Scholarly record

OBTANING VELOCITY MODEL WITH KINEMATIC WAVEFIELD ATTRIBUTES BY TOMOGRAPHIC INVERSION

M. Soleimani, I. Piruz

Abstract

Making macro velocity model is the most important part in any seismic data processing system. It is a very time consuming and none accurate step in conventional methods like NMO/DMO/stack. In this article, we drive a velocity model for a synthetic data with new introduced tomographic inversion method. This method uses the kinematic wavefield attributes which would yield from common reflection surface (CRS) stacked data. These attributes are normal (N) wave and normal incidence point (NIP) wave curvatures. The tomographic inversion will be performed in three steps, automatic picking, 2D inversion and modeling. In automatic picking, a large amount of points on the reflection events will be picked which assumes to be placed on the subsurface reflectors. The automatic nature of picking will reduce the time of picking and improve the signal to noise ratio in final section. In the next step, the travel times for these points will be calculated by ray tracing technique. At the end, in final step, the travel times and rays will make the desired section of the macro velocity model. The other advantage that differentiate this method from others, is that we can easily test if the model is accurate or not and update is as fast as possible. In a true model, the events on data volume should be offset dependent which gained here. This section has a high S/N ratio with more accuracy than the section which derived from conventional methods.

Publication details

Back to publication list