those of equations 5 and 6. Hampson Russell Cgg Full Theory OfIn the next section we will start by reviewing post stack inversion, then we will review the full theory of prestack PP simultaneous inversion, and then we will extend the method to PP and PS data. First, by combining equations 1 and 7, we can show that the small reflectivity approximation for the P-wave reflectivity is given by. ![]() Combining equations 9 and 10 gives us the forward model which relates the seismic trace to the logarithm of P-impedance. If equation 11 is inverted using a standard matrix inversion technique to give an estimate of L P from a knowledge of S and W, there are two problems. First, the matrix inversion is both costly and potentially unstable. More importantly, a matrix inversion will not recover the low frequency component of the impedance. ![]()
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