Creation and Analysis of the Interval 3D Model with the Constrained Dix Inversion Method from the RMS Velocity

Abstract

Velocity models are needed in the process of making 3D earth models. The interval velocity model is more representative of the actual geological condition compared to the RMS (Root Mean Square) velocity model for the reason that at the interval velocity, the ray undergoes a ray bending that satisfies Snell's law, on the contrary at the RMS velocity when the ray crosses the two layers of different density then the ray is transmitted. The geological information shows that in the research area contained reef carbonate, causing a high lateral velocity variation due to the ray bending when passing through the layer boundaries. In this research, an interval velocity model analysis of the RMS velocity model was carried out using the constrained dix inversion method. The data used include seismic data in the form of CDP (Common Depth Point) gather and RMS velocity, and well data. The result shows that the interval velocity model has a better actual geological model compared to the RMS velocity model. This is indicated by the flat depth gathers, semblance which coincides with zero residual moveout axis, and the correlation between the depth image produced by the markers (well seismic tie).