Checkerboard grids before and after B-spline sampling by Jive3D. The bottom plot shows the input checkerboard with dark colours indicating a negative anomaly, while lighter colours indicate a positive anomaly. The top plot shows the input checkerboard grid after Jive3D has sampled the input model. The colour scale is identical to the bottom plot, and the ±0.1 km s⁻¹ contour of the original input checkerboard in overlaid on top of the sampled checkerboard. The inset shows a zoomed in section of the plot, to better show the effect of Jive3D sampling on the input checkerboard. On all plots, the white lines represent the modelled interfaces taken from the synthetic model.