Adaptive Encrypted Ray Tracing Method

Abstract:

In the seismic beam migration methods, rays are traced from the starting point at equal sampling intervals of the emission angle. However, with the propagation of rays, it is difficult to ensure the ray coverage of the model. Here, we present an adaptive encrypted ray tracing method. As the rays traveling, new rays are automatically inserted according to the ray distribution. The essence of the method is to give appropriate judgment conditions for inserting new rays. The purpose of inserting new rays is different from that in the wavefront construction traveltime computation algorithm. In this method, inserting new rays is to ensure the ray coverage of the model. Therefore, we give two judgment conditions: 1. Whether the distance of adjacent rays on the same wavefront is greater than the threshold; 2. If the condition 1 is met, whether the ray coverage at the new ray insertion position is lower than the threshold. When both condition 1 and condition 2 are met, a new ray will be inserted. The threshold in condition 1 is a variable related to the ray propagation distance. The greater the propagation distance, the greater the threshold is. The threshold in condition 2 is obtained by the summation of the beam amplitude.