2D Multi-scale Cell Tomography for Near Surface Velocities

Traveltime tomography has become an effective means for solving statics problems. However, traditional single-scale tomography (SST) does not obtain the best velocity values for model cells with low ray hit counts, making smoothing or interpolation of the velocity field after inversion a common practice even though it often reduces the accuracy and resolution of the solution model. Multi-scale tomography (MST) can address the above drawback by simultaneously inverting for velocity components of many overlapping SST models with different cell sizes. The final MST model is a superposition of inverted solutions of all overlapping cells. Here the MST method is demonstrated using 2D field datasets from western China.